Ep. 86 - Decisions Made! - Let's Get Technical

[@dejanlupo]

Great video. Here is my amperage calculation. You must devide 360A with 3 phases and probably also devide by two because of two wires. So each wire is loaded with max 60A.

[@TheDigitalMermaid]

OOOOOOH, huh, why didn't I think of / realize this! OK, that makes a lot more sense why the wires are relatively smaller. Thank you!

[@mikeunum]

@@TheDigitalMermaid - We all have times where we can't the forest with all that trees You could use a gear system so you can switch between the big motor and a 5 kw motor. OK you need a second controller for it.

[@theradioweyr]

Thanks for this, came to say this and you beat me to it.

[@TheDigitalMermaid]

I could, but I'm really favouring simplicity as much as I can... A part that doesn't exist is a part that can't fail. :)

[@theradioweyr]

@@TheDigitalMermaid I was referring to the 3 phase power current requirements per lead but thanks for the reply. I just became a Patreon. You are much like me, I like to do all discrete design elements by myself, but sometimes I get stuck and say, you know what, that complicated relay protection assembly for illusory back emf protetection I have been trying to prototype for 3 weeks is better served by a $6 dollar board with a box of spares.

[@WiSeNhEiMeR-1369]

Thanks for explaining the REGEN concept SAIL POWER + propeller sending ELECTRICITY back to the 48 volt BATTERIES Thanks COOP ...

[@SimpleElectronics]

I'm excited about this new phase! Please reach out if there is anything I can help with - or if you get to a point where you want to air it out on a podcast! Keep it up!

[@TheDigitalMermaid]

Will do! As I mentioned in the video, and maybe even on the podcast; My long term goal is to help build an open source, hackable marine platform. So sharing all the code and designs is part of that, specifically because I know folks will improve it far better than I could ever do alone.

[@TheCreat]

I very much enjoy these theory-craft style of videos, even though I assume the greater public may not. Thanks for all the detail, as always. What I can offer in contribution later on: Like you, I have an an IT/coding background (C++ specifically). So once the code for the throttle-management-arduino is written, I can do a code review. Having more eyes on critical code/infrastructure like that surely won't hurt. I had forgotten to join the patreon discord, but fixed that now. So if/when you want eyes on something C++, just let me know.

[@TheDigitalMermaid]

See, this is why I love open source! I didn't mention it in the video, but one of the things I'm hoping to do longer term is to have a small community of folks working on / helping with an open platform for boating. One of the reasons I decided to go inboard was that I couldn't find a pod system (or really even inboard systems) that were truly hackable. If I can make this work, my dream is that it might kinda become a seed for an open marine platform (and who knows what else). So yes, code review would be more than appreciated! I'll setup a github repo when I finally get started.

[@HadrienDorfman]

​@@TheDigitalMermaid yeah well... if you really want to promote open-source, you may have to take a look at the vesc before using this kelly thing ^^ you would have everything you want and a basis for real open source, non proprietary protocol...etc (as well as less headache.. because kelly... you know.. hum :) )

[@TheDigitalMermaid]

Heh, well what's the old saying; "Don't let perfection be the enemy of 'good enough'.". I love open source, but I'm not a zealot also. For this project, it's striking a balance between hackable / repairable and time to get back on the water. Who knows though, down the road a controller swap might entirely be on the table.

[@asderven]

Thank you for making these videos. I dont watch them as often as i should. Simply because my focus is more on building batteries for now. But these technical videos teach me quite a bit, things to consider in a design phase.

[@TheDigitalMermaid]

I'm happy when folks watch at all, so thank you. I'm really happy you learned something from 'em!

[@Michael-AUS]

I love the 'overkill' and 'over-engineering' aspect of this build. Awesome!! Can't wait to see it.

[@TheDigitalMermaid]

^_^ - Thanks, Michael! Overkill is bestkill.

[@craneville5446]

Hey it's me from episode 79. Very happy to see you made it back safely. You have great detailed content and looking forward to your adventures.

[@TheDigitalMermaid]

Hiya Crane! Nice to see you around, and thanks! I'm happy when people appreciate the heavier technical content. :)

[@charles.neuman18]

14:35 "I haven't torn it apart yet" -- that's probably the most digimer thing you've said on your channel.

[@TheDigitalMermaid]

Well this comment was

[@planecrazy9208]

You are incredible! Your enthusiasm and capability is infectious. Good luck :)

[@TheDigitalMermaid]

To me, the greatest compliment is hearing that I helped encourage others to take on a task. So if my enthusiasm is infections, than I am really happy!

[@ArcticSeaCamel]

This approach with the different motors is very interesting! Looking forward to see how it comes in reality and what kind of performance you can get it with that and of course the regen. For my new boat, I’m planning to do double saildrive system with two 10 kW motors. But this video made me think that should I do something similar for them to get more efficiency and maybe more regen efficiency. One thing I have also been thinking used to really optimise everything from the propeller up especially for the regen! Propeller for that looks very different from propulsion one, but it should work for propulsion as well if needed. Keep it up!👍🏼

[@TheDigitalMermaid]

Thanks for watching! How long until you install your motors? If your channel is more or less up to date, I'm guessing not for the '24 season? If that's the case, I should hopefully have field-tests / real results before you buy. :)

[@ArcticSeaCamel]

@@TheDigitalMermaid Still several years to go for me!

[@TheDigitalMermaid]

After posting, I went back and watched some of your older videos. Really ambitious project! I'm very keen to see how you make progress with it. If you have a few years ahead of you still, well perhaps I'll be visiting Finland before you install your motors. :D

[@loucinci3922]

Enjoyed the video. Good info. Thanks for sharing

[@denislamadeleine1181]

I'm quite stoked for this project as well. Oddly enough I'm not interested in converting to electric at this time but I do find your project quite interesting. I can't wait to see progress and see the final numbers. Maybe you will convince me that this is the way to go when I get ready to buy a bigger boat and go cruising. Excellent lessons as always Madison, Cheers!

[@TheDigitalMermaid]

I'm very happy to hear that, Denis!

[@KeritechElectronics]

Hey, you look so awesome in the new sweater! :) Looks like more awesome stuff is coming. I'll be sticking around, sweetheart!

[@TheDigitalMermaid]

It was such a lovely early Christmas present! Of course, happy to have you around always. Coming content will be much more up your alley.

[@KeritechElectronics]

@@TheDigitalMermaid ha! Same here. My teeny tiny channel just turned two. I'll be doing some C64 stuff pretty soon, too :).

[@denisebrooks4513]

You are the best. We are going to be literally following in your footsteps with our Cape Dory 28.

[@TheDigitalMermaid]

This makes me very very happy to hear! Please share your conversion progress, I'd love to hear how it goes!

[@boomermatic6035]

I really like the idea of having two different Multiplus II's for worldwide power compatibility. I would drop a question in the Victron community forum to see if anyone has done that to hopefully avoid any gotchas.

[@loucinci3922]

Enjoyed the video. Thanks for sharing

[@TheDigitalMermaid]

I'm really happy to hear that, Lou!

[@johndeer2032]

I really enjoy your enthusiasm (and your orange sweater looked better 🙂 ). I'm currently also converting a sailboat to electric but using the small 3kW golden motor. The sailboat is also used for regatta's and the boat is a lot smaller than yours. However, I doubt that you can regenerate significant amount of power from your propeller. If you try to turn the motor shaft by hand you already feel how hard it goes and there is not enough "grip" between propeller and water. A gearbox/reduction would certainly help. Most of the time you will operate the engine in the lower efficiency ranges. The torque is needed when you accelerate but once the boat is moving at the speed you want, you can take the rpm's back to save energy (and not operate the engine at optimum efficiency).

[@TheDigitalMermaid]

A 17" prop is a lot of surface area to apply a rotation to. :) However, it's all speculation until she's back in the water.

[@charles.neuman18]

Wow, this phase is going to be fun. I sure liked the boaty parts, but now that I know you're going to do this the hard way (and why wouldn't you?), the technical parts will be quite interesting!

[@TheDigitalMermaid]

Thanks! I really hope it's fun and maybe helpful for fellow nerds who might want to do something like this, too.

[@alexpyattaev]

The idea with 2 motors of different sizes is amazing, great work!

[@TheDigitalMermaid]

I am really really excited to do both comparison testing, and parallel testing. It's going to be so much fun!

[@alexpyattaev]

Also, consider getting a proper, automotive grade microcontroller, arduino board will die when it smells saltwater. I would be happy to help with getting it going if you want.

[@TheDigitalMermaid]

@@alexpyattaev Andrew and I are planning, when the design is done, to make a custom PCB. If/when that happens, it'll be beefed up and tinned, conformally coated, etc.

[@alexpyattaev]

@@TheDigitalMermaid Sounds like you got the basics covered! Just make 3-4 of those boards =)

[@TheDigitalMermaid]

Absolutely, I'll have a generous spares kit.

[@tobiaslindblom2187]

you should fix the old one with an contrasting yarn and possible embroidery. Very modern.

[@TheDigitalMermaid]

Hahaha, I am many things, but modern isn't so much one of them... Well, says the lady making an electric boat... =/ :p

[@doug1olson]

(So I think you thought of this already, but I’ll leave the comment anyway. :) I have no experience doing what you are doing, but some questions come to mind. Maybe running a 5kw and a 10kw motor will let you pick the most efficient one for the speed you want. Also, I suspect that the regen efficiency curves are similar to the output efficiency curves so you may get better regen efficiency at low speed from the 5kw motor. Anyway, I appreciate your explanations and thought process. Good job!

[@TheDigitalMermaid]

The regen efficiency tracking the output efficiency is very much what I hope turns out to be true... If so, this should help scavenge power even at relatively lower speeds!

[@donburnett8629]

Ready for Phase 3

[@TheDigitalMermaid]

Same Don, same!

[@rickeemeee3252]

Yay keep figuring 😊

[@TheDigitalMermaid]

heh, in a way, "keep figuring" is kinda the motto of the project. :)

[@innerspaceavailable]

Loving the build out on the motors. So sorry about the insurance people. I swear they just look for reasons to get out of providing the coverage we all pay so dearly for.

[@TheDigitalMermaid]

These days, it's all run but software... If there isn't a check box saying "you can do this", they just say no. There's not a lot of room for a human to say "ok, this is fine", annoyingly.

[@tastiger91]

Gets more and more exciting as the journey goes.

[@TheDigitalMermaid]

^_^ - I know I'm getting more and more excited as time goes on!

[@CoolerQ]

If you've got a CAN bus on the controller, why not have your Arduino use that to drive the controller? That will probably be easier than dealing with analog signals in the presence of all the switching noise. Also, you showed the potentiometer you're planning to use as a throttle input. Cars often have multiple separate potentiometers for redundancy. You might want to look into modifying a car throttle pedal since they've already done the hard engineering.

[@ValRigoli]

Maddy I can't help but wonder when considering wasted energy, about the large inefficiency's of belt drives over a direct drive coupling, along with less need for, and stress on carrier bearings that will also require regular servicing etc. If using a second motor I'm sure they can be bought with double ended shafts so that two motors can be mounted direct coupled inline. Maddy you may have already considered all this, and I am certainly no authority on this, I'm just throwing it out there. The prop will be and interesting subject as well, I'm assuming that the propeller pitch for drive/propulsion will be vastly different than the pitch required for regen? Always love your videos and watching you figure things out.

[@TheDigitalMermaid]

Direct coupling would certainly be ideal, but it's just not feasible on my boat. The old engine uses a v-drive transmission, which you can see in the clip where I'm on the boat talking about the battery placement. So the best I can do is try to get the most efficient belt setup I can.

[@IstasPumaNevada]

This is very exciting. :) May your fun on this project far outweigh the headaches.

[@TheDigitalMermaid]

The thing about building stuff is that, no matter how frustrating it might be at times, when it works it makes all the hassles totally worth it!

[@larsltj]

I enjoy watching your videos! What a project! I'm an electric boat enthusiast myself, but with smaller dingies in fresh water during summer in Norway. I currently use a Golden motor X10 (6.5KW), and it has been running great since I got it a year ago. As this is a mobile setup, I decided to switch from Lifepo4 48V pack to a 14S NMC battery build to save some weight. I'm aware of the more aggressive chemistry, so everything is built sealed in a water tight box. My pack lost almost 10KG and I gained 70% more juice for longer runtime. Obviously no solution for a wooden sailboat, but if solid state batteries get mainstream, you can potentially get three times more dens than with Lifepo4.

[@TheDigitalMermaid]

In my mind, the real goal is for someone to understand the pros and cons of the available choices. If someone understands the concerns around NMC, and chooses it anyway, all good. I wouldn't do it, but then, I'm doing stuff others would never do. In the end, we're having fun as safely as each of us can. :)

[@tommussington8330]

We run parallel motors on our machines at work all the time we set them up to speed following but limit the torque to 80% (that can be tuned up or down to suit each application) on the slave. That way the slave has the correct speed reference to match the master motor rpm but it just go’s in to torque limit and sits there helping master along.

[@TheDigitalMermaid]

OK, so, I think I kinda understand what you're saying, but not completely. Can you recommend any articles or papers that explain this in more technical detail? I'd love to learn more about this.

[@tommussington8330]

@@TheDigitalMermaid we use AC motors and drives but principal is the same here is a Siemens white paper on parallel drives and motors for rolling industry but dont worry about what its driving. cache.industry.siemens.com/dl/files/055/14390055/att_870428/v2/FAQ-CD7F6930_MM4-multi_motor_en.pdf

[@tommussington8330]

@@TheDigitalMermaid this one you will have to translate but prinipals are the same with mater slave configuration giving slave torque limit. kzbin.info/www/bejne/lZ7Xc6qcmNeoY7s

[@jimduke5545]

@digimer sound familiar?

[@TheDigitalMermaid]

Brilliant, thank you!

[@fredflintstone1428]

Great video. I'm doing a similar thing with a power catamaran. I'm planning approx 45kwh per hull and 15kW electric outboards by an Austrian company called Aquamot, their Trend 15,0 motors. I will have a 6kW solar canopy and hopefully a weight of between 4 and 5 metric tonnes. The displacement should only be about 0.5m. Like you, all this is theoretical. Good luck with the insurance company.

[@TheDigitalMermaid]

Having two completely separate motors/props, and so much solar area is the only thing that makes me consider cats. I envy your capacity in this way. :D Please keep me posted on your project as you work on it, I love hearing about other's projects. :)

[@TKomoski]

Looks like some interesting thinkings coming up I will be watching 👍

[@TheDigitalMermaid]

Yay! ^_^

[@frejaresund3770]

I have been enjoyed, so thank you for delivering.

[@TheDigitalMermaid]

Thanks, Frej!

[@simonlewinson4170]

Suggest that you consider differential sizing of the motors. This still provides redundancy that you want but allows higher efficiency at “part throttle” as well as potentially greater regen. Having some type of clutch instead of a belt would also increase efficiency, but the ability to vary the drive ratio may give better end to end efficiency.

[@TheDigitalMermaid]

The prop is designed for 1200 rpm, and the motor is closer to 4000rpm, so I need to reduce the gearing via different sized pulleys.

[@simonlewinson4170]

@@TheDigitalMermaid What type of belt? Toothed belt may have less losses but vee or poly vee allow some slip to protect against over torque damage if prop stalls.

[@TheDigitalMermaid]

Originally I was leaning v for just that reason, but I am leaning back to toothed and will consider a sheer pin as a prop-strike safety.

[@silverleapers]

100Kwh at 48V! Mother of God!!! Please blow another T Class! Million views waiting to happen! 🤣Seriously though, great job on the efficiency curves and 5Kw and 10Kw multimotor scheme. Guessing the entire surface will be wallpapered in flexible thin sheet solar cells.

[@TheDigitalMermaid]

Hahaha! I am sure I'll screw up drastically, it's my habit, but I'm not gonna bring it on sooner. I darn neat shat my pantaloons last time! My goal is to get 1200~1500w of solar, but even that is admittedly "optimistic" on a canoe-stern sailboat like mine... Prop regen is what I'm really banking on.

[@KevIsOffGrid]

Electric canal boats here in the UK (Cruising the cut style) is around 2-3kw for cruising speed. but that's no tide or water flow, the absolute flat water. So those figures seem in the same ballpark.

[@TheDigitalMermaid]

Different hull shapes, too. Canal boats are flat bottomed and not the most efficient hydrodynamic shape. That said, I've loved seeing the episodes he's done on the electric canal boats. It's brilliant seeing more and more folks making the switch.

[@TK-123]

🎉🎉 Congratulations on reaching the next phase. I finally recognize that you were serious in doing this. What a great journey for you, and all us following along..!

[@TheDigitalMermaid]

Hehe, your comment is actually something I wonder a lot about... I often worry that folks don't think I'm serious, so in a way, this comment makes me quite happy. :)

[@frankthies221]

Madison, that’s a lot of KillyWatts! I love it. So basically your boat will have the same size of battery as the big Tesla Model S. 😁

[@TheDigitalMermaid]

Yes!!! How mad is that?! I ... wow. It's stupid. :D

[@DutchAussieProductions]

Wow, that is one complicated job. As always, your videos are great to watch. I am looking forward to seeing all your future ones.

[@TheDigitalMermaid]

Thanks, DAP! To be fair, I'm going a fair bit deeper than I need to, strictly speaking. I could just buy a kit, slap it in and be on my way, but honestly that sounds boarding. haha

[@ritchycamaro]

Hi Maddy, great to see you havent lost your spirit, after the sailing home adventure haha. Very interesting and challenging what your about to do. Great to see your enthousiasm. Nice sweater by the way!

[@TheDigitalMermaid]

The trip home removed any lingering doubt, to be honest. It was when I finally got to see the reality of extended travel and living on a boat, and I LOVED IT. Even with all the problems, my drive is redoubled after that trip. Thanks for the kind comment, and the sweater IS AWESOME!

[@georgelewis8904]

Thanks for your video, interesting look forward to future.

[@TheDigitalMermaid]

Thanks for watching, George!

[@spectrasymbol1062]

Love it! Don't hesitate with any questions about the SoftPot rotary membrane potentiometer. We like to assist with clarifications & support when we are able. :)

[@TheDigitalMermaid]

Well hello there, I have to say I wasn't expecting you fine folks to pop in! The next video, you're going to see your Softpot in the absolutely most questionable throttle setup ever. Haha! I'd LOVE to see a 180 degree version, as I'm leaving a lot of fidelity on the table using the 353 degree one. ^_^

[@mngbennett]

Love your channel. I had roughly the same sized diesel engine in a Gemini Catamaran but with a leg like an inboard/outboard. The leg is not made any more and the parts are getting hard to find so I swapped it out for an long leg outboard a few years ago. I have warned my wife that next time I would really like to go electric. Hopefully by then long legged affordable electric outboards will be available.

[@TheDigitalMermaid]

I think you're referring to "Sail drive" type motors, eh? I've seen plenty of electric sail drives, if so. Electric sailing is a young tech, but it's evolving FAST. By the time you need to look at a repower, the options should be a lot more that today.

[@mngbennett]

@TheDigitalMermaid The difference with a typical sail drive is for my boat the engine needs to be raiseable like an outboard or a inboard/outboard leg. The Gemini 105M can pull up its rudders and centreboards and get into 18" of water which lets us poke into places on the coast of BC that we couldn't in our previous boat a Catalina 30'. Torqeedo outboards were around when I repowered but way out of my price range but yes, prices have been dropping and more options are coming all the time. Thank you for all the information you provide during your learning experience.

[@TheDigitalMermaid]

@@mngbennett Aaaaah, I see now what you mean. Wow, 18", that's shallow!

[@mngbennett]

@@TheDigitalMermaid Other owners beach the Geminis but I think I would only do that in an emergency. I am looking forward to the your solar arch. That is on my list of to do's. I just built a light weight version using canopy parts and it is good enough for 4 100 watt panels but I want something sturdier that I can also use to lift the dinghy.

[@TheDigitalMermaid]

@@mngbennett The solar arch is something I've got a vague plan for but I'm not diving into in details yet. I'm waiting to see how to balance of the boat is after the batteries and motors are in, to get a feel for how miserly I need to be with the weight.

[@simonlewinson4170]

Just had another thought - if anchored in moving water you would be able to regen charge overnight too.

[@TheDigitalMermaid]

In theory yes, in practice no, probably not. You need a solid 4 knots or more to get any real power out of the system, from what I can gather.

[@dan2304]

To get good regen, a variable pitch prop is required to maximise the power produced. The equasion is half the area by density by velocity cubed. Water speed is critical.

[@TheDigitalMermaid]

Have you looked at how the Brunton Eco*star Autoprops work? The blades rotate 180 degrees

[@dan2304]

@@TheDigitalMermaid A/2 x d x V3 . The prop is important but double the area of the sweep and you get double the power production, double the water speed and you get 8 times the power production. The variable pitch just spins at an optimal rate to maximize generator efficiency at that boat speed. Most feathering props have adjustable pitch. With a displacement hull just adjust the reverse pitch to the most common hull speed to get suitable rotation speed for the generator. However that may be not the best pitch for reverse thrust. I admire your work but because boat speed is so critical for regeneration a faster hull design works much better also much more expensive.

[@NCislander]

Super excited for you. Love following your projects. Looking forward to the bench work as well.

[@TheDigitalMermaid]

Thanks, I'm really looking forward to getting stuck into this, too!

[@darrylruple4564]

Looking forward to all your future videos

[@TheDigitalMermaid]

Thanks, Darryl!

[@TheRonskiman]

That was a great video, and genuinely very interesting, the 42 minutes just disappeared. I find this project fascinating, it's also incredibly complicated. Can't wait to see how it progresses.

[@TheDigitalMermaid]

I worry often about the length of the videos, so hearing that the 42 minutes felt quick makes me really happy. ^_^

[@tomgraham6833]

Very interesting but I am an engineer so you know how that goes. Just wondering thatt you did not mentiion and data regarding Propeller performance data; you should get from the prop mfr curves of thrust vs RPM and efficiency. This will also lead you to think about about the match between your most efficient motor speeds and how well they math with the prop. Electronic devices are available that you can bolt in-line between the prop shaft and the motor or engine that will give a real time readout of torque and very expensive but perhaps the prop manufacturer has done some testing using such a device. FYI, they work on the principle of the amount off shaft twist as measured by a strain gauge. Does the boat have clearance for a larger prop? Merry Christmas

[@TheDigitalMermaid]

I mentioned that I'll be going into more detail on the propeller in a future video, as it's a huge topic. I linked in the description the propeller I am planning on, and I sent my measurements and other details, and they sent back a recommended size and optimal RPM. Using that will be what sets my pulley ratio (~3:1 ~4:1). The boat does have generous clearance, and that's why the recommended the 430mm (~17"), compared to the current ~13" prop I have on her now. I really want to have a way of measuring the real world output power, to calculate/display in real time the effective efficiency of the motor versus the input power. I'd LOVE to be able to "dial in" peak efficiency", also factoring in the boat's speed in water.

[@rtw8972]

Current ratings are for long runs of cable, not short runs. The manufacturer of the motor would have installed them in the motor. You need to place the controller next to the motor. Now, the cables that supply the controller must be much larger. I would recommend welding cable because it is very flexible, maybe 4/0. Test run your boat on your present prop and if necessary , calculate for another size prop. I would recommend getting the entire controller system from the manufacturer of the controller. Those anduino boards are not professional and will fail on the open sea.

[@TheDigitalMermaid]

Sort of, yes. I often use voltage drop calculators to figure the voltage drop over a given lenght/size of cable for a given run. I aim to stay under 2% drop, but if a run is tricky for some reason, I'll go up to 3% drop, but never more, and ideally much less.

[@TheDigitalMermaid]

On the prop; I need to get a new prop shaft to account for the new thrust bearings, and it'll have the taper and thread for the new prop. So comparing the 13" maxiprop to the 17" Ecostar is not really on the table I'm afraid. As for the arduino; I hinted at this in the video, but didn't go into detail; The atmega is to get started. The longer term plan is to move to a proper pic on a proper circuit board. The arduino is great for this early stage work.

[@segwaytothepicture1109]

This is all very interesting and I'm waiting to see how this all works out. Cheers to who set the sweater, it look great..

[@TheDigitalMermaid]

Thanks! And the sweater is AWESOME! Not orange, but my second favourite colour, forest green!

[@stevepettitt3520]

In the UK my boat is classed as a sailing vessel with auxiliary engine. I haven't asked the insurance broker but the type of engine (petrol/diesel/inboard/outboard/pedals) is unspecified. So if I changed mine, I wouldn't be informing anyone. I suspect you've been told something by someone who knows nothing, but is taking the safe line. (There are better descriptions for people like this.)

[@TheDigitalMermaid]

I run my own business, and have for over 20 years. It's made me very cautious about keeping everything above board, and in this case, I wanted them to know so that I wouldn't face a rejected claim if something happened. I know many projects just swap the motor and don't say anything, and I get it, but I'm too paranoid for that.

[@mikeunum]

Take a look at African Ironwood.Very hard and blackisch. Big pores and very stable.

[@TheDigitalMermaid]

I've seen ironwood, it's brilliant! I really want teak, if I can swallow the cost, as I'd love for it to match the existing teak toe rails on the boat.

[@eagleray1]

Thank you for all you hard work! I look forward to seeing you break some range records.

[@TheDigitalMermaid]

Thank you, and I love your optimism! ^_^

[@rtw8972]

Many devices made for sea use are specially treated with sealed circuit boards , one splash of sea water will kill them. All of your lcd displays for your should be sealed completely against sea air. There are industrial computers and keyboards made for industrial environments . I have used them in my designs and they are great.

[@TheDigitalMermaid]

Tinned copper and conformally coated circuit boards, yup. I plan to add a spray-on conformal coating to everything exposed when I am done.

[@ECOENERGI1]

Hi Digital Mermaid, very informative video as usual, Thanks. the resistive throttle you showed may not be ideal for use near water and humid environments, look into a hall effect controller or similar.

[@TheDigitalMermaid]

Aye, a few folks have concerns about the pot near water, it's something I'll put more thought into.

[@wimclinckspoor5731]

A hall sensor is the way to go, I’m using this type and it’s working for more then 4 year without any problem

[@johnxrv]

hi Maddy, had a small brian wave hit my skull. I this and an other video you talked about water cooling eletronic parts. Would it be an advantage to keep the cooling inside the hull, use the heat too warm up the cabin or watertanks, and all so have one less hole in the hull. And frome what i knowh, unless you are boating in the tropics, ships/boats get a ton of cooling from wind and water in contact with the hull, so maybe at bit of ekstra warmth might be nice.And you would get it from power you anyhow had to use too move the boat. Maybe it is at total no go brian wave, but now it has been shared , and you are free to use it or leav it to die . No hard fellings. :-)

[@TheDigitalMermaid]

So, I didn't talk about it in this video, but that is actually the plan now. I don't want to use sea water cooling anymore, too much of a hassle. So the current plan, and it's very vague as I can't yet know how much real cooling I'll need until I do sea trials, is to setup a couple air-sourced radiators, vented using the old engine bay vents that exhaust behind the helm. If that works, redirecting the flow to pull air in and exhaust the warmed air into the cabin in cold climates should be viable.

[@WiSeNhEiMeR-1369]

HOWdy Madie < WONDERFUL seeing YOU this Monday MORNING ... Thanks for POSTING COOP the WiSeNhEiMeR from Richmond, INDIANA ...

[@TheDigitalMermaid]

Howdy, Coop!

[@johnhayes3314]

Loved this episode

[@TheDigitalMermaid]

Yay, happy to hear that, John!

[@thomasdesloovere4200]

A couple of notes. 1. The variable resistor is not ideal due to sea water, it wil get corrosion and possibly get wrong readings, maybe look into hall effect sensors (or a hybrid of both). 2. Please don't only trust in one arduino, please make a redundant system (or a separate monitor system that cuts power in case of an abnormally) (same as traffic lights...) (preferable a other controller than you are using as main controller, so maybe a esp32 or a RPI) 3. For control handels look into a 3D printer with wood filament, you can sand it, treat it just like wood 4. (i don't know if you where planning to do this) but i don't ever cut power to the controller due to starting issues, communication issues... you apparently can as seen in the kelly datasheet but make sure that the contactors A. are rated for the currant and B. MAKE absolute sure that they can handel the big inductive and capacitive load when engaging the contactor and charging the caps in the controller 5. Thank you for using a good old belt system in stead of clutches (there are losses in clutches) 6. Please don't put the LiFePo4 batteries on there sides (it is technicality fine but still) (if it is specifically mentioned in the datasheet you could do it) 7. I didn't understand how you are planning to control the 5kw motor (2 controllers or 1) please use 2 separate controller because the controllers will learn how the motors react and will get very confused if you switch between the motors.

[@TheDigitalMermaid]

Ooooooh, detailed comment, I love it! Let me reply in kind. 1. From what I can tell (and I'll recheck the specs after this reply), it's tinned so corrosion should be minimal. That said, this is a very very good point I need to consider more deeply. 2. I was thinking of stealing a concept I've read about in space travel, where they have three devices (so three arduinos) receiving the data, so that if one disagrees, it's ignored. Obviously that level of fault tolerance is a "down the road" project, but given how critical throttle input is to safety... This said, there will be an emergency stop button at the helm (which is actually part of the new ABYC regs). 3. In my previous life, I was a (am a) hoobyist woodworker. The desk you see in the video is one I made (with the help of my teachers). So using wood is as much a chance to merge two hobbies in this project. That said, I can see how your idea would work great, and probably be easier/faster. For me though, I'm actually stoked to make the handle... Probably mock it up / refine it with something simple like pine, then build the final one in a nicer wood. 4. The LittleFuse contactor I chose (specs in the description) is rated for 400A, and are rated to withstand 1000v with a greater than 50mOhm resistance at 500v. 5. The losses in the clutch is almost equally important in why I didn't want to use them. I am trying to design this system for as efficient operation / longest range I possibly can get. 6. I'll double-check the specs, but I believe side-mounting the EVE LF280K is supported. My main concern originally was minimizing spill of one blew it's pressure vent, but given ABYC requirements, I'll likely be designing some sort of catchment in the battery boxes to handle this, regardless of orientation. 7. Two separate controllers. The goal, for redundancy, will be to have complete separation between the two, including separate cooling. Running in 10kw, 5kw or both will be managed in the arduino software.

[@tommussington8330]

I agree on this coming from an industrial enviorment with my experiance drives and plc programing inoure very wet paper plant. I'd use an 3 channel encoder ABZ and calculate the position via count up/count down register to give what speed you want output nd send that to the drive.

[@thomasdesloovere4200]

​@@TheDigitalMermaid thanks for your reply, 2. love to see that 3 is even beter (just keep in mind that i don't like to use 2 of the same for the reason if there is a manufacturing fault in one of them the other one wil also probably have that) 3. love to see that i have seen that you where in to woodworking (so am i sometimes if i have the time for that) but i am not so great at it that i can make a nice handel so i use the tools that exist to help me.. 4. I overlooked that in the description, my bad. They do look very nice just don't forget/misplace the flyback diode :) 6. I think indeed that it should not be a problem 7. perfect i just didn't catch it in the video (probably my bad)

[@thomasdesloovere4200]

@@tommussington8330 those are really nice but very expensive last time i checked, they are also a pain in the ass to program with arduino... (its possible that you can find a library that i don't know of...)

[@TheDigitalMermaid]

@@thomasdesloovere4200 Dude, after those little spark-fests, the role of diodes are kinda literally singed into my brain. haha

[@BobHannent]

Although you're going Arduino, you might want to use a Pi Pico as the hardware instead of an ST or Atmel based board. The Pico has hardware programmable IO (PIO) which can run tasks without the main code itself interfering. Which gives you the benefit of if your code crashes the outputs will be sustained until the code gets reset (e.g. watchdog). So I'd think that might be an option for improving safety.

[@TheDigitalMermaid]

Hrm, your point is valid, but I can't shake the worry of effectively running a full OS behind the helm controls. Let me ponder it more, it's possible I'll find the arduino too limiting in the end anyway...

[@BobHannent]

@@TheDigitalMermaid no, a Pi Pico is their microcontroller not the pi zero.

[@StikDragon]

that's a beastly motor! if you can get the controllers to go open-circuit on the output then you'll probably find there's effectively no power lost in spinning the motor, so you could likely just have both motors permanently connected via belts and simply select which one is active through software. the other one will free-spin. without a load on it the only energy needed to spin the shaft is to get it up to speed and then overcome friction in the bearings. try it - short all six of those wires together and spin it by hand, that's the difference between open circuit and a controller that's actively trying to get energy out of the motor as regen going to be interesting to see what regen is like on a boat, it never occurred to me that you could do it. are boat propellers efficient "in reverse" like this? in cars it works well since you have a solid mechanical connection to the road surface and they're always intentionally trying to shed energy because of braking. i wonder how it would compare to a small wind turbine, wind->power rather than wind->sail->water->power? looking forward to seeing more :)

[@TheDigitalMermaid]

I've had a few comments now suggesting that, if I can set it to freespin, the drag will be nominal. It'll certainly be something I experiment with! The prop I've chosen has a neat setup where the blades "flip over" 180 degrees, so they have a pitch designed for optimum forward motion, so when you go astern, they flip over, giving you optimal pitch for reverse. This means they're also the optimal pitch when doing regen. It's a brilliant setup! The link to the prop is in the description, and the company has videos showing how it works. If you lock the prop shaft, the blades with feather to minimize drag.

[@zazzysubstitution]

I think you can couple the 2 Motors to Prop Shaft using electric device, such as an A/C Clutch, so that you can swith between them on the fly. Just my 2 cents..

[@zazzysubstitution]

Or even a one-way clutch. Power will flow from either operating motor, or both, if you choose to.

[@TheDigitalMermaid]

I'm certain I could, but I worry about adding more parts... A part that doesn't exist can't break. I suspect that I'll find that I'll run on the 5kw 90% of the time, and only switch to the 10kw rarely. If that's true, swapping a belt won't be a big deal. If I find myself swapping more often, then I'll revisit clutches.

[@marc4322]

Great video! Your number on consumption look promising! Can't wait to see more

[@TheDigitalMermaid]

They're much more optimistic than what I thought, back in the beginning. It's driving me crazy now, I want to get in the water and see if these are realistic or not!

[@mwolrich]

Is the plan to regen under wind power? that sounds like a decent plan, it may only slow you down a small bit.. interesting idea.

[@TheDigitalMermaid]

Wind in the sails, prop in the water regen, yup. It's how I plan to get most of my power... Less than solar at full sun, but it'll work day and night, so long as the sails are up and there's enough wind. I will lose speed in water, but this setup allows me to lock the prop shaft and the prop will feather if I really want the speed more than the power.

[@akiraanderssonse]

I'm super excited about your journey to an electric motor. I'm going to buy a Golden Motor 5Kw with Kelly controller myself. Have completely different setup, but still very nice not to be alone in figuring out how it will work together 🤗

[@TheDigitalMermaid]

Oh that's awesome! Well as I learn, I'll be sharing everything, so hopefully I'll be able to help out that way. ^_^

[@MarkRose1337]

That sounds interesting. Gave you channel a sub :)

[@davidwright6950]

Have you spoken to SV Uma, they have so much data and experience for the last 5 years with a boat similar size to yours, they are on their 3 rd version. Also just to note rivers and canals in Europe mostly don’t have shore power for leisure craft

[@TheDigitalMermaid]

I follow them, but I have not spoken to them. I assume they must get a constant stream of emails / requests, and my channel is still really really small compared to them. So I do hope one day to chat with them, but I think I'll wait until I've grown the channel and/or gotten further along in the project. I don't want to bug them (or anyone else, really). Are there marinas where I could pay to recharge along the rivers over there? Well, I do plan to have a diesel generator for emergencies, but oh I'll be doing everything I can to avoid using it...

[@davidwright6950]

@@TheDigitalMermaid not really accessible for sail boats, around Netherlands you have more chance especially along mast up routes, coastal marinas are set up as that’s what we all use. SV UMA had a lot of motor data a few years ago including regen data. The lack of shore power on inland rivers etc is what is stopping canal boats etc with would otherwise be ideal and this is unlikely to change as no river side or canal side infrastructure to do this. Also over here you need to de rate your solar by about 50% for daily average and late in year you will have basically none, we have 300 watts and have had basically nothing for the last 6 weeks

[@TheDigitalMermaid]

@@davidwright6950 Solar in the winters here is also basically useless. I know that my 1.5 meter keel is going to block me from some rivers/canals, and I suppose when that happens, I'll just have to find some boaty folks interested in taking on a nerdly visitor for a trip around the local canals. ^_^

[@davidwright6950]

@@TheDigitalMermaid you would not think it but 1.5m is an issue on most of the European inland nowadays, we planned to go down the French system to the med but we hearing that this is now not easily and we are lifting keel and draw 900mm with it up, the issue is that it’s mostly ok in the middle but you cannot get to the bank, UK canals can take quite some time to progress as locks really slow you down, you can easily get hire boats to have the experience though.

[@TheDigitalMermaid]

@@davidwright6950 Aye... I'm coming to realize how the keel will limit me. Well then, so it is. It will be an excuse to try to make new friends who can take me on their canal boats, perhaps in exchange for taking them on some open water sails. :)

[@unixb4coffee]

Arduinos are just the ticket for DC motor control, there are already many, many PWM (for example) controllers and videos about to use them. Also a good plan to save the Pis for the asynchronous and scalable parts, like data collection and various networking connections to manage the data, but again the arduino is well suited to sampling inputs like throttle and then sending those to a data collection server lika a RPi. This looks very cool!

[@Ivansgarage]

That is a AC motor... motor speed is controlled by frequency. AC motor... DC motors are controlled by voltage...

[@TheDigitalMermaid]

In my case, the arduino won't control the motor directly, but control the signals going to the Kelly controller. For this, I think it's going to work brilliantly though. :)

[@MaxPivovarov]

You need programming MPPT controls for recuperative charging. So as i know this motor controller has only recuperative braking without control efficient point of recuperation.

[@TheDigitalMermaid]

This is something I still need to dig into, but I am pretty sure it has a selector for how aggressive the regen is. If so, one of the many benefits of the arduino is that I can program it to auto-adjust the regen aggressiveness based on the current speed in water.

[@tcloud24]

i'm still watching. it's a long tunnel, but i think i see a weak light at the end. you are making progress!! you may have said some where in the past but i'll ask here. what prop is on the boat now? from what you described as your method of operation, having/buying a feathering/folding prop won't allow you to charge while sailing. i did go to the website for the prop you are looking at and it says it can be used for that charging. it must be a magic prop. (lol) i also noticed they don't start giving numbers for charging until the boat speed is at least 5 knots. maybe that is when the magic begins. my first prop (3 blades fixed, 16 x12 cupped) would not start turning under sail until i reached 4 knots. i have changed things since then and have not done enough sailing to notice (smooth & quiet now) if it still takes that much speed or not. the old prop guy in San Diego said the more diameter with less pitch gives best results. their math came up with a "28" number for my prop. diameter plus pitch. he said for a displacement boat (not planing), don't go over square (pitch & diameter the same or pitch larger than diameter. for me, the limit would be 14 x14). i'm not saying don't buy that prop, but do study it well! it is a big investment and will be a major part of your overall plan. would be a shame if it did not live up to the hip. btw, a free-wheeling prop is not nearly the drag of a locked prop.

[@TheDigitalMermaid]

The current prop is a maxprop 3-blade feathering 13". It's a great prop in great condition, and I'm hoping to sell it when the time comes to help fund the project. The new prop is a different kind of feathering prop (linked in the description, and follow to their youtube channel to see videos of how it works). In short, the blades flip over 180 degrees, so they can design the pitch for optimal forward efficiency. When you want to go astern, the blades flip over, so now they have the optimal pitch for astern motion. This is the orientation they take for regen, also, meaning you can get optimal regen from them. if you want to feather instead, lock the prop shaft and they go into the 90 degree feathered position. The main concern for me, is the noise and vibration. I was spoiled that my boat came with the maxiprop... I didn't realize that until I was sailing on a boat with a fixed blade prop, and I suddenly noticed a vibration in the cockpit and a weird noise. I asked the captain what it was, and he looked at me weird and said "that's the prop free spinning". After that, I was like oooookay, I never want a fixed blade prop! I was stoked to find the Ecostar given it can feather and do regen!

[@tcloud24]

@@TheDigitalMermaid how does that saying go? "never say never, right? why do you think being a fixed bladed prop would be any worse than any other prop? have you ever had a tire out of balance? if so, you know it is not a nice ride, at least at some speeds. but because of that you won't quit using rubber tires will you? so, remember my comment about "smooth & quiet"? well, same fixed prop. it is just no longer hooked directly to the engine. i have a pillow block arrangement now that takes the thrust and are smooth as silk. plus no shaft alignment problems any more. from there a couple of u-joints and short shaft go to trans. engine is on soft mounts. different ball game. your drive will be very similar to that. since you are planning to belt drive the shaft, the shaft will have to have a bearing on the end to take the thrust and support the shaft. using a bearing like this... catalog.amibearings.com/item/spherical-o-d-accu-loc-bearing-insert/centric-collar-locking-bearing-insert-ue200-series/ue205-16 the shaft will be centered perfectly. use the style pillow block of your choice. i use a couple of shaft collars (one on each side of the bearing on the shaft) to insure the shaft stays in place. be careful where you buy. some stores think they are made of gold. here is one priced right that i used... thebigbearingstore.com/1-concentric-locking-flange-bearing-uef205-16/ so you reverse the motor, blades perform for going backwards, then stay that way unless you stop the shaft from turning? how cool is that?

[@PabloTBrave]

Was going to say have two motors and controllers for smaller wires fuses and resilience before you mentioned it @ 16:30. If you don't need the 10kw having a full redundant motor in master slave configuration could be overkill maybe 2 x 5kw motors both in operation for normal operation and obviously if one fails you'll still have movement but only 5kw total

[@TheDigitalMermaid]

By the time I realized the benefit of 5kw, I already had the 10kw in hand. hehe

[@MarkRose1337]

@@TheDigitalMermaid You'll be glad to have the 10 kw + 5 kw when fighting currents! An extra knot could make a big difference when needed

[@TheDigitalMermaid]

@@MarkRose1337 I think about the currents I hit on the Niagara river and I wonder, "what if Black Rock locks hadn't been there?". So ya, if I can parallel them, I am certain that, though rare, the times I need it I will be very glad to have it.

[@kevinnemrava]

Regrading regen. I would advise you be a bit pessimistic on how much you are going to get from it. I am still saying you SHOULD do it, it is worth it, just don't over estimate how much you will get from it. Ever time I have ever heard numbers quoted - it has been at travel speeds higher then you would expect and also with props bigger then you expect - I suspect that it is mostly releated ot area of the "prop circle" and that how pi*r^square for the area thing means even a bit bigger prop catches WAY more water.

[@TheDigitalMermaid]

Oh, I fully expect to be underwhelmed, but I am trying to be as effective/efficient as I can be. That said, one of the many reasons I bought the Landfall is her cruiser/racer lineage. She's shown me how easily she car get up over 6 knots in even modest winds. You're right, going from ~13" to ~17" prop is going to be a lot more drag, but then, if I need power, I'll trade speed for kw. :)

[@redrockroger]

If nothing can reweave, consider elbow patches of deerskin or chamois.

[@TheDigitalMermaid]

Aye, that's my fall-back, a couple leather elbow patches. My neighbour (who I am hiring to redo the cushions) is a wiz at this stuff, so I'm going to ask her to take a look at the sweater, also.

[@GabrieleBertaina]

Don't forget to add the charging/discharge losses to the equation.

[@TheDigitalMermaid]

Absolutely, though it was a bit beyond scope for this video.

[@irfanarefin1265]

ok this is something new. For an engineer working on E mobility sector based startups, specially working with 48 or 60 volts based systems only here as well as retro fitting, this whole project will be pretty much exciting see. EVs running on Seas, boy oh boy isn't that exciting to see.

[@TheDigitalMermaid]

RIGHT?! I am sooooo excited for this build! I love hearing about the projects others are working on, too. We're at a heck of a cross-roads in propulsion across the board, I strongly believe.

[@irfanarefin1265]

@@TheDigitalMermaid haha Yeah for sure.. Like your fascination with an arduino, I have the same fascination with an ESP32 btw haha. We built some prototypes of adaptive chargers that works with an esp....! bms, rapid chargers are next lol. Might shift to STM or Pi later when we go industrial more. Whatever, That got me even more excited really. Really would love to know about your updates within the phases , best wishes for that!

[@TheDigitalMermaid]

@@irfanarefin1265 Andrew uses ESP32s, but I think he put me onto the arduino as it's more accessible for my skill level. :)

[@irfanarefin1265]

@@TheDigitalMermaid interesting thing is esp32s and arduino boards have so much thing in common haha ... excited to see the integration as i'm seeing and learning a lot of new things as well. :D

[@TheDigitalMermaid]

@@irfanarefin1265 It's entirely possible that when I get the prototype done and we start looking at a custom circuit board, we'll switch to some sort of ESP.

[@clivestainlesssteelwomble7665]

Take a look at the system they use on windelo cats and the experiences of the rigging doctor also DIY.

[@TheDigitalMermaid]

I follow the Rigging Doctor and Uma, both are good channels, but light on technical detail (well, light by my somewhat rediculous standards ;) ).

[@clivestainlesssteelwomble7665]

Theres a young English guy mark from Wilding Sailing hes in Holland trying to complete a 42ft wharram pahi Catermeran .. Now originally the design would have used a single larger outboard or two high torque 9hps. I keep trying to pursuade him to do his own electric hybrid conversion. Using motors like yours ...it would simplify his propulsion needs considerably plus the Dutch along with many others are looking at banning diesel propusion from all inland waters conservation areas and some harbours. Theres a UK company Advaced electrical Machines producing modular motors that use no perminant rare earth magnets or copper .. that might interest you theres also a German Co called Molabo who produced a low voltage version with magnetic field gearing but they are prohibitively expensive. Battrey prices are dropping currently and Northvolt has produced a Na ion cell with the capacity of per kg equivalent close to Li phosphate.

[@TheDigitalMermaid]

I watch him, actually! I quite like his down-to-earth style. The thing with electric is that I would _never_ push someone towards it, because the way you think about powered propulsion really does change. I really came to understand this when I switched to an EV for my car; There are amazing pros, but also real cons. I think going electric is something someone has to want to do, in order for them to be happy with the new trade-offs. I just looked at AEM's website, and they seem pretty light on technical specs... Ya, battery prices are coming down a lot. It's awesome, will make all this accessible to more and more people!

[@dc1544]

Also look at pulley conversions. This could make 1kw of power act like 1.5kw of power for spinning the prop shaft.

[@TheDigitalMermaid]

How so? I'm already planning a ~3:1 or 4:1 reduction to get the motor speed down to the optimal prop speed.

[@dc1544]

@@TheDigitalMermaid A little research goes a long way for pullies. having your electric motor shaft spinning 1 time and the prop shaft spinning 1.5-2 times. Even higher maybe. Since Electric has so much torque its easy enough to do this. For regen you wan the opposite maybe even 4 to 1. this would mean 2 different pully systems. see regen can be increased by spinning the motor faster. maybe even a 10 to 1 pully for that.

[@TheDigitalMermaid]

@@dc1544 Aaaah, I get what you're saying now, ok. Hrm, that's an interesting idea... And ya, I have a LOT of homework still to do on pulleys. And on dozens of other topics. Haha! That's what makes this project so fun. I just need more hours!

[@dc1544]

@@TheDigitalMermaid or just clone yourself a couple times. put them to work lmao.

[@clivestainlesssteelwomble7665]

Get the sweater fixed ..and elbows patched. I have a couple of Arrans all round the British isles fishermens wives and fishermen would sit knitting local styles of jumper and each familly and community had its own patterns. The wool would be oiled with lanolin oil to keep water at bay and generate added warmth. It works . The knit needs to be tight to keep wind and water out and warmth in. The one historic downer, is one of the reasons for the unique patterns, if a fisherman went overboard and the body was found it would allow them to haul it out of the water and identify it. Another fact is a common name for a jumper in the UK is a Jersey... Jersey and Gurnsey are channel islands and known for their own styles of fishermens jumpers... In Scotland and the NE jumpers are called Gansey's .

[@clivestainlesssteelwomble7665]

I almost forgot look up a bunch of Canadian logging truck guys and their Electric Hybrid the Edison Topsey .. more power more torque less wt and when using the generator its up to 50% more fuel efficient and cleaner burning...less maintainance and back up.

[@TheDigitalMermaid]

I had heard the story about the sweaters being unique to help ID bodies, really drives home the risk fisherfolk used to face. I absolutley love good sweaters, and I want to keep them for a long time. My neighbour already fixed the orange sweater once, so I'll be asking her if she can help me again. :)

[@clivestainlesssteelwomble7665]

@@TheDigitalMermaid Spent my younger days studying down in the West country near to where Daz cats and Wharrams are from ..when we were not on the coast we would be doing field work on the Moors. Oiled wool sweaters Were standard kit. The Royal Navy were incredibly disgruntled when they were told they would have to give up their traditional white oiled wool roll neck sweaters.... They kept wearing them i dont think anyone dared rock that particular boat. 😂🧙‍♂️

[@TheDigitalMermaid]

@@clivestainlesssteelwomble7665 I've not learned much about oiling sweaters, but I very much expect to learn all about it. I love 'em, and expect to be wearing decent ones for many many years out of the water. :)

[@clivestainlesssteelwomble7665]

@@TheDigitalMermaid Lol 👍🏼🤞🏼 yup The other key to hybrids is simpler smaller gen motors kzbin.info/www/bejne/hJnapaRjlpJ4jqssi=_QhEZixQwuQSECn1

[@upnorthandpersonal]

Any reason in particular to go analog with the throttle control instead of using a digital rotary encoder?

[@TheDigitalMermaid]

Hrm, you're the second person to ask this, and the honest answer is "I didn't really think about it". I kind of defaulted to an analogue input, given the near infinite values I can get from it. When I next talk to Andrew, I'll ask him about a digital encoder option.

[@upnorthandpersonal]

@@TheDigitalMermaid Theoretically you can have infinite numbers, but your ADC is the limit here. A 10 bit ADC will give you 1024 values - you can easily get the equivalent digital encoder for this many positions.

[@TheDigitalMermaid]

@@upnorthandpersonal Aye, the DAC is a limiter, regardless, this is true.

[@ArcticSeaCamel]

We actually designed a simple wireless controller for my electric boat. It comes around to 3 buttons. First one used to put throttle higher, middle one is to stop and third one is to go reverse. If forward or reverse is pushed down, it will give a full throttle burst. We did initial testing this fall, hoping to get that system installed next summer for actual testing. Quite easy to do with ready to go Bluetooth microcontroller dodads. So far I’ve been using simple potentiometer, but probably gonna ditch that and do this button system for the fixed install as well.

[@TheDigitalMermaid]

@@ArcticSeaCamel I hinted about computer control of the boat, and for that, I was imagining from a tablet or phone, so wireless effectively. That said, I want to always have a hard-wired set of controls at the help that overrides any other signals. I'm old enough to never trust tech that much, particularly wireless tech. :)

[@dc1544]

I would bring a 2-3kw small generator that uses pump gas. a Honda or a generic depending on budget. That would give you with with 10 gallons around 40kw of charging. That would be your backup to backup.

[@TheDigitalMermaid]

The current plan is, before I start travelling, to try to rig up a single cylinder 8~12hp air-cooled diesel to a 60~100A 48v-native alternator, something like the Balmar 60 or 100. Diesel gives you almost 2x the kw per liter of fuel, and I'll have diesel anyway for the hydronic heater and stove.

[@Full-of-Starships]

​@@TheDigitalMermaidCould you use the diesel engine to power your 10kW motor in regen mode?

[@TheDigitalMermaid]

So, a) love your nickname! b) in the very early days of the project, I gave that a very real consideration. Also, considered installing a smaller generator where the engine is/was also. In the end though, I decided I'd rather the space for even more batteries. Go all in!

[@Full-of-Starships]

@@TheDigitalMermaid a) thanks! b), yeah, I meant the 8-12hp you mentioned. Can't wait to see you rip out that big old diesel.

[@AmyMrsR]

"well, you wont think twice, you'll be dead very quickly, but I digress" but what the heck? what issue does the insurance company have with the conversion?? Just the unknown?? and btw, love the music :)

[@TheDigitalMermaid]

Just the unknown, is the best I can guess. They didn't ask any questions, just a flat "No". So I assume it's a policy concern.

[@randycain5764]

Madison, 96VDC components like motor controllers, chargers and solar charge controllers, and inverters are isolated (designed to be ungrounded on both leads) such that they work with bipolar batteries. That is, +48v and -48v with a third lead coming from the mid-point of the battery as the safety and reference ground (0v). That center wire gets connected as the safety ground such that the voltage potential to ground is only 48v but the powered devices see the 96v potential.

[@TheDigitalMermaid]

Huh, so you could use a controller like that with a pair of 48v batteries? Wouldn't the two 48v batteries need to be isolated with their own controllers? I vaguely considered this back in the day, though series'ing two 48s to get actual 96v. What you're describing is fascinating.

[@randycain5764]

You're running 16S batteries, right? That's really just two 8S batteries in series. That midpoint busbar is the halfway point voltage-wise. Reference that halfway point to ground and you've got a bipolar battery, +24 and -24. The same thing works with 32S batteries: really just two 16S in series. BTW, I'm putting four bipolar batteries at +48/-48 into my 100% solar only catamaran conversion. Mine are 34S rather than 32S so it's 122kWh of storage and 9.84kW of solar.

[@TheDigitalMermaid]

@@randycain5764 The part that I'm confused about is that, with my current design, all six/seven batteries go to a common + and - bus bar, given the inverter and charger are 48v. So in a sense, it's kind of like a 16s7p battery, so where would I pick up the midpoint?

[@randycain5764]

@@TheDigitalMermaid I'm not suggesting that you should change your setup since you've invested in 48v bms, chargers, etc. In fact, your Victron systems won't support 96v. But, by way of example, six 48v could be turned into three 96v batteries by connecting the three 48v pairs in series. So, there would only be three negative battery leads and three positive battery leads connected to their respective +48 and -48 busbars. In each series-connected pair, the connection point between the two batteries is the 0v ground reference point and is connected to the ground busbar. Note that there are now 3 busbars! This is similar to the way split-phase 240VAC is done with two "hot" leads and one "neutral" lead, except that with the battery we don't normally pass current through the safety ground.

[@TheDigitalMermaid]

@@randycain5764 Oh, I didn't think you were suggesting I change, the die is cast for that already. Just the same though, I always want to learn more. Having three busbars is kinda how I thought it might work. Well in any case, it still ends up running foul of ABYC standards, so it's a fun thought experiment only, for me.

[@Joe.Blackwood]

Please watch Kris harbour with his water wheel. He bought a similar motor with major issues with suppliers over rating the max output. That could be just 1500w in reality

[@TheDigitalMermaid]

Found the videos, will watch in a bit, thanks!

[@bloodcarver913]

You are not considering drag in water and wind resistance if head on. Real conditions will be different from a pre-calculated solution. I think you need to install some stuff and go out and test it and then make changes.

[@TheDigitalMermaid]

Did I not mention a few times "flat calm" as a qualifier to these numbers? I spoke about wanting to have the 10kw, and possibly even paralleling with the 5kw for 15kw, specifically to overcome strong real world conditions, like headwinds and currents. I also talked about exactly needing to get on the water to start putting this theory to the test...

[@dc1544]

Talk with Sailing UMA. They converted years ago and I bet they know which insurance companies to go with.

[@TheDigitalMermaid]

I'd love to chat with them someday, but at this point, I suspect my channel is too small, and they probably get an endless stream of emails and requests. So, someday, but I worry I'd just be annoying if I reached out now. :)

[@dc1544]

@@TheDigitalMermaid I am sure they don't care how big or small your channel is. Hit them up, I bet they would love to let you pick there brains.

[@nigelcharles511]

Efficiency for regen might not be too great. I looked at using aircraft props as wind generators but the twist of the prop is optimised for thrust not power extraction. Might not be quite as critical with hydrodynamics but it is totally useless for aerodynamics. Unless you have a lot of deck space for panels I would only assume that panels will look after the ancillaries.

[@TheDigitalMermaid]

One of the reasons I chose the prop I did (link in the description if you want to see more technical details) is that their blades flip over 180 degrees. So they've been able to design them for optimal efficiency in one direction, unlike most other props. They don't care about efficiency in reverse because the blades just flip over. I'm really hoping that's going the help with the regen, but it's all theory until I get in the water.

[@dadzilla007]

The insurance was the last thing I'd thought would be a problem for you. Did they state the exact objection to the electric drive?

[@TheDigitalMermaid]

Nope, no opportunity to discuss, simply a flat "no".

[@edwardvanhazendonk]

Hi Maddy, thanks for sharing your thoughts, I've got a couple of questions, maybe a heads-up. I saw a resistive with ball bearing setup for your input throttle: please be aware that you are in a saline environment, it will oxidate faster than you think, essentially killing your possibility to drive the engine, try to find either a capacative or optical way of doing this as it would last a lot longer and is sturdier (alike the resistive vs capacitive plant sensors), this is just my fear when running such parts. Also you conversed HP to KW. The Diesel KW is maybe 40% effective, so a large 100KW motor hasn't got 40KW of output, so maybe your peak isn't that import but more the turning speed of the propellor, the diesel engine running at a certain RPM drives the shaft at a certain RPM, that might be important as a electric engine might run different speed and that conversion is important for the "driveability" of the propellor. And finally, when you want to regenerate from a propellor, it's shape will be important, because they might be having different "drags" in water, so a high power conversion propellor might slow down your boat when it is still. So maybe think of two propellors or generators on the side of the boat which are facing forward to charge the batteries. (But the last one might be a little lame when running on engine power). Probably you might need a conversionbox for the speed of the propellor shaft vs the speed of the electric engine. Just my thoughts, I'm no mechanical engineer, but let them please advice you on how to make this marine grade ready.

[@TheDigitalMermaid]

You're already the second comment to warn about the pot corroding, so I will certainly pay attention to that. I'll have spares, of course, but I might see about conformally coating all metal bits for extra protection. There will be an e-stop button at the helm (ABYC requires this), so in a pickle, that'll be the safety. The prop size and speed is hugely influential in efficiency, as I understand it, and it's partly why I'm investing so much in the prop I've chosen. This prop also flips over 180 degrees, so it has optimal pitch in forward, and in reverse/regen.

[@edwardvanhazendonk]

@@TheDigitalMermaid The good part is speaking freely on your planning, this will give you people reacting on your choices, either positive or negative and gives you to think about options. One of the parts of marine stuff it's mostly very expensive but for the reasons of running into storms and water goes everywhere then and salty water is evil 🤔. So I'm glad you look into the reactions and make your planning better. Just also to give you a heads-up, I think you follow Andy's channel, but he made a breakthrough with JK, the new BMSes might help your Victron setup to work better. And looking at what you plan to do, maybe try to have two seperate setups in your vessel, 3 banks primary power, 3 banks switchover power and 1 bank as general or backup power. This will give you options when you hit the ground running. With 2 MP's and 2 different solar inputs this might save you from harm (you can think of joining things or switching things). Just my thoughts not to critique you. Have fun planning and getting things to work, love to follow the proces.

[@TheDigitalMermaid]

@@edwardvanhazendonk A huge reason I wanted to start this channel is for the feedback. Taking in advice and experience from others is so important to giving this project the best chance of succeeding. I'm a few episodes behind on Andy's channel, but I am hoping to get caught back up asap. I know there's been a lot of JK developments. On the solar, the goal will be to have at least two MPPTs, one for port and one for stbd. Everything important will be redundant, for sure.

[@MarkRose1337]

@@TheDigitalMermaid The quick summary: JK fixed all his major complaints and the BMSes function exactly how he'd like them to.

[@TheDigitalMermaid]

Excellent!

[@somebody1869]

When it comes time to travel, come down the Saint Lawrence and through Montreal. Instead of the Erie Canal, do the Chambly canal to lake Champlain and then the Hudson. Or, go outside, past Percé and Newfoundland. In either case, you’re more than welcome at the Royal Saint Lawrence Yacht Club, where my little electric Beneteau First 30 lives.

[@TheDigitalMermaid]

I would LOVE to run out the St. Lawrence, and for a good while, that was actually my plan. I wanted to head to Nuuk, then Iceland, then Svaldbard and then down to winter in Denmark. However, I've been wisely talked out of it as my first big trip, given how challenging the north atlantic can be. That said, when I am in the water doing sea trials next summer, if I at all can, I want to sail to Montreal and back!

[@somebody1869]

@@TheDigitalMermaid we’ll be exploring lac st. Francois (the lake west of the Beauharnois locks and hydroelectric dam). This lake goes almost to Cornwall). There is some supposedly brutal current at points between Kingston and Cornwall, up near 4-5kts apparently. That’s what’s been keeping me from taking my boat into Lake Ontario as I’ve only got 15kwh. Anyways, the locks at Beauharnois are *big*. 50’ drop and apparently, the staff can be less than helpful at times. If you need help for Iroquois to Lac Saint Louis, say the word. Seaway transit to Montreal as well - the reward after that transit is stopping at Île Sainte Helene, which has an amusement park and the old expo67 grounds. The marina is super modern and has polo-shirted staff to manage your lines while docking.

[@TheDigitalMermaid]

@@somebody1869 One of the other goals I have with this channel is being able to meet people as I travel around. If / when I head out that way, I'll certainly be letting folks know, and I'd love to meet up with you and others. :)

[@sl0rion]

Welcome to Phase 3, prost!

[@TheDigitalMermaid]

Prost! 🍹

[@jimbonnett6059]

Just thinking. If your going to use the prop for regen, then a folding prop would not work! ABYC is American Boat & Yacht Council. ABYC Is a group of people who are working in the boating industries. Boat designers, boat bluiders, marine insurance, marine survey, marine lawforment (USCG, CCG, Local marine police), marine repair people, boaters and engineers ( mechanical, electrical, ect).

[@TheDigitalMermaid]

The Ecostar Autoprod is a feathering prop, not a folding one. I've got an ABYC membership, and downloaded/read all of the relevant standards, I just can't seem to get their full name to stick in my brain... lol. It's not like it's complicated, my brain just goes "Nope! ABYC is ABYC, it has no real words".

[@KevIsOffGrid]

You saying you will run a 5kw and 10kw motor, and be able to swap between as required? EDIT - yes, and that all sounds good.

[@chelleh8673]

Sounds very interesting, and you are gonna have fun experimenting and learning. I can't wait to see this phase progress and the design develop. What you said, about wanting redundancy for failure and the 5kW motor being more efficient, made me think. I know you've already got the 10kW motor, but did you consider having two x 5kW motors, running only one when that's all you need, and somehow enabling the 2nd when you need more power. Are 2 x 5kW running in parallel more or less efficient than one 10kW, when at higher power output? Then if one fails, you still have the other, and replace it when you make port and can get another shipped, maybe even just carry a 3rd as a spare, assuming that only one will ever fail at any time. It might make the cable sizes and fusing easier. I know it all adds up in cost and weight, I just wondered if this was an option?

[@TheDigitalMermaid]

I did think of 2x 5kw, but by the time the low-end efficiency thought came up, I had the 10kw in hand. The efficiency is very dependent on where I am in the power curve, but the 5kw gets over 90%, which the 10kw doesn't, so there's at least some points where 2x 5kw would be more efficient than a single 10kw, on paper. Now having the two motors running together might cause mechanical inefficiencies that eat that benefit in the real world.

[@chelleh8673]

@@TheDigitalMermaid Yeah, the mechanical complexities of enabling the 2nd motor only sone of the time, could be a problem. And generally the types of motors that allow regen, don't free-run when not energised, so you have to actively disengage them mechanically. It's a common issue in EVs and e-bikes too. It's a shame, as Murphy's Law ensures that in a system with redundancy, where one is the larger than the other, it will likely be the larger one (or the one you really need) that will fail. Although, I guess as long as one works, you can still limp to a nearest port/marina.

[@TheDigitalMermaid]

@@chelleh8673 Aye, going back to the breakdown on the Hudson, managing 3 knots would have gotten me to the next marina, albeit more slowly. The 5kw could move me at 3 knots even with 2 knots of head current, nearing max power. I'm OK with that in an emergency.

[@dc1544]

1300 lbs. battery weight wont be a factor. Your diesel engine was half that. Your fuel made up most of the rest of the weight. its close enough that I do not think its gonna be an issue for your boat. Remember to load balance so you do not hobby horse. when you build your arch the added weigh needs to be added to chain locker area. Adding 2 house banks near the Bow cabin/ anchor locker area can balance the difference a bit. so maybe even another water tank up near the bow might be needed. Again balance the weight you add on for solar arch with weigh at same spots on the bow accordingly.

[@TheDigitalMermaid]

Aye, I was trying to think it out, and I got to the point where I realized "just do it and see". Hobby horsing is another concern, too. I'll get her in next summer (I hope!) and then I can just try and see how she handles, and move things around to see if I can get her nicely balanced or not. The idea of moving the packs forward is that it would replace the ~150 liter water tank, making it about a wash for weight distribution.

[@tubeuser2350]

@@TheDigitalMermaid How about wiring the batteries as a pair of very long / skinny batteries that run along the fronts of the settees, under the seats? It would distribute the weight linearly, low and near the center of gravity. Just thinking outside the (battery) box.

[@TheDigitalMermaid]

I considered that, and it was actually a design I tried in the very early days. In my boat though, the interior space is _tight_. Losing space in the main saloon is a very hard thing to justify.

[@panospapadimitriou3498]

is it possible for a boat to have a wind generator and dump extra energy to another bank if need ? heavy but when no sun then wind wins

[@TheDigitalMermaid]

Yes, but it's not practical in my opinion. The power curve from a wind generator is very steep, and the window where they make rated power and when they need to be braked to avoid over speed is quite narrow. I've spoken to several folks with wind generators, and the output never really seems worth it. The reason I'm going so in on hydro generation is that over-speed is all but a non-issue, because the hull speed of the boat sets an absolute upper limit. So I'd rather not have the wind generator shading solar panels or taking up storage space.

[@5fxindices933]

Check out the following idea: Have both 10kW and 5kW motors permanently coupled to the shaft. For high cruising speed the 10kW should be the driver and the 5kW spinning freely. The "penalty" here will be the friction losses of the 5kW motor transmission and those of the idle spinning motor,* i.e. electrically disconnected. For getting down to 5kW "eco" mode the 10kW motor will still be the driver, but now the 5kW has now assumed the role of a generator. Doing so, you will have the 10kW running at high efficiency while recuperating the extra power. The penalty here consists of the mechanical and electrical efficiencies from the shaft to the batteries (transmission + generator efficiency + conditioning for battery charging). It goes without saying that by adjusting the generator point you can have the 10kW running at its most efficient point. The "bonus" mode will be when the 5kW motor gets switched to driver too. (*) In my language (Greek) this would be called a "crazy" motor after the technical term of crazy pulley - τρελή τροχαλία. Nikos

[@TheDigitalMermaid]

Friction losses is why I originally didn't want to parallel them, though I'm starting to think, based on comments, these losses might be very small... If so, paralleling them all the time would be back on the table.

[@tubeuser2350]

@@TheDigitalMermaid Dual motor EVs often let one motor spin idle when there's no need for the extra power and don't suffer much from the friction. I'd be more concerned about breaking a bolt or chewing up a thread if you need to swap belts around much. The less you touch the mechanics the longer they will last, and you're not going to want to be doing this in a storm (i.e. the longer YOU will last). Besides, with both motors in parallel, one can be driving the boat while the other is in regen, so you can charge the batteries at the same time... Oh, wait. :) Nice to know that the recent trip home could have been done with the post-conversion boat! And given the engine failures, with a lot less stress. Excellent video and explanation, as usual. Your channel is unique (and refreshing) in letting us peek inside your head on the decisions and what goes into them.

[@TheDigitalMermaid]

One concern about free-spinning the inactive motor is mechanical wear, also, if the drag is otherwise low enough to make it worth it... The trip home on electric is still theory for now, but I would LOVE to repeat the trip, possibly in reverse, just to prove it can be done, and silence many of the nay-sayers. ... or fail and be a great cautionary tale to arrogance. ;)

[@tx75e94]

@@TheDigitalMermaid when they free-spinning the inactive motor that motor is usually not a permanent magnet motor as they don't like to be free-spinned but a AC motor that can do that without any problems. Dual motor EVs usually use different typ of motors front and back. Your Tesla is a good example of this setup.

[@rottweiler9535]

use a cog belt drive system, gear the motor down and run it at a higher more efficent rpm range

[@TheDigitalMermaid]

Aye, leaning towards a toothed/cogged belt.

[@xpatrikpvp]

2 different multipluses won't work with vernus os... I think it would be better to keep the quattro and add a auto-transformer OR a separate 240v charger

[@TheDigitalMermaid]

The original plan was to use an autotransformer, but it would end up taking about the same amount of space and weight, and left me with another problem I didn't talk about in this video... Most electrical galley equipment is 230v 50hz, but being Canadian, most of my other gear is 120v 60hz. So I got to thinking; why not drop the autotransformer and get the two MP, and solve two problems? It also means I can pull more power from the shore, where the AT would set a cap on what I could draw.

[@tubeuser2350]

@@TheDigitalMermaid Did you see Mads' (Sail Life) video about rewiring his AC system? I commented that he should set the clock on the oven (caught flashing 12:00) and it turned out that nearly everything AC on the boat was auto-ranging and tolerated both 50 / 60 hz power. All except the clock on the oven, that is. Anyway, there might be easier / cheaper ways to do the AC system than swapping out the Quattro, perhaps with an added few-kw inverter.

[@TheDigitalMermaid]

I think so? But I don't remember the clock issue. I know it's not uncommon over here to use the power frequency as a time keeper, but it's not super accurate.

[@tubeuser2350]

@@TheDigitalMermaid I can't find the video just now (I thought it was Mads...), but the conclusion was that most devices these days don't care about 50/60 hz as a result of needing to go world-wide; they all use internal crystal clocks. It's the odd-ball that cares (e.g. his oven clock), at least in his experience. Oh, one last thought. I think a transformer also provides galvanic isolation from shore power, or am I mixing two different bits of equipment? How would a dual-MP configuration solve that?

[@TheDigitalMermaid]

@@tubeuser2350 The transformer I was originally looking at was also an isolation transformer, yes. I'm not sure if all are, I'm guessing not. In my case, I'm planning now to had a galvanic isolator just inside from the shore power connection, and then down-stream from that, a selector switch to direct the shore power into the appropriate multiplus, depending on where I am. The comment on _most_ devices being auto-ranging 100~250v AC, 50~60hz is true, but the kicker is that we do 240v by going between two phases of 120v, where euro equipment is single phase 230v. So for the things that are voltage specific, like some galley equipment, I need to the 230v AC. The upside to the two inverters though is that, no matter who comes visit me on the boat, they'll have a place to plug in. haha.

[@iMcWatch]

Is 100kw not a bit of an overkill? A windelo 54foot cat only has 54kw for propulsion and 6kw for house and that has 2 x 20kw motors or 27kw per motor

[@TheDigitalMermaid]

Overkill is best kill! Joking aside, and I hinted at it towards then end, but it might well be. I really really hope I can make it work, but I realize I may need to cut back some. If I do, well, I'll sell a couple off and use that to help fund other parts of the project.

[@iMcWatch]

@@TheDigitalMermaid well I’m really looking forward to your journey. It’s so exciting. I hate it when people say but what about the range blah blah blah. and I just want to yell… it’s a sailboat not a motorboat. There are a number of fully electric boats that’s crossed the Atlantic and some more than once. Diesel runs out that’s why people use it sparingly. On a sunny day you can refuel your electric boat in the middle of the ocean. I’m ranting 😂😂😂

[@TheDigitalMermaid]

@@iMcWatch EXACTLY! I think, with my setup, I'll have MORE effective range than a diesel equivalent, exactly because I can generate my own "fuel" on the go.