Drone Generator Performance

[@antonnym214]

excellent work here! I am especially impressed by how still the glass of water is. You've done an amazing job.

[@TechIngredients]

Thank you!

[@BrokeWrench]

2 strokes are very sensitive to exhaust design. They need a tuned resonator to run well, the only downside is that there is a very small powerband. Thankfully your generator will operate at one specific speed.

[@kguidry7520]

Right. I was curious what the hole pattern would do to the sound. It's basically like a bunch of firecrackers going off at the same time. Each exhaust cycle emits a group of pops instead of a rumble. Small holes are black cats. The bigger holes are like M80s. The previous muffler had tuned pipes with a far less obnoxious sound. I think even the neighbors would agree. Impressive machine. Solved a lot of problems for those looking to build hybrid fuel/electric systems. Great knowledge for free. On behalf of the greedy world, thanks.

[@dennisford2000]

Both intake and exhaust can be tuned, and it would be interesting to see what the ports look like. Often small 2 cycles leave a bit to be desired in design and such .

[@justinlawlor3898]

I was just gonna say this exact same thing, it was my first thought wheb I saw his shit exhaust

[@davelowets]

@@dennisford2000 They sure do... In my opinion, a properly designed tuned pipe for the rev range it operates in, would make the largest "bang for the buck" improvement in efficiency, then followed by a little port clean-up.

[@dennisford2000]

@@davelowets exactly. See the word tuned , that would be tuned just below the required rev , so torque will increase if the crank slows

[@victoryfirst2878]

I watch this channel because you cover literally all the bases of topic discussed. Something that most other videos just somehow miss or go awry. Please continue to make these great informative videos for us all to learn from and be able to tell others to watch with confidence. And again, keep on making these videos !!!!!!!!!!!!!!

[@TechIngredients]

I will. Please share these videos to help us grow. Thanks!

[@davidpuissegur1263]

Thankyou for taking the time and effort to post this video. Forty years ago the only way we would have been able to see a video on this high of level. Would have been to watch NOVA on PBS. Now thanks to KZbin and individuals like yourself we can just surf KZbin. The video on sound cancellation was brilliant. Can't wait for your next posting.

[@davida1hiwaaynet]

Very nice generator set. This fascinates me since I work on large gensets for the offshore oil & gas industry. It sounds so consistent, as well! The only thing I worried about was the engine cylinders overheating since the fans are blowing down, over the ends of the cooling fins and not through / between then as the original propeller airflow would have. Not complaining! Just an observation. All my generators are water cooled. :) Glad you tested by hand and found they aren't too hot! On our big gensets, the governor tuning is a very important part of the unit. It's got to be interesting tuning the Arduino to govern the engine based on voltage output. I hope you have / will go over that part of the build! Thanks again!

[@michaelkhobbs741]

I wanna thank you for all the cool videos that you made. You remind me of the cool science teacher who kept me interested in science and creating with my own hands most of my life. I think we are all being tested in ways that make me question my own reality. One thing for sure is I know myself and my reality and values are still holding strong. I really watched all of your videos sometimes 2 3 and 4 times. Thank you so much for everything.

[@GreySectoid]

As a fellow engineer, I can only say you did awesome job here.

[@lewsdiod]

Amazing as always. Thanks for the great and very educational content. I feel I see parts of the world with new eyes after binging your channel :)

[@TechIngredients]

That's a very interesting way of putting it. I am frequently confronted with how many people see the world so much differently than I do.

[@craigc6769]

Watched it to the end with the same smile. Very impressive. Useful to me for a UAV alternator on my fixed wing.

[@rhyoliteaquacade]

I think there needs to be a paradigm shift with resoect to hybrid quad copters. Instead of using the gas engine/generator to provide all of the energy for verticle propulsion, it should provide energy mostly to power a directly coupled ducted fan. Secondarily electric fans would provide vectoring and station keeping. This way, only a smaller amount of energy would need to be generated for a smaller battery complement. The ratio of gas powered thrust to electric could be worked out to best attain the amount of altitude control and efficiency. My interest is with high endurance platforms contain radio relay (repeater) equipment where longevity is the major concern. Secondly a power source for the repeater in tens of watt hours. What do you think of this approach? Can the engines be throttled efficiently?

[@davelowets]

I don't think the throttle response of the engines would be fast enough to get good control over the craft. The P.I.D.'s in the electric control of a quadcopter are INCREDIBLY fast in keeping it stable, and the resulting lag between the microprocessor and the eventual throttling up and down of a gas engine would be way to slow to reliably control it. I'm guessing a gas powered generator and electric powered props are the way to go, even with a central prop just to provide lift... I could be wrong though. 🤷🏻

[@consaka1]

I love that. Probably the coolest hand warmer I have ever seen. 24 amps is nothing to sneeze at.

[@davelowets]

Depends on which voltage the 24 amps is delivered at.... 😜 1 volt at 24 amps is only 24 watts. Watts is the better unit here to describe power output as amps can mean a little, or alot, of power depending on the voltage. 🍻

[@garyh4458]

You're wearing a Members Only jacket. I think you are actually a time traveler and that is why you know so much about advanced technology.

[@TechIngredients]

I'm the next ACTUAL Dr. Who.😀

[@Barc0d3]

One of the best channels on youtube on this category! I really love your work!

[@jonnoMoto]

Have you tried the fuel consumption with the original exhaust? I have a feeling that the box exhaust is restrictive and not helping efficiency.

[@SetMyLife]

Exactly what I'm thinking. Connecting the two exhausts together increases the effective exhaust pressure, decreasing pressure differential needed for "scavenging"

[@seeker1015]

Yes, two strokes just thrive on tuned exhausts, I'd be going for a compromise exhaust. Fuel efficiency Vs Db. Plenty of 2 stroke info out there on exhaust tuning science.

[@robmorgan1214]

Yes. This. Been there done that. Proper exhaust design is key with two strokes.

[@mihaiilie8808]

We dont know what he hides in that box exhaust 😂.

[@janrobertfiksdal2171]

Great video! We are interested to buy one of your generators when you are done testing and making videos. We really like the way yiu present stuff. Only a small idea that I have is to put a voice over after.

[@FatherOfTheParty]

Very interesting! Amazingly vibration free. Very professionally done. Thanks for sharing!

[@HuguesD]

Nice project. There is something that I still do no get right. Considering the amount of power required for even a modest 900mm (15-16" props) - 6kg AUW class X8 drone, which requires 2-3 KW range in hover, I wonder how this engine-generator setup could be of any practical use as it must weigh multiple times the weight of the said drone while producing only about 750 watts. Or did I miss something ? What's the total AUW weight, fuel included of this engine-generator setup ?

[@stinson87]

I did basic calculations and using a pair of smaller 2.2hp 2 stroke motors and 1500kw motors for the generators, the breakeven is at 4.76kg.... For these motors and generator, and frame, you need a massive drone, and the generation is no where near useful. I think he needs more generator head on the motors.

[@BurstNibbler]

Loving the beverage glass on the worktable. I'm partaking as I'm watching!

[@alancalvert953]

Very nicely done sir! And I like your Members Only jacket. I have one also. I guess we are the last members of that club. Keep up the good work

[@tonygristina8372]

The look at 9:15 is priceless. I had that same look when Mommy first praised me for pooping the toilet.

[@hermit3400]

Is the ultimate goal to lift the entire APU into the air with the drone, or will there be long wires connecting the APU and the drone? What will the finished APU weigh? Excellent channel by the way! I am recommending it to family and friends.

[@TechIngredients]

Thank you! The APU will be carried by the drone, below the batteries. The final weight has yet to be determined. It needs the enclosure to be added in place of the temporary wooden base plate and the 80/20 supports for the fans.

[@hermit3400]

@@TechIngredients Wow, that is very exciting! I'm really looking forward to your future videos. I guess heavy lift really does mean HEAVY LIFT!

[@SilentGloves]

Great video, really enjoying this series. Cheers!

[@ms_vibe9918]

Amazing project! ive learnt more from this man than I did from my engineering school. i will like to amback on this same project for my drone but i have a question sir, what if the gasolin engine quits mid-air? I have experienced alot of 2stroke engines quiting on me. lost my last drone on 2stroke efi engine quit.

[@TechIngredients]

Thanks! Use the generator in conjunction with a small battery. If wired in parallel, the battery maintains charge and even acts to smooth voltage ripple. If the engine quits the battery will allow you to land.

[@ms_vibe9918]

@@TechIngredients Thanks !!

[@chrissmith2956]

Love this video and the Members-Only jacket!

[@juliocosta5818]

I have a members only underpants ;)

[@khal3610]

WOW,,thanks for having your site. Im gong over all your videos and the motors are sold out so, how does one calculate esc to motor to power details for a perfect balanced system? Thanks Keith

[@TechIngredients]

Start your design as a cyclic process. Determine what you want the drone for, where will you store it, how to transport it, how long will it fly and how fast? Do you want the lift efficiency of 4 huge rotors or the redundancy of 8 smaller ones or a balance of 6? How much will this rough idea for the design weigh? How much can you spend and how much are you able to fabricate? Find the components for this first iteration and then REPEAT. Each time you run through the loop you will fine tune the choices and you will have spent only time. The ESC that best matches the motor that you decide on should have a significantly higher current rating than you expect to need. They all tend to run hot. I like KDE. The regenerative braking improves responsiveness especially for large drones. www.kdedirect.com/collections/uas-multi-rotor-electronics

[@Araye]

If you're running nitromethane, a good percentage of the "fuel" is oil to lube the engine. All that oil is going to end up in your glass sponges. If you subtract the oil content from the weight, you'll find your efficiency is a little better. Those mufflers are going to be fun to keep clean. Cool project.

[@TechIngredients]

These are two stroke gasoline engines with only two stroke oil added. And, thanks!

[@mckenziekeith7434]

Weighting the exhaust system before and after is a thought, though. Two strokes have smoky exhaust. Maybe there is particulate accumulation.

[@Araye]

The oil in the nitromethane fuel (Mr. Tech told me he's using gasoline and not nitromethane, but same principle applies) doesn't burn. It is exhausted. The reason it doesn't burn is that it is added to both lubricate and cool the engine. All of that oil will saturate the glass and be a mess to clean up. This system, coupled with Mr. Tech Ingredient's experience in noise cancellation, should have lead to a muffler that is ported in such a way that the noise from the first exhaust is cancelled by the second. The arrangement he has here is perfect for this type of system. Anyway...

[@sailingcapedissappointment2012]

Lol I saw a video of one of those glasspacks melting and spilling piles of moulton debris, looked kinda like a volcano ....

[@cvspvr]

some of these 2 stroke rc engines can be run with as little as 2% oil

[@insomniactuber92]

I was wondering if there is a specific reason that you opted for twin vertical cylinders instead of a horizontally opposed boxer configuration. Assuming equal reciprocating mass in both engines and 180 degree timing, it seems like a boxer configuration would be able to achieve proper balance without adding counterbalance to the flywheels. I may be wrong, but I believe that the flywheels could be made significantly smaller on any 2-cylinder 2-stroke with 180 degree timing compared to a single cylinder engine. With two opposed cylinders, the power stroke of each cylinder directly drives the compression stroke of the other, which reduces the need for flywheel momentum to carry out compression. So, you may have some opportunities to save weight there. Can't wait for the next update! Keep up the good work!

[@TechIngredients]

The more powerful, 4 cylinder, 222 cc boxer version of this engine does solve this problem, the twin does not. We have this larger engine and indeed it produces less vibration. The flywheels were not sized to prevent vibration, but to smooth the power stroke and reduce the voltage variation.

[@insomniactuber92]

@@TechIngredients Great to know, thanks!

[@dominik8040]

@@TechIngredients do You plan to finish idea with active / passive noise cancelling box for this engines? How does it performed?

[@gogogeedus]

You sir are heading in the right direction, i could see this type of tech on full scale passenger carrying aircraft, keep up the good work and i hope you inspire some people to get off their buts and do some stuff, including me : )

[@gogogeedus]

Not electric with generators as far as I know.

[@gogogeedus]

I mean electric is great but the range is not good, the technologies has advanced and the only limitation is range,batteries are heavy so the answer must be efficient light weight generators to charge the batteries in flight. I could see small jet turbine being used ultimately or even turboprops that are boosted by electric motors to increase their responsiveness and generate electricity.

[@gogogeedus]

sounds like the APU would be perfect for E/Planes.

[@gogogeedus]

OH YER!

[@jclowe735]

That's very interesting. Did you buy or salvage the generator/motor and what's the displacement of the gas engines? Would something like this work on a bicycle to make it a hybrid like for long trips?

[@TechIngredients]

It sure could be. I'd build it much smaller as we demonstrated in the follow up video. This unit puts out over 2kw.

[@freeelectron8261]

Nice work! Good power output using brush-less multi-phase motors as generator (rectified and filtered for DC output). Very low vibration.

[@TechIngredients]

Thanks!

[@mvadu]

You should have changed(varied) the resistor banks while system is running to show the Arduino based feedback loop and battery stabilization. Otherwise this is TheOldTony of electromechanical channel. Thank you for your time and hard work.

[@michaeldallas]

Good info. So, the weight of the generator plus the weight of the fuel is far less than the comparable weight of lithium batteries with the same energy content?

[@TechIngredients]

This all depends on how much fuel you carry. If the fuel to battery energy density is 10:1 then the weight of the generator, being fixed, will determine the break even point. Less fuel then don't bother and the more the fuel the more advantageous the the use of a generator.

[@stinson87]

Based off a setup of two small 2.2hp motors and 15kw gen heads, rectifiers, and mounting, breakeven is 4.76kg, not sure about his weight here.

[@glasslinger]

Probably using 4 engines with props and servos controlling the throttle to the flight controller would be vastly more efficient. Also, the capability of smaller drones is really getting phenomenal, such as the DJI Mavic series.

[@TechIngredients]

You're right about the small drones. As to the larger multi rotors (where a separate generator module has any potential application), reconfiguring the existing machines would be an expensive project. In addition, gas motors have a greater lag time, making control a little courser. The noise is harder to contain with distributed engines and the vibration associated with these engines is harder to isolate when they are coupled directly to the air frame.

[@mircoheitmann]

i would worry about stability btw. i'm used to PID loops of a couple khz on miniquads with bldc motors, but for one the servos should slow the response time down and the combustion engines are most likely even slower. i'd also wonder if you could use less than four combustion engines to power four (or more?) motors to save cost, noise, vibrations etc.

[@davelowets]

I agree... The stability control loop would be WAY too slow with gas engines on the props. The P.I.D. stability loop runs at several kHz for the electric motors. A gas engine would never have the required response time to make it stable. I think if one were to try and use an I.C.E. as the prime mover for each of the propellers on a quadcopter, a very complex system to control the pitch of the props along WITH the throttling of the engines, much like a helicopter would be required. Just imagine the flight controller software and hardware needed for THAT... 😕

[@rhiantaylor3446]

Just wondered if you could use the generators to perform the function of the flywheel on the engines i.e. do you need both ?

[@joseluisureno444]

Thanks for sharing this videos! I think you’re doing an excellent job with your design, the way you couple the motors to minimize vibration is brilliant, no doubt you will get the power you are looking for. The one thing I don’t like is the design of the mufflers. two cycle engines need exhaust scavenging to reach pick efficiency, it would be awesome to see this generator run with a tuned pipe in each motor.

[@TechIngredients]

We looked at these and they tend to be bulky.

[@jamesfenton7338]

@@TechIngredients bulky maybe, but worth every gram. Fuel consumption will drop, and available power can be optimized. 4600 rpm should be within the stock tuned pipe range, and it will be quieter. You can do whatever you want with the pipe downstream, but, the tuned section is critical.

[@huaahhggg9507]

Tech Ingredient's departure from scientifically maximizing function and, in this instance, choosing to prioritize form is a little disappointing.

[@adriaan7627]

If the current delivered is that constant it is interesting how the 4 stroke engines would perform in the same kind of setup. 1:10 versus 1:20 is considerable. The propellors of the drone are driven by electric engines. So it would not be problematic that the engines deliver less of constant power throughout the 4 strokes instead of 2 x 2 strokes. Not sure if I describe it correctly. Hope you understand.

[@gooblio]

I was just thinking I want to know how the vibration is and you put the water in the glass, good show old man.

[@mickjc75]

It's awesome. But why didn't you compress your audio track?

[@sailingcapedissappointment2012]

2 stroke motorcycle engines have a full circle crank and the racers do what they call stuffing the crank to boost performance and reducing vibration is a large part of performance optimization and this goes on in high end chain saws as well. I noticed that Boston dynamics is using a pulsejet engine in thier robots, these engines are much lighter.

[@mikewashere9660]

Tech Ingredients .. Thanks very much for your contributions! Rare are the persons that give without asking for doe, or that beg for money ... I'm sure you understand better than I can explain! anyway.. Thus far you're the first person doing uploads on youtube using RC engines for generatoration of power, I am very ignorant of electrical systems, but have often wondered if one could use RC electric motors as a generator source, i.e., use a .50 nitro RC engine to turn something like a 520Kv motor, if you'd obtain a substantial amount of of power to charge a couple 12v deep cell batteries, (time constraints/issues) and in turn use the deep cells through an inverter to run power for a home, I'm sure it would need to be "sized up" to run anything more than a high efficiency refrigerator, but with so many trying to make their own mag-motors/generators, RC has them already made for cheap, considering how much neodymium magnets cost! Your thoughts sir? Again, much thanks! Respectful Regards and Salutations, Mike

[@TechIngredients]

Thanks for the comment. The limitation on airborne generators is weight. If not constrained by weight then diesel, solar steam etc.would be a good choice along with high field magnets and intelligent controllers.

[@ufobrownsugar7948]

So precise and articulated!

[@waltergrimm7161]

Two motors this size generate 700 watt of electric power, I was assuming that these small motors deliver for over 1 to 2 kw, what will be required to lift the whole contraption with load by design? Sorry if I might have missed it in a vid, I would assume that it is too little

[@TechIngredients]

If you look at the follow up video, we pushed the system output beyond 2kW.

[@waltergrimm7161]

@@TechIngredients thank, I am a great fan of your liquid descasant air con, I believe this would be viable

[@causer13]

Thank you for the video. I really want you to continue this series about the hybrid drone. And I think there are many of us want so. Would you by any chance continue this saga? If not, could you please say a couple of words about why did you decide to abandon this project?

[@TechIngredients]

We didn't abandon it. There is just so much we want to cover and only so much time. We need staff!

[@jeanguion3223]

Those little engines rarely ever come with correct fuel jetting... Leaning them out will help... Also you could dissasemble the cases and fill in all the extra nooks and crannies with jb weld or a similar material , then machine or sand them smooth... Less extra case volume equals less waste...smother running too... These engines also rarely come with a proper squish area in the combustion chamber... You could mill the heads down some...increasing compression..and run the motors a little leaner still... You should also check out the youtube channel "2-stroke stuffing", about porting small 2-stroke engines...he'd probably even port some stuff for you... Proper porting for your purpose built engines would go along way toward efficiency... Btw..I really enjoy your ptojects..super good channel..

[@jimrennison1]

Truly modern Two Strokes use a porting scheme that results in a stratified charge. You can identify them because of their windowed piston and dual intake carburetor. Both major chainsaw manufacturers, Stihl and Husqvarna, produce these engines in great numbers anywhere from 30 to 100 cc's. Their purpose is to reduce emissions but as a side benefit you get dramatically lower fuel consumption.

[@photonthief]

This is a fantastic video series! Thank you for sharing!

[@maximummarklee]

Thinking out of the box brings a turboshaft generator to mind. They are not cheap, and I don't have a list of your requirements or budgetary constraints, but if you use a turboshaft with reduction gears driving a generator, it would give you a pretty good place to start, since you can calculate the optimal size components that meet your needs. It would also be pretty cool if you ended up with a hybrid setup that uses both electrical and output shaft power to run the machine.

[@nicholasthon973]

Because a multicopter would need an engine for each propeller set. 4 or six engines would be unreasonable.

[@clintonandrews1538]

For efficiency and weight conservation, it would seem that an Achates Opposed Piston Opposed Cylinder (OPOC) engine would maximize efficiency and minimize weight. What do you think?

[@TechIngredients]

You're probably right, but obtaining these may be the major problem.

[@CShand]

I have done alot of work on this myself wanted to say that if you want to improve efficiency use mosfet rectifier over diodes you will have to build a circuit for any amount of current you get out of it.

[@davelowets]

And what advantage do you think a mosfet would provide over a diode?

[@h82sk8]

I expected to see the wine glass move. Seems smoother then expected. Good job but I think your tuned pipe needs another revision. :) May I recommend a common secondary manifold and vertical muffler attached to the original tuned pipes. Brass and tin is easier to solder for this purpose too!

[@donbeckham]

The wine glass is hot glued to the base. Take a close look @1:52.

[@h82sk8]

Now I'm wondering what purpose the wine glass has. Did you happen to catch that too?

[@donbeckham]

Yeah, to show how smooth the motors were running. He talks about the balancing challenges in previous videos. You'll notice when he fills the glass with water, it's very stable. No low frequency vibrations, otherwise the water would have been all over the table. But,, it's a little misleading because there is still a high frequency vibrations, which are very apparent when he begins to pour the water into the glass, you can see the cavitation in the water @8:15.

[@astbrnrd]

Are you going to produce a "limited run" for market testing? About how much would you make these for (USd$)? Awesome progress you have made, very excited of the development. Thanks for the update!

[@besearchingforwisdom6267]

What do you think about a hybrid drone with a rocket to get the drone to altitude initially and then the battery pack is coasting the motors for the flight allowing a longer run time to?

[@paulbergin4239]

Very informative stuff. Thanks for all the hard work.

[@joseportela205]

Thanks to you to help us to understand the world

[@DavidAstronaut]

This is for personal flight ?

[@freewheeler58]

Could you elaborate a little on the specs for the upgraded generators? Have you had any issues with non-sinusoidal (trapazoidal) waveform generation? Why the shift away from a hobby RC motor/generator?

[@TechIngredients]

The waveform has not posed any issues as it is close to sinusoidal at the operational frequency of the generator. I'm not sure what you mean by a shift away from hobby motors.

[@freewheeler58]

Sorry, I mean what was wrong with the original black generator you were using?

[@gogogeedus]

you don't have to worry about transition, you can set them at the optimum settings for the requirement and forget, you might want to idle them down for a little while before shut down

[@raydreamer7566]

Great great videos. Oh 2 stroke motors don't like boxy mufflers...They need a sonic blast back to help contain the new charge of fuel input.

[@wacio]

One suggestion. The exhaust system replacement may be causing scavenging fuel losses. Exhaust needs to be tuned (length) to provide optimal fuel flow thru scavenging... This may improve efficiency by few %.

[@davelowets]

A properly tuned pipe for the rpm range would increase efficiency alot.

[@nicholasthon973]

Have you analyzed the output with an oscilloscope to hone the necessary electronics for reasonably controlling the dc?

[@TechIngredients]

No, we have not. We did use the scope for simply determining the pulse frequency, but not for evaluating the voltage/current phase relationship or that relationship's dependency on frequency.

[@MS-bh7ok]

so you plan to fit the whole contraption on a drone to power it in the air...?

[@freejulianassange3143]

Great work and thank you for posting! With all of the dross on the internet these days this is a real pleasure to watch.

[@TechIngredients]

Thank you.

[@claudbase]

For the cooling, could a multi blades EDF type fan be integrated in the center of each flywheel?

[@TechIngredients]

Probably.

[@claudbase]

@@TechIngredients To save weight, the generator rotor could be used as a flywheel (if needed, "pancake" type generators would provide a larger moment of inertia). A rigid coupler could be used to connect the two axes and the generator stator could be fixed to the engine mount with a flexible vibration damping rubber mount.

[@paulladdie1026]

Excellent interesting video, keep it up!

[@KD0CAC]

Maybe not part of your drone project ? But I have always thought of having a gas turbine powered generator , and other items . Thanks

[@RevAldea]

You will need to give the fuel weight per volume for plaining the fuel tank placement within the airframe. Fuels do change depending on location and time of year weather foundering of the fuels used in it but volume does not change.

[@TechIngredients]

It's best to locate the fuel tank as close as possible to the center of gravity to avoid changing the balance of the craft as the fuel is consumed.

[@Alexander_Sannikov]

Again, how does overall energy density of this system compare to energy density of a battery array of the same weight?

[@TechIngredients]

I'm not sure if I addressed this with you before, but assuming I haven't, the energy density depends greatly on the fuel quantity. The weight of the generator module is fixed. As the amount of fuel carried increases, the energy density of the combination increases to the limit of ten to twenty times that of the battery.

[@petertaylor3424]

What is the purpose of the noisemaker .

[@knutem2155]

RE Sound & Weight: Considering your great Helium videos, is it possible to enrobe the motor in a layer of Helium?

[@TechIngredients]

The motor/generator, yes. The engine is much more difficult because of the need for high air flow for cooling. The application ,as we see it, is to use helium to fill extremely light panels that make up the enclosure.

[@matthewzelek9871]

I’ve been wanting to build a hybrid drone for years! Have you considered attempting to recover some of the energy lost as heat by using thermoelectric generators?

[@TechIngredients]

No. The added weight for an airborne application wouldn't be worth it.

[@rkaid7]

Would a typical 4-wire O2 sensor allow you to close loop the mixtures for increased efficiency? Would an expansion pipe on the exhaust allow you to move peak torque to the "set" RPM?

[@TechIngredients]

Yes to both. The O2 sensor will need to be part of a fuel injection system in order to reap that benefit.

[@linusgk5042]

Shouldn't it be possible to start the engines with the generators? Then you can have a loud muffler and go in to "stelth" running only electric when needed? Also, dooing an extraction exaust might increese the efficiency! Hope to see it in the air soon! BTW! love your videos, im suprised that you dont have more followers, you seems really smart! Getings from Sweden.

[@TechIngredients]

Thanks! What do you mean by extraction exhaust? Is this the same as a tuned exhaust? Starting with the generators as motors is certainly possible. It would only require some high current switching (some mosfets) and a feed back controller to switch the circuit as soon as the load decreases.

[@tomgeorge3726]

Hi, thanks again for a good video. How are you relating fuel consumption to generated power? I'm not sure what you mean by 20 to 1 and 10 to 1 ratios.

[@TechIngredients]

These are ratios relative to the energy available in Li ion batteries.

[@Laser2999]

Hi, I would like to ask you what do you think about the alternative method to produce electricity using Fuel Cells, can it be an efficient solution?

[@TechIngredients]

Absolutely. The problem at present is the cost of the ion membranes necessary to generate electrical current from the reactions.

[@BoilerBloodline]

Love the Members Only jacket!

[@rustyfarkel]

Have you looked into a new type of engine called "Liquid Piston" Its a rotery style with three exhaust ports that don't require mufflers. They produce large amounts of HP in porportion to their weight. I don't think they are on the market yet, but are on youtube.

[@TechIngredients]

I have. They are very expensive and the manufacturers are not very helpful about the commercial availability.

[@shahabkhodadoust7152]

Thanks to you. Good job. Exciting.

[@MartinGallacher]

How about using a gas engine(s) to generate most of the lift (>80%) using props and then using conventional battery motors for remaining lift and control, which would then be simpler and fuel efficient? If the gas motor quits, you could still land the craft using the reserve battery power left...

[@TechIngredients]

That is an excellent idea. There are a few KZbin videos that show this dual lifting scenario. This will be more efficient than converting the engine's output into electrical power to drive the lifting fans. The trade off is that the noise and vibration will be harder to isolate.

[@N914TJ]

I just watched your video where you talked about nearly losing your eye to a Roman candle. You said safety is a 24/7 job. The present video would have been a good place to demonstrate that philosophy by wearing some hearing protection.

[@kokopelli314]

Trying to read your power outputs on the blue screens. Suggest a fixed camera for these. Also total kwh output per fuel used will give an efficiency number.

[@jasonmillner6416]

is that 10 to 1 figure consider the weight of the generator? and if so how much fuel weight/generator weight?

[@TechIngredients]

The generator is a fixed weight and therefore is not added. However, because it is fixed the 10:1 advantage only begins to manifest with longer flight durations.

[@claudbase]

Could a small gaz turbine be used instead of the 2 strokes engines? Less efficient, but a better power/weight ratio... Also the higher RPM would mean a smaller & lighter generator could be used for the same output power... Finally, by orienting the turbine exhaust downwards, it would lift more then the combined turbine and generator weight, lowering the electrical power needed to keep the drone airborne... The only problem left would be to find a way to mitigate the horrible turbine noise, without killing its performance...

[@TechIngredients]

You could use a gas turbine, but as you said it's substantially less effecient and much more expensive. The high RPM will be too high to couple into most motors without burning them up unless a lower speed turboshaft output is used.

[@claudbase]

@@TechIngredients After re-thinking this problem, I believe that the optimal solution would be to use a large propeller attached to a two stroke gas engine that would take care of 80 to 90% of the needed lift, while letting the 4 electric motors take care of the missing 10% to 20% lift + pitch/roll and yaw control during the flight. This way, the generator, DC/DC converter, diodes... would be much smaller. Relatively large airfoil profiles attach to the quad lateral vanes and correctly oriented would eliminate most of the torque of the gaz engine, while the other 4 electric motors could compensate for any residual torque. The cooling of the gas engine would obviously be also solved.

[@frankklever5950]

It was really stable. The water had almost no ripples. Awesome!

[@jugulator3767]

Great video, I was hoping you would pour a Belgian Dubbel into that glass though. :)

[@adriaan7627]

Seeing this wineglass, I thought you would enjoy some wine during the testing ;-)

[@BadMooseRecords]

You need back pressure to get a 2 stroke engine to work. You should really put the original expansion chambers back, they are most likely tuned for the motors. The exhaust gasses need to travel back to the cylinder to get it running good.

[@TechIngredients]

A tuned exhaust is supposed to help, but the supplied exhausts were no better than our modifications, the originals were probably not tuned.

[@t395delta]

stand still, look smug, nailed it :-) and one more sub, nice work

[@verbon5434]

Great video. Thanks.

[@free_spirit1]

9:40 on the left there is an allen wrench falling off the table, seemingly due to vibration?

[@TrentTationnaiseXization]

Heard it but thought he had bumped it off.

[@camaro92026]

It's been 3 years! any progress?

[@jesusisalive3227]

Very cool! I'm planning on building a 10th scale rc car using this same type setup.

[@ashleyarundel3134]

Hi There, what happened to this project? Was it unfeasible?

[@gizmoguyar]

This is really cool work, don't got me wrong. I love any and all engineering of new devices and technologies (I'm a mechanical engineer myself). But I feel like the hype and buzz over "Drones" has caused a lot of people to lose sight of the big picture. Helicopters are a very mature technology that are gas powered, very efficient, can fly for a long time, etc. "drones" i.e. multirotors, are really only good for small electric devices. A friend of mine in college made a gas powered quad copter that worked fairly well, but there really just wasn't a good reason to do it. Once you get above about 10-15 lb. or so, just use a standard gas helicopter design.

[@SithaSek]

But helicopter is not easy for maintenance. When crashed in accident not easy to repair. I use drone for agriculture and now a lot of chinese drones had this system on board.

[@davidfalgout7304]

sub'd and thumbs up! I wish we lived close together ..... no doubt together we could create a device to exceed all the watts produced in "back to the future's Delorean". Great Job!!!

[@faheemfawzi947]

Hi sir, i would like to know how you design and size the flywheel? thank you!

[@TechIngredients]

Its mass approximates the mass of the piston and the rods and its diameter was a practical decision based on clearances.

[@faheemfawzi947]

@@TechIngredients Thank you!. How and what material do you use to offset the flyweel? I see that the flywheel itself is made of aluminium, how about the inserts to offset the flywheel inertia? I can see there is at least 2 or 3 inserts? Correct me if im wrong.

[@TechIngredients]

They are simply steel discs that counter the offset mass of the piston and placed 180 degrees away from the piston.

[@nnamrehck]

I'd like to know how he got avgas for his generator. I didn't know you could buy such a small amount.

[@TechIngredients]

Sure, you can, but avgas is the is very similar to automotive gas. We're using ethanol free gas.

[@muntee33]

Thanks very much for sharing 👍🏻

[@jimmiemcdonald6051]

i have noticed that your load resistors are all in parallel. how would the voltage and current compare to two in parallel in series with two in parallel?

[@TechIngredients]

The resistors were wired to give approximately 1.5 ohms of total resistance. This relates to the kv of the motor-generators. At a fixed RPM, which is determined by the engines, the kv determines the current output for a given voltage drop. A lower kv will produce more current, but will load the engines more heavily. If the kv is too low, the engines are unable to reach their maximum RPM and total power output is reduced. If the kv is too high, the engines will reach red line before they generate the maximum potential power output.

[@jondavidmcnabb]

I imagine with a well designed exhaust diffuser system and a good engine baffle surround this would be a reasonably quiet system.

[@mckenziekeith7434]

Instead of turbo-charging it, I think it is worth considering using an electric motor to super-charge it. To me, that seems easier and more controllable.

[@JimLahey21]

Your wasting free exhaust energy....