Putting overpowered drive in a 150g robot!

[@k1ll3rvc]

Static pressure (axial) fans tend to want most of the area covered by blade area, so more blades generally is better. Centrifugal are far better suited for pressure, and work better with small clearances to prevent recirculation of airflow around the edges. The exit from the fan might want more area, it looks pretty small compared to the intake area, but that should be easy to test with different fan diameters.

[@JannisDohm]

maybe also worth trying out different skirt positions. Changing the area which contains the under pressure could also help :)

[@TeamPanicRobotics]

Thanks for the tips, what I'm hearing is: More blades More exhaust Tighter clearance (its currently 0.5mm) Better skirt These are all very doable! I'll have to give them a shot

[@rudycandu1633]

@@TeamPanicRobotics I don't know (literally) if more exhaust is needed because you are looking for suction and not high flow volume. I would look at how vacuum cleaners fans are built. A skirt is good, but I wonder if TPU will cause it to stick/drag on the surface. I would go for the bottom surface to be low friction.

[@TeamPanicRobotics]

I could do a hdpe skirt, that would be low friction

[@k1ll3rvc]

@@TeamPanicRobotics the more blades was based on the three blade prop, the centrifugal impeller looks reasonable. Exhaust comment is purely by eye, deffo test that as it may be good. Clearance will be a trade off, don't want things to collide when you take a hit, but fan performance is generally better with less clearance. Adding a ring to the open side to stop the fan flexing at speed will help, can't remember if that was already in the plan.

[@MrBubba123bubba]

I enjoyed you including the things that did not work instead of just cutting the video to look like everything was perfect the first time. I feel like perfect videos can discourage people starting out.

[@TeamPanicRobotics]

I'm glad you enjoyed I like showing when things don't work, because that's always part of the process

[@repeatrobotics]

Super cool robot! Very excited to see how it does!

[@TeamPanicRobotics]

Its been through some rough fights now, the fight report should be interesting

[@CenReaper.]

~5cm Lego propeller producing 293g of trust on less than 2000 RPM be like: take my beer 🍺.

[@TeamPanicRobotics]

Oh interesting! is there a test video on youtube somewhere? the last time I looked at lego propellers, the brick experiment channel got like ~140g out of 2 very large fan blades and made a drone with them If there are smaller better lego propellers it would be great to find and test them

[@razer259]

Oooh, Downforce making a comeback as well! Should be fun to watch! I've had my eye on another motor from Repeat Robotics for some time. I should probably contact this guy to see what he can do to ship to Aus. Here's hoping the Downforce is strong with this ant. 😁

[@repeatrobotics]

We’ve shipped a few packages to Australia! Send us an email

[@axeami1354]

on the suction side it may pay to place a wall covering the blades of the impeller leaving a hole in the center, it should make it harder for the impeller to draw air from the top thus making it more efficient.

[@TeamPanicRobotics]

I'm not sure I'm following what you're describing The impeller has a wall around it, close too but not touching the blades, with a bit of extra diameter at the top to allow air to escape

[@amadensor]

I'm just impressed that you made weight with 2 brushless ESCs.

[@amadensor]

Or was it 3 with the fan?

[@TeamPanicRobotics]

3 with the fan! its quite the squeeze

[@tamrobotics]

Sold! I'll buy these now for my upgrade

[@SuhJae_]

Can't wait to see an update on the competition! Wish you best luck!

[@hunterovitt4426]

this is one of the most unique and interesting videos from the hobby battlebot scene I have seen in a while! keep it up!

[@TeamPanicRobotics]

Glad you liked it!

[@KNfLrPn]

In your tilt test, with the motor off you're just measuring the coefficient of static friction between the chassis and table. With the motor on, the vibration breaks the static friction and kind of turns the vehicle into a hovercraft, making it drift downhill regardless of how much the tilt is. To measure the down-force, the easiest way would be to get a pull scale with a max hold function, use it to pull the vehicle off the surface, and subtract the vehicle weight.

[@Teth47]

IMO the test is sound, his goal doesn't require a measurement of total downforce so much as total *grip*. Grip would be a function of vibration as well as total downforce in this case, so designs less prone to vibration would rightly compete better, particularly if they're somewhat robust to damage.

[@TeamPanicRobotics]

I like the pull scale method, I have one for luggage but I dont think its sensitive enough for 150g scale robots. I'll have to see if I can find a better one I think with a few changes (electronic angle gauge, more repeatable plate moving) this test would work a lot better. I might have to do a deep dive into impeller designs at some point and use both testing methods

[@sando5943]

​@TeamPanicRobotics I would love to see just a simple test of the robot pushing objects of different weights with and without the impeller. I imagine that would replicate its final use case a give a better idea how much it helps

[@thomasoltmann8933]

Jumpscare at 0:36 :o Cool challenge idea though, looking forward to the fight video.

[@kingofl337]

You should smoke-test the vacuum to see how air is moving through the robot. It will help ensure it is moving the air as expected.

[@TeamPanicRobotics]

Thats a good idea!

[@BonafideShaynanigans]

That drive asymmetry issue drove me nuts a couple weeks ago. Its a quirk with blheli_s, it seems to slightly prefer going forward. I fixed it by setting one to bidirectional and the other to bidirectional_reversed in the configurator.

[@TeamPanicRobotics]

AHH! that would explain it! My TX is set with one channel reversed due to other hardware I run (and being too lazy to set up different models) So one will be going backwards I'll give the bidirectional_reversed trick a try, Thanks!!

[@oscarrafiq9506]

In the niche instance of using more than one brushless motor in a 150 gram robot, it may be worth looking into a quadruple esc often used in smaller drone stacks. I am currently trying to make a full brushless 150 gram ant on one of these.

[@oscarrafiq9506]

It may also shave some weight with a small enough one

[@TeamPanicRobotics]

I didnt know you could get small ones, the only ones I'd seen where 40A ones with a pretty big foot print, I'll have to go looking

[@sea_kerman]

@@TeamPanicRoboticsthere are 20x20 and 16x16 ones in addition to the “normal” 30x30. I know Flywoo makes a 16x16.

[@TeamPanicRobotics]

Wow! 16x16 is impressive for a quad esc, that would certainly solve the space issue

[@sea_kerman]

@@TeamPanicRobotics note that the amp ratings are likely not correct for your use case, they’re rated assuming that they’ll have constant airflow

[@Alex_.The._Conqueror]

I wonder whether making a melty brain bot that has structural fan blades to produce downforce while melty-ing would improve handling or speed

[@TeamPanicRobotics]

I have considered this, I'm not sure it will work but I've got an idea on how to test it

[@davidorbell5803]

to check the downforce you need to place only the wheels on the scales and the resr of the robot on a flat surface.

[@TeamPanicRobotics]

Would that only measure the downforce at the wheels?

[@davidorbell5803]

@TeamPanicRobotics Yes, but that's all you really need it on, isn't it ? for the drive

[@CenReaper.]

There is an Arduino compatible electronic traction control that you should try for your robot.

[@Lusidous]

After looking at the size and speed of the motors, the first thing that came to my mind was melty

[@TeamPanicRobotics]

I do want to make an ant melty at some point!

[@thomashp]

Add a dab of glue or epoxy to those motor wires where they come out of the motor. They are tiny and once they come out, they don't want to go back in.

[@emaloney_]

Yes, a video on how to program the BLHeli 32 S would be great. Please assume beginner level if possible.

[@TeamPanicRobotics]

sure thing! I might program a few more before I make a video because the drive needs some tuning to work better

[@codyphillips1821]

I'm excited to see this in combat

[@polarationmotion948]

Loved this video and the concept of a high powered wedge robot. I was just curious if turning the Impeller in the opposite direction would result in a sort of lifting weapon or even flipper?

[@TeamPanicRobotics]

Not with this design, the impeller sucks air from below and blows it out the top regardless of spin direction

[@СоюзниксОкинавы]

Thinking about overpowered motors, why not just build a 150 g version of Deep Charge from NHRL?

[@TeamPanicRobotics]

because I and the EO's at my local club disagree with Depth Charge style bristlebots getting a weight bonus. The weight bonus is intended to make walkers and shufflers more attractive to try, by offsetting the extra weight those systems need. Its definitely against the spirit of the rule to use less weight for your drive, and whack all the extra weight into your weapon Also I dont need to bend the rules to make robots with stupid big weapons, I've build a 150g robot with a 77g blade on top, all without using a weight bonus for an unintended purpose (which is a big part of the fun for me, the challenge of fitting something crazy into the smallest weight limit) I get depth charge is chaos and fun to watch, but its not for me, I'll get similar chaos my own way

[@ironoreiron]

Can you make a 150g combat bot with the Flash hobby 12A esc Edit: if you already have one, can i have a link for that vid please

[@TeamPanicRobotics]

Why that one specifically? It looks to be virtually the same as any other

[@ironoreiron]

@@TeamPanicRobotics well is it even good? Its like the only 12a 3 in 1 esc i found on amazon

[@TeamPanicRobotics]

I dont know, I dont own one and havent used one The one I saw in a quick google didnt look like a 3 in 1 esc, it looked like a standard single motor brushless esc

[@ironoreiron]

@@TeamPanicRobotics interesting, also, team just cuz robotics said that brushless escs only work with brushless motors and brushed escs only work with brushed motors, but in your easiest spinner tutorial video you used a brushless esc with the brushed n20 motors?

[@TeamPanicRobotics]

That is correct, brushless escs only work with brushless motors In my easiest spinner tutorial video, I used brushed n20 motors from dfrobot that have an ESC built into them. They are linked in the description I used them because they are lightweight and easy to use for a beginner

[@СоюзниксОкинавы]

Try to make something like road roller.

[@davidorbell5803]

can you reverse the thrust of the propeller to make it a flipper ?

[@TeamPanicRobotics]

Not with this design, the impeller sucks air from below and blows it out the top regardless of spin direction

[@davidorbell5803]

@TeamPanicRobotics yes but if it was the propeller version, it might work 🤷‍♂️

[@turnabot7307]

Acetate skirts?

[@TeamPanicRobotics]

Ohh yeah! definitely one to try