Jerry Li

i build robots, drones, e-bikes and more | mech e @ uiuc '30 | DMs open

[Jerry Li @jerryli_design]

i'm jerry, a mechanical engineering freshman at uiuc. i build robots, drones and electric vehicles. this is where i'll be posting them!

[Jerry Li @jerryli_design]

@Rose_M_Leo just finished my first month of college, but this was a project i made in high school hence the hallway testing

[Jerry Li @jerryli_design]

this electric vehicle i made travels 8.3 meters in less than 3 seconds with only 1.1 cm of error.

one drone motor drives all four wheels to accelerate as fast as possible. the motor's geared 1:6 to the rear axle, and the rear axle is belted 1:1 to the front axle

i made the chassis lattice out of 1.5mm G10 fiberglass and designed it with FEA to decrease torsional rigidity by 72%. this is so that the chassis can flex over bumps so that the wheels stay in contact with the ground for as long as possible, meaning the encoder reading of the wheels is more accurate to the actual distance traveled

rn the magnetic encoder reads off a shaft thats geared 1:5 from the drone motor. i originally had the encoder read directly off of the motor's shaft, but it spun so fast (~5k RPM) that the arduino's loop times were too slow to handle the wraparound logic, so rotations would get miscounted

full write up is here!
https://t.co/Q7KOvd39se

[Jerry Li @jerryli_design]

@Code3ks @IlirAliu_ thanks!

[Jerry Li @jerryli_design]

i'm jerry, a mechanical engineering freshman at uiuc. i build robots, drones and electric vehicles. this is where i'll be posting them!

[Jerry Li @jerryli_design]

@merlinofnigeria if you have questions feel free to shoot me a dm, and youtube has so many great resources!

[Jerry Li @jerryli_design]

this is a hybrid drone-rover that i made that can attach and detach

the drone can carry the rover and vice versa, and they can also separate into two independently operating agents.

to reduce weight i used only one actuator to move 10 different parts through 6 spur gears. the rover can also catch the drone without power: there's 4 elastic doors that spring out of the way and snap back onto the drone.

almost every part of the rover is 3D printed out of PLA and can be made on any hobbyist printer.

check out the full write-up here: https://t.co/9b4kqKzFLV

[Jerry Li @jerryli_design]

@open_erv yeah, lowering speed solved the skipping but youre right that theres not much margin. i always prefer closed loop haha

[Jerry Li @jerryli_design]

this is a robot i made that automatically swaps the build plate of my 3d printer. it extends with timing belts driven by 2 stepper motors, sucks the plate with 4 electromagnets, and turns with a pulley on the bottom.

the video's sped up 4x, a cycle takes ~70 sec because the steppers skip if i try to go faster. this is because the magnet on the printer bed is insanely strong lol

currently it uses a button at the bottom to trigger it to change the build plate, but i think wireless would be better. thinking of setting up MQTT on a pi zero that subscribes to the printer's topic to know when its done

i got a lot of attention for my first video and i'm excited to keep sharing my work! thanks everyone 🙏

[Jerry Li @jerryli_design]

@Glubux i tried both masking tape and adhesive PEI sheets, both worked pretty well, slightly less reliable than stock pei sheets

[Jerry Li @jerryli_design]

@s2010m33 thanks! not too familiar with tooldance x1, how would the pallet changer work with it? most CNCs have workholding etc, unlike a printer which has a build plate thats pretty easy to remove

[Jerry Li @jerryli_design]

wow nice! did you find that using electromagnets had benefits over grabbing with some mechanical grasping mechanism? my electromagnets are 5kg each but they still required custom build plates, because the stock ones wouldnt stick to the magnets. they were too thin and had too thick of a PEI coating

[Jerry Li @jerryli_design]

@kdpisda good idea, ive seen automation systems where they do that to release the part and just scrape off the part but yeah would be helpful to reduce the magnetic pull strength too!

[Jerry Li @jerryli_design]

this is pretty commonly done especially with bedslingers, however some bigger parts have a lot of adhesion to the build plate which makes them difficult to remove off of the plate, so i chose to replace the whole plate
if i had a print farm and was automating production of a few models around the same form factor, something like that would probably work very well

[Jerry Li @jerryli_design]

@merlinofnigeria yeah i'll be posting explanations of my projects here, also feel free to dm with any questions. would recommend youtube too since thats where i learned most things, so much free knowledge there

[Jerry Li @jerryli_design]

@Code3ks @IlirAliu_ great, my dms are always open!

[Jerry Li @jerryli_design]

@sergiosuave23 i appreciate it!

[Jerry Li @jerryli_design]

@PlanitiaCorp thank you so much, wishing you a speedy recovery🙏

[Jerry Li @jerryli_design]

@UtahMaint thanks so much!

[Jerry Li @jerryli_design]

@Chela_Barbeito thank you!

[Jerry Li @jerryli_design]

@Diplomatt42 thank you!

[Jerry Li @jerryli_design]

@wizardofid haha thank you!

[Jerry Li @jerryli_design]

@i_am_onkar yes, this is true. many different ways to grasp the plate, would be interesting to test some of them

[Jerry Li @jerryli_design]

@i_am_onkar the plates are metal but they have either pei sheet or just masking tape on them, so it may not work as well