You realise I got a better mic for £30?

Yeah, but a final video on this would take it to like Part 30. So this will take years.

Guess credit for the design is Jeff, but your contribution helps immensely. Thanks again!

@@jaredgray7872 Check out the latest flex spline design of the actuator I'm now using. It's even better. kzfaq.info/get/bejne/atVjl5qQvMDDdIU.html

You should check out latest part of the build kzfaq.info/get/bejne/atVjl5qQvMDDdIU.html

Check out the new anti-backlash 50% better torque small stepper motor actuator at www.thingiverse.com/thing:3566678

Working on it +Mikael! The next step now that the actuators are assembled is to get the electronics going. Using ESP32's in each joint to generate stepper pulses and then will use ChiliPeppr's Cayenn protocol to upload all Gcode moves to each joint. Stay tuned.

@@JohnLauerGplus thanks for the answers keep up the good work. Very interesting content. 👍

Wow..... this is really good job. I hope your effort easier access to robot technology for anyone around the globe. #globalpride

@@mohdyuzairin8719 Thank you.

@@JamecBond not if you want a touch sensor in each actuator for record and playback. Also, they are $3 each. That's so cheap you can sprinkle them everywhere. Also, running wires is a serious problem and this avoids that.

Totally agree

Totally agree

Interesting. I am working on a BLDC version of the actuator now. I'm printing the new compound planetary gear in nylon and indeed I am breaking in the gears by running them raw against each other and it is smoothing them out. However, what lapping compound would you use for plastic to make this process faster/better? I can't find any when you search google for "3d printed gear lapping compound".

@@JohnLauerGplus Loctite has a brand called "Clover." I'd say a nice 200-300 grit would do it. The Lower the grit the more abasive and faster, but finish is not as pretty... higher grits will give a smother, prettier finish, but take longer. After the gears quieten, remove and clean them thoroughly. Add real grease and they will be perfectly mated! THIS is old-school gear perfection!

I was worried about that. I searched online and couldn't find much data on the correct lubricant. If vaseline breaks down the plastic, then indeed something else should get used. I'll try the white lithium grease like you suggest.

@@JohnLauerGplus I definitely second the suggestion of white lithium grease. You'll commonly find it used in joysticks and things because it's plastic-safe. 👍

I thought the same.

I believe it depends on the type of plastic, some plastics react to it and some don't. Would depend on what type of filament he used for the print.

Can't go wrong with silicone grease. Used in distillation lab equipment because of how little it reacts with other chemicals.

Yeah that's what he said, the model is in english "imperial" however the nema holes are in metric

Good idea. It would add some height to the system, but probably could make the cover be 0.6mm height, so wouldn't add much. Those planetary gears do rub along the top where those nuts are. The top sun gear does push itself up towards the roof of the gearbox. So do the planetary gears, so the smoother the roof, the better. A cover could help that be even smoother than having those nuts exposed. As I've seen the grease squeezes up into the nut holes over time. Although, I do think it makes sense to have some gunk repositories where over time the shreds of plastic can bunch up and get pushed into depressed areas to help give longevity.

Ooh. Tell me more. It would be nice to have an even stronger gear reduction box. This one is decent, but the robot arm could be much stronger. Do you have any links to any designs? Or videos you've done? Or concepts?

@@JohnLauerGplus not yet but hopefully will have something to share in a few months or so. I'll shoot you a link once I'm ready to share it with the world :) probably via a Kickstarter if prototyping goes as planned.

@@JohnLauerGplus in the meantime check out Jeff's new design kzfaq.info/get/bejne/qcqCetWFrdeYmHU.html

That's so funny. Although the video is all about the robot arm, I do think the table behind it helps glorify the whole thing.

Yes, i think i messed up putting the larger motor in the base. I caught that too. Good eye.

Thanks!

🤣 i thought the same and ... 3:33

silicone based would be best

Cool, what's your agriculture robotics project? I'd love to see more of an open source community sprout (pun intended) around this design so we all benefit.

@@JohnLauerGplus I'm looking at a "something" to select and pick up fruits. Initially.

If possible, I would like to share in private. May be through Linkedin. Thank you.

I am now using PETG on my latest design as you can see in Part 3 kzfaq.info/get/bejne/atVjl5qQvMDDdIU.html, but I am hearing robot guys using 3D printing like the flex on PLA better for gears. I'm not quite sure yet.

And, part 3 is now posted kzfaq.info/get/bejne/atVjl5qQvMDDdIU.html

I've been using a raft to print these gears so that the gear teeth are perfect. The downside is the raft makes that first layer on the actuator parts not look pretty. I probably should do those as a separate print job without a raft.

Then you should watch part 2 and part 3!

John Lauer thanks John! Subscribed!

I don't think steel balls would work much better, but perhaps. Didn't try it, but I think steel against plastic may wear in an odd way. Plastic against plastic seems to wear nicely. Also, these bearings turn out really tight yet smooth rotation, so that's not the part of the design I'm worried about. What I don't like is the power of the stepper motor.

Latest design now has a hall effect endstop. I'm getting about 500 Hz PWM signal to stepper driver before these 35mm steppers freak out. It's looking like 1lb could be achieved, but I'll be doing a payload measurement in Part 4 video in the future. Here's Part 3 now. kzfaq.info/get/bejne/atVjl5qQvMDDdIU.html

It can carry 1 pound.

@@JohnLauerGplus what would be the possible changes for 4 pound payload.? Motors and higher reduction ratios I guess?

@@sharath_naik yes, I think that would be the trick but you may have to move to metal to do that.

Don't have it working yet. The electronics aren't easy.

That's a cool idea, but those need to be really smooth, so that would worry me you'll never get the smoothness and roundness that you need. Albeit you are sort of averaging them together, so maybe it "mostly" works?

I will say in subsequent designs I just went with cheap off-the-shelf metal bearings because they're worth the simplicity, smoothness, and tightness beyond a 3D printed bearing and they're not that expensive on the low end, but 10 times better than a 3D print bearing.

I've been very happy with the ender 3. However I did have to replace the extruder plastic parts with aluminum ones because they cracked

So far the arm is like $95. No, doing this in metal would be very hard given the intricate details. Maybe 3D metal printing could work, but the weakest point isn't the plastic, rather it's the stepper motors. So the material doesn't matter as much as you think. Going stronger would require more gear ratios. Harmonic drive would be amazing if we could all figure out how to print a harmonic drive.

Yeah, you can use any motor you want, but you'd end up redesigning the 3d parts a bit for fit. If you do try out a NEMA 14 and rework any of the CAD, could you please share it because even I would like to see some stronger motors on these actuators so we have choice. The stepper motor driver in this design is 2A capable so the electronics are ready to go for bigger motors.

Indeed... I found it a little amusing when he talked about liking the Amazon PLA printed at a high temperature better than the hatchbox PLA. He's got printing issues that are much more important than filament choice.

True, I can't imagine that choice, but that's personal preference. Insane temperature for basic pla too. I print Amazon at 200 and it comes out beautiful on any of my printers.

I printed all my prints on rafts, thus that first layer which you see on the top of the cap are the remnants from that. All of my other layers turned out perfect. I have tried printing without the raft and I do get problems on the 1st layer being squeezed. I've dialed that in better since shooting this video. I too think printing PLA at 235C is very high and there are complaints about the Amazon Basics, but it does end up more rigid than the Hatchbox which prints fine at 200C.

You are correct in your assumption. It creates the torque you need. The extra benefit is you get better accuracy too because the steppers are 48 steps per rotation, but now you control 48*38.6 positions per rotation.

@@JohnLauerGplus thanks for your timely reply

Print the gears at 99% or even 98% then.

@@JohnLauerGplus Thank you

Backlash is minimal given how tight these gears are fitted. Those airsoft BB bearings don't move laterally at all, so they're pretty decent. You'd be surprised how little backlash.

And now the latest design has an anti-backlash flex spline in the actuator to help solve backlash. kzfaq.info/get/bejne/atVjl5qQvMDDdIU.html

I took your suggestion and got the white lithium grease. I'm using that now instead of vaseline. Thanks for the idea!

There will be 2 power wires going to each joint. They're not wired up yet. I may end up with a sync signal wire as well unless I'm happy with the Bluetooth or WiFi command sending being close enough on timing.

BTW, check out my new approach of doing a slip ring in the actuator for the 20v power so this turns out to be a zero wire robot. I'm not perfectly happy with it yet because I get some blips on the power, but it may pan out if I can get the design tweaked. kzfaq.info/get/bejne/atVjl5qQvMDDdIU.html

Because wiring robots is a huge pain and I need/want a temp sensor in each actuator, fan controller, hall sensor for end stop, ws2812 LED for status, and touch sensor for local jogging and programming. We now know how to run signals over the air, rather than needing copper, so can eliminate many wires that way. ESP32's are dirt cheap and a novel way to go these days. Yes, it's all theory until it comes together, but might as well give it a go.

@@JohnLauerGplus thanks man

@@williamalkhoury3417 Part 3 shows you it all coming together--thus answering your original question. kzfaq.info/get/bejne/atVjl5qQvMDDdIU.html

Yes, I agree. That base should be raised by about 0.5mm or even 1mm to sink the M3 screws further. The downside is the sun gear height is exactly the shaft gear height to get full contact, so you'd end up with the sun gear 0.5 or 1mm higher, but that probably is an ok tradeoff.

@@JohnLauerGplus Nope, no trade off at all. shit the base of the PG system by making it a little thicker to compensate for the inner nut cover. that way everything inside stays the same length.

I think it would be interesting to look at options for bearings, but the way these actuators are all integrated is very nice and trying to get an off-the-shelf bearing in there may not be as elegant. However, I'd love to see if anyone could CAD out a potential design.

Well, I just ment to use plastics sliding against each other. Without any real bearings.

@@CinemaTablet I don't think that would be smooth or friction-free or tight enough. Ultimately you do have plastic against plastic since those airsoft BB's are plastic.

i don't think casting would be precise enough

They're in the description.

Yeah, it's going to get controlled by chilipeppr.com from Gcode. However, since this is a six axis plus gripper design, you'll have to train it by moving it into a position, snapshot that position to create a line of Gcode, and then play it back. That will be done from ChiliPeppr.