Nope, you're not missing anything. I noticed that my gearboxes have play built into them that can't be removed which does result in that 'falling/wiggle wiggle year' phenomenon

Hi Joeseph, Take a look at AliExpress for ordering bolts. A lot cheaper and great selection and decent quality. If you want them fast but still at a decent price, https://www.thefastenerfactory.com.au/ is a good choice. Let me know if your in Melbourne.

I had trouble with the chain too. I ended up upgrading to a timing belt and pulley. As for encoder I didn't use any on the AR2, however I'm building a new robot that uses magnetic encoders and haven't selected the ones I'm using. This is my version of the AR2 that I made. https://www.youtube.com/watch?v=tcFbzyTCwVU&feature=emb_logo

Check this out or a starting point: https://docs.google.com/spreadsheets/d/1tWEWUX04Rhvx12vcBfraHrtZJI8M1RrX6EkvqB5PDs8/edit?usp=sharing

Hi Joseph, For sure. I buy a lot of my parts & materials from AliExpress. It takes a while to get to Aus but you get good prices and a great selection. Where in Australia are you?

Hi Myles, Yes, I mounted the AR2 upside down. I've had no problems with it. I ended up using linear rod rails with an aluminium frame. I laser cut a mounting plate but you can probably work around that.

1) Sorry, what is the "CNCCS prototype" 2) If you can use as much aluminium plate I think that is a great goal. 3) Can we see the layout?

Also a few folks have put together a google sheet

Hi Daniel, Fantastic idea, I am looking forward to seeing how it progresses. I had a quick look but I couldn't find it, but there was a post a while ago where another member was creating a board with the Mega chip integrated into the board. I think it is a fantastic idea and at some point looking forward to moving to a custom PCB board. From memory, I think he had it so it sat on top of the motor drivers directly to save more space and wiring which is worth considering. Love the idea for a Networkconnector for the Limitswitches and Connector for a 8 Channel Relayboard. Exciting.

I'd love to take a look as well. My email is paulmclaugh@gmail.com

Congratulazioni. Lavoro fantastico Thank you for sharing. I particularly like the surface finish of your parts. Would love to see more videos and photos if you have them.

Hi Peter, I'll try and lend a hand but I certainly dont have a good understanding of what your problem is. First of all I don't think you have burnt out your motor. I have had J4 run really hot a couple of times for a long time and it hasn't seemed to damage it. To be honest, I havent even pinned down why it does it but i wouldn't be too worried for now! ####The motor teeth (on no load) seem to move right. ####The arm seems to move easily (no tight bearings at the joint). ####But, with the motor installed in the arm, it is not able to budge the arm much - low power? The motor is powerful enough so scratch that off the list (unless it is burnt out). From the sounds of it I would double check that the spindle(?) from the motor isn't spinning from the gear. (ie; the motor is spinning but the gear is slipping). Easiest is just to use a marker a draw a line from the gear to the spindle and see if they stayed lined up. If not, are the other pins set to the right level? They control how many steps they are and if they are set too high that could cause problems.

@Chris Annin Will do. And thank you for the feedback. I've got the Nema 23 motor on order and a low profile gripper. As a note to others, I am running the J3 motor at 2.37A against the rated 1.68A (and the 1.46A default). It doesn't give an 'huge' power boost however is is noticeable but does generate extra heat. I've temporarily strapped on some small aluminium heatsinks which work surprisingly well to take away the extra heat. I've seen folks online use small fans to actively cool steppers which would likely increase the power capacity.

Awesome, thanks Chris for the feedback. I've ordered the sprocket & motor and will let you know how it goes. As it is inverted I'm not too concerned about adding the extra weight to axis 2 but will let you know how it all goes regardless. I've also increased the amps to J3 and it is managing fine. I've got a few meters of cable which, with the help of an online calculator, adds ~5% of power loss.

Also some additional information. You can only have one serial connection open to the arudino at a time. So if you have the serial monitor open and then run the AR2 software it won't be able to connect to it. So be sure to close the serial monitor.

I bought a pneumatic gripper from aliexpress. I bought the 16D and made a small mounting plate for it, but would probably recommend using a small one. Not bad for $45. Chris also recommends one in his build that has a smaller profile but is more expensive (a similar model is also available on aliexpress) https://www.aliexpress.com/item/MHL2-10D-16D-20D-25D-32D-40D-Double-Acting-Pneumatic-Gripper-Wide-Type-Air-Gripper-Parallel/32811013630.html?spm=a2g0s.9042311.0.0.27424c4dVhUDrn

Hey Chris, Follow up question. I've been looking into pulleys and belts but was wondering if I was overlooking something as to why I might not use a belt vs. a chain for Axis 2.

@Kris Hi Kris, I guess I should say it is a fine program, however it doesn't provide the flexibility that *I* was after. It is a fantastic starting point for sure and can be a fantastic solution. I would recommend checking out KUKA PRC (grasshopper plugin). It has been a couple years but from memory you can import custom robots and it calculates the kinematics to follow splines and stuff. With some modifications I think you could get it to spit out points that the AR2 could use. Let me know if I can answer any more questions or if you have a specific goal in mind.

Thanks for the reply. What kind of software updates were you thinking for the AR2?

I like the updated frame!