WOSO

Hello KevinH49:We used left and right window motors that have a machined mount to the robot.The timing pulley was machined to have the right ID to press over the motor gear and then we JB welded them together. It is still holding and this arm has been in the hands of thousands of middle schoolers. Our biggest mistake is that we didn't know that the center pin did not rotate so we had to grind out some glue. We got our motors from our school's robotics team, but I am sure you could get some at your local junkyard, or machine building shop in just a few phone calls.As we used a pulley to translate the power to the main robot rotation shaft, the end of that shaft had a potentiometer mounted to it. We used a 360 degree absolute magnetic encoder from US Digital, but you could use a continuou...

Hello KevinH49:We used left and right window motors that have a machined mount to the robot.The timing pulley was machined to have the right ID to press over the motor gear and then we JB welded them together. It is still holding and this arm has been in the hands of thousands of middle schoolers. Our biggest mistake is that we didn't know that the center pin did not rotate so we had to grind out some glue. We got our motors from our school's robotics team, but I am sure you could get some at your local junkyard, or machine building shop in just a few phone calls.As we used a pulley to translate the power to the main robot rotation shaft, the end of that shaft had a potentiometer mounted to it. We used a 360 degree absolute magnetic encoder from US Digital, but you could use a continuous or 3 turn, 10K pot.

Booyah! This is how we do it. I am so happy to have played a small part in your success. You made a beautiful robot that looks to have performed extremely well. Great work, you deserve this success!

If you are in the prototyping stage it is most likely amechanical issues. When working with bread boards, I try to solder male headersonto all wires to resolve any loose connections.Try isolating the problem. Upload code that just allows youto control the wrist when you turn the wrist pot but keep everything pluggedin. If other parts still jitter then I would look into a power issue. Maybe youare loading down the system and there is not enough current. When you mixservos sometimes you can create "dirty power" follow the link forsome solutions!https://www.dimensionengineering.com/appnotes/video/video_tutorial.htmI hope this helps, it is all about going back to basics andisolating the problem as you expand up again.