v3.0

[Armandpl]

• diy slip ring, avoid having to have an arm above the robot
  • use bearings?? https://cults3d.com/en/3d-model/tool/collecteurs-tournants-electrique-slip-ring resistance might be way too high? but we only need a tiny bit of current? will it be noisy?
  • https://www.youtube.com/watch?v=XTPcSdeAd2Q
  • PCB slip ring + sliding contacts (keywords: fingerstock, spring finger, te connectivtity)
• pcb rev2:
  • header to be able to swap (+extend) xiao samd21
  • 12V -> 5V to power the xiao samd21 without usb, so that we can deploy in a standalone way
  • M3 mounting holes to reduce the number of screw types?
  • labels for the motor power connector, motor header and pendulum header
  • connect xiao samd ground, connect tsx0108e OE pin to 3.3v
  • get the right bent dupont headers
• can we make it smaller and cheaper? can we use a smaller motor?
• drv8871 has been discontinued, find a replacement
• motor is $50, encoder is $20, seems really expensive can we find cheaper alternative?
• how robust is the direct shaft mount for the arm? will it wear down quickly? aim for ~100hour of testing?