2021-09-03 Meeting Minutes - Drivetrain

Goals

• Review drivetrain timeline for the term
• Gauge each member's commitment for this term, make adjustments as needed
• Delegate current list of tasks for the prototype

Current State of Progress & Action Items

Prototype

• Mechanical assembly
  • Frame and chassis fully assembled. Wheels corrected (will reliably move with the motors now)
  • Differential bar attached, with the eye joint linkages at roughly the correct lengths
  • To do still:
    • Print and add bolt spacers on the differential bar linkages
    • Reattach the bottom, differential mounting gusset to the chassis with its spacers
    • Cut and add wheel treads
    • Print battery and weight holders, add to bottom layer of chassis
  • Learnings so far:
    • Experienced failure at the motor to the wheel shaft connection. Connected the shafts by a set screw in a coupler, without any modification to either shaft. The set screws were not able to grip onto either shaft in this state and ended up slipping. The solution: pair each shaft with a key that fits into the coupler. The set screw digs into the flat surface of the key
    • Should definitely press-fit bushings/bearings. Contributes to wiggle in the joints (i.e. at the bogie joint), and for bushings especially, ends up spinning in the plate
    • Design and manufacture with adjustability – will save time in the future
• Wiring
  • Bulk of the connections completed
  • To do still (by Sahil/Lance, who offered to help):
    • Validate that the raspberry pi will be functional?
    • Add 12 AWG ground wire from the PDB. Connect to the stack of ground connections from a mating battery cable and the PDP
    • Connect the positive wire of the mating mattery cable to the circuit breaker
    • Wire up the current sensors to the ADC and rpi
    • Wire up the motors to the Cytrons
    • Mount electronics board to the chassis via hinges
• Controls
  • Basically, starting from scratch (as per Sahil's request)
  • To do:
    • Driving RC code → Covered by Sahil
    • Wireless communication from PC to rpi
    • Collecting current sensor outputs

Update & Action Items

General Notes