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