The Motor Controllers

by Web FishMar 16, 2013 @ 12:34pm

Controls the direction and power of the propulsion pods. Translates the central processor decision making and the battery power into mechanical movement.

  • Current selection: Pololu Simple Motor Controller 18v7
  • Status: Undecided (under testing)

  • Criteria: Max current handling, standard I/O, small physical footprint, thermal footprint, cost 
  • Finalists: Pololu RoboClaw 2x5A Motor Controller, Arduino Motor Shield R3, SeeedStudio Grove Motor Driver 
  • Main decision factors: High sustained / peak currents, cost, standard serial bus interface

 (click image for larger view) 

Spec highlights:

  • Simple bidirectional control of one DC brush motor.
  • 5.5 V to 30 V operating supply range.
  • 7 A maximum continuous current output without a heat sink
  • Four communication or control options:
    • USB interface for direct connection to a PC.
    • Logic-level (TTL) serial interface for direct connection to microcontrollers or other embedded controllers.
    • Hobby radio control (RC) pulse width interface for direct connection to an RC receiver or RC servo controller.
    • 0–3.3 V analog voltage interface for direct connection to potentiometers and analog joysticks.

 

Caveats:

  • Still unclear if we will use UART or PWM to control the boards. We are using 2 pins either way;
  • If using UART, both boards will be chained;
  • Unclear if hat signature will be an issue until we mount in the navionics bay with the rest of the electronics modules;