Motor driver

The motor driver connects the control electronics to the robot's actuators. It carries motor commands, supplies the relevant power path, and returns feedback needed by the control loop.

Useful links

Board reference

Role

• receive commands from the control electronics;
• drive the joint motors;
• route position or feedback signals back to the controller;
• expose the connections needed by the locomotion system.

Location

The board is installed in the torso-backbone area, between the central electronics and the motor wiring.

Main topics

• 2 mm header connection to the backbone;
• a connector format distinct from the analog reader;
• PCA9685 PWM generation for the 14 motors at 200 Hz;
• motor command and power paths;
• the two remaining PWM channels exposed on backbone extension headers;
• revision-specific pinout.

Poka-yoke mounting

The motor driver and analog reader use different connector formats when they mount to the backbone. One connector uses a 2x4 arrangement instead of 2x5, preventing the wrong board from being installed in the wrong position.

PWM channels

The PCA9685 drives the robot's 14 motors at 200 Hz. Its two remaining channels are made available through extension headers on the backbone for future uses.

Status LED

The motor driver has an addressable LED that can indicate the state of this board independently from the other electronics.

Pinout

Add a photo of the board with numbered pins here, followed by the completed table:

The firmware path is described in Locomotion and Hardware drivers.