Rick has some integrated sensors that can be accessed through it’s API
MMA8452Q 3-axis, 12/8 bit accelerometer connected on the 1st I2C bus.
By convention, the axes of the accelerometer are re-mapped in the API from their manufacturer assignments onto the standard robot frame of reference
(x forward, y laterally left, z vertically up). These are marked on the PCB.
Motor Current (“Force”) Sensors
A 0.1 Ω 1206 resistor (Schematic ref. R7 to R14) is attached from the Servo low-side to ground, and then to a GPIO on U1
for all motor channels except channel 9 (used for the Eyes). This permits motor current sensing, as a proxy for exertion/force/torque.
Note that add-ons such as the Raspberry Pi Camera don’t interact with Rick
so aren’t documented here.