5 (6) Axes;  Longditudonal motion along rail,  1st lat. joint,  2. lat. joint,  3. lat. joint,  1. rotational joint,  1. Finger/Gripper.
Almost certainly 24V power supply
<5MBit RS485 multidrop bus to all three control boards.
Axes [1,2], [3,4] and [5,6] have their own control boards with differing layouts but nearly i
There is a separate 2-board (probably) inclinometer board attached to the 2. lateral joint. Every joint consists of a brushed DC motor with axles protruding from both ends, with significant gear reduction on one side and a Honeywell glass disk encoder on the other.
Supposed to have Force and Torque feedback for at least fingers, maybe all joints. Video online of the robot painting and moving batteries corroborate this, Each 2-joint motor control board probably runs a PID-ish control loop, possibly with full motion control loops but perhaps just point-to-point with motion parameters.
4 near identical modules communicating via a <2MBit RS485 multidrop bus
MCU has one UART (SCI):
Datasheet §7.3; NRZ signaling, simple data format: Idle high, start bit 0, 8/9 bit packet LSB first, stop bit 1, break period of 0-bit strings for at least 1 frame.
Datasheet §7.1 Table 1; Baud rate table: 8MHz Crystal → 2MHz Bus. There are 32 possible rates, but something really standard,
Probably means multi-packet instructions, 8 bits for both operation bits and data bits seems insufficient.