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ORCA: Optimized Robot for Chemical Analysis;



  • 5 (6) Axes; [1] Longditudonal motion along rail, [2] 1st lat. joint, [3] 2. lat. joint, [4] 3. lat. joint, [5] 1. rotational joint, [6] 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
  • dentical components.
  • 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.



Motor Control Board Guts:

  • MC68HC711E9CFNE2: MCU, 8BIT 12KB OTP ROM 2MHz 52PLCC
  • L4960: Switchmode controller, 2.5A 9-46Vin 5V Out
  • SN75176A: Differential Bus Transceiver
  • DA05P: ESD Protection Diode Bridge
  • 74HC4538: Dual retriggerable precision monostable multivibrator, probably for RS485/something timing alignment
  • LMD182003A: 55V H-Bridge
    • Inputs: Direction, Brake, PWM
    • Outputs: Thermal flag, Analog current sense
  • 82C54: CMOS Programmable Interval Timer
  • TL7705ACP: Voltage Supervisor
  • HCTL2000: 12/16-bit Quadrature Decoder/Counter



125000, 62500,

Hints to comms protocol:

  • 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.

Inspiration:


Control Box DB-15 Connector

PinConnection
1GND
2DP/DN
3GND
4VA
5VA
6VA
7VA
8NC
9DN/DP
10GND
11GND
12VB
13VB
14VB
15VB


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