Computer

The Pi runs the relay and the robot. Your laptop runs the controller. Both use one deployment file, so they agree on the relay's address and neither file contains the other's devices.

The Pi

Install Raspberry Pi OS and the same Python environment as Installation. The robot process imports the project, so the project has to be on the Pi: clone it there, or mount it. Then, on the Pi:

pip install -e .
pip install "solarian-feetech[hardware]"
sudo apt install python3-picamera2

Create the Pi's virtualenv with --system-site-packages so picamera2 from apt is importable. The camera chapter is the one that opens the sensor. Installing the package now means you are not debugging apt in the middle of calibration.

Plug in the USB-serial adapter with the servo supply off. Find the port:

ls /dev/ttyACM* /dev/ttyUSB*

A Feetech adapter usually appears as /dev/ttyACM0. Unplug it and run the command again if you are not sure which node it was. Remember the path. It is the path from the Pi, not from the laptop.

A deployment file

conf/deployment/localhost.yaml is still the file Tutorial 2 uses, and you should leave it that way so simulation on the laptop keeps working.

Copy it:

cp conf/deployment/localhost.yaml conf/deployment/lab.yaml

Edit conf/deployment/lab.yaml. The IP is the Pi, because the relay runs there. .local works when mDNS does.

connection:
  ip: robot.local
  action_sender_port: 5555
  action_receiver_port: 5556
  state_sender_port: 5557
  state_receiver_port: 5558
  clock_sync_port: 5559

actuator_port_right_arm: /dev/ttyACM0
actuator_port_right_gripper: /dev/ttyACM0
camera_port_right_wrist_camera: "0"

The arm and the gripper share one bus, so they share one path. The camera port is the CSI index.

Copy the file to the Pi as well if the project is not a shared checkout. Both sides read it.

Power on, torque off

Turn on the servo supply, then the Pi. You should hear nothing from the arm. The project does not enable torque until a program asks it to. If a servo twitches at plug-in and stays slack, that is the bus enumerating. If it drives to a stop and holds, unplug the supply and check you did not leave a vendor utility commanding it.

From the Pi, with the project installed:

solarian feetech-inspect

You want IDs 1 through 7 answering. A missing ID is a servo still set to the factory ID, or a wire. Fix that before calibration. Calibration talks to the IDs in the YAML, and a silent ID looks like a dead joint.

Next: calibrate.