(feature): Add support for koch screwdriver robot and teleoperator

[jackvial]

What this does

• Adds a new follower robot koch_screwdriver_follower that replaces the Koch gripper with a screwdriver driven in wheel (velocity) mode.
  • New implementation, dataclass config, docs (.mdx), and package init.
• Adds a matching teleoperator koch_screwdriver_leader.
  • Maps leader-side gripper motion to follower-side screwdriver velocity (close ⇢ clockwise, open ⇢ counter-clockwise).
• Wires the new types into the CLI entry-points (calibrate, teleoperate, record) and the make_*_from_config helpers.
• Dynamixel bug-fix: exposes Present_Position / Goal_Position for XL330-M077 table to avoid 4-byte range error.

IMG_4136.MOV

---

Screwdriver Hardware

The screwdriver STL files and bill of materials can be found at https://github.com/jackvial/koch_robotic_arm_screwdriver

---

How It Was Tested

Recorded dataset

https://huggingface.co/datasets/jackvial/koch_screwdriver_thread_checker_06_e20

Calibration

# Follower arm
python -m lerobot.calibrate \
  --robot.type=koch_screwdriver_follower \
  --robot.port=/dev/servo_5837053138 \
  --robot.id=koch_screwdriver_follower_testing

# Leader arm
python -m lerobot.calibrate \
  --teleop.type=koch_screwdriver_leader \
  --teleop.port=/dev/servo_585A007782 \
  --teleop.id=koch_screwdriver_leader_testing

Teleoperation

python -m lerobot.teleoperate \
  --robot.type=koch_screwdriver_follower \
  --robot.port=/dev/servo_5837053138 \
  --robot.cameras="{ screwdriver: {type: opencv, index_or_path: /dev/video0, width: 800, height: 600, fps: 30}, side: {type: opencv, index_or_path: /dev/video2, width: 800, height: 600, fps: 30}}" \
  --robot.id=koch_screwdriver_follower_testing \
  --teleop.type=koch_screwdriver_leader \
  --teleop.port=/dev/servo_585A007782 \
  --teleop.id=koch_screwdriver_leader_testing \
  --display_data=true

Recording

python -m lerobot.record \
  --robot.type=koch_screwdriver_follower \
  --robot.port=/dev/servo_5837053138 \
  --robot.cameras="{ screwdriver: {type: opencv, index_or_path: /dev/video0, width: 800, height: 600, fps: 30}, side: {type: opencv, index_or_path: /dev/video2, width: 800, height: 600, fps: 30}, top: {type: opencv, index_or_path: /dev/video6, width: 800, height: 600, fps: 30}}" \
  --robot.id=koch_screwdriver_follower_testing \
  --dataset.repo_id=jackvial/koch_screwdriver_thread_checker_${TEST_NUMBER}_e${EPISODES} \
  --dataset.num_episodes=${EPISODES} \
  --dataset.episode_time_s=30 \
  --dataset.reset_time_s=5 \
  --dataset.push_to_hub=true \
  --dataset.single_task="Move towards the M4x0.7 thread near the top of the red metal thread checker board. Then screw the silver screw into the M4x0.7 thread, then unscrew it again but not all of the way. The screw should still be partially in the thread. Then move back to rest position on the wooden block, with the screwdriver bit facing towards the shoulder servo." \
  --teleop.type=koch_screwdriver_leader \
  --teleop.port=/dev/servo_585A007782 \
  --teleop.id=koch_screwdriver_leader_testing \
  --display_data=true \
  --play_sounds=false

All commands completed successfully and produced the dataset linked above.

TODO

• Calibration procedure docs
• Hardware printing and assembly tutorial