Step 2: Replace Files (7-DOF Adaptation)
1. If You Cloned from the Official Code Repository, Which Files Need to Be Replaced/Modified
Option A: Use This Repository's Code Directly (Recommended)
Option B: Manually Replace Files in an Official lerobot git clone
Copy 3 files from this repository over the official clone:
| This repository's file (source) | Overwrite to (target) |
|---|---|
src/lerobot/robots/so_follower/so_follower.py | The same-named file in the official clone |
src/lerobot/teleoperators/so_leader/so_leader.py | The same-named file in the official clone |
Prerequisite: your official clone has the same structure as this repository's baseline (lerobot 2026-09 version).
If the versions differ greatly, do not overwrite the whole file; instead make the two "manual changes" below.
Manual Changes When Versions Differ (Only Two Places)
① Motor dictionary (one copy each in so_follower.py and so_leader.py, identical content) — change the original
"wrist_flex": Motor(4, "sts3215", norm_mode_body),
"wrist_roll": Motor(5, "sts3215", norm_mode_body),
"gripper": Motor(6, "sts3215", MotorNormMode.RANGE_0_100),to
"wrist_flex": Motor(4, "sts3215", norm_mode_body),
"wrist_yaw": Motor(5, "sts3215", norm_mode_body), # new servo, left/right rotation
"wrist_roll": Motor(6, "sts3215", norm_mode_body), # original #5 roll motor, ID 5→6
"gripper": Motor(7, "sts3215", MotorNormMode.RANGE_0_100),② Calibration logic (the calibrate() in each of the two files) — remove the "full-turn joint" special case: change
full_turn_motor = "wrist_roll"
unknown_range_motors = [motor for motor in self.bus.motors if motor != full_turn_motor]
range_mins, range_maxes = self.bus.record_ranges_of_motion(unknown_range_motors)
range_mins[full_turn_motor] = 0
range_maxes[full_turn_motor] = 4095to a single line, changing it to record the real range of all joints:
range_mins, range_maxes = self.bus.record_ranges_of_motion()Why: the original code hardcodes
wrist_roll(rolling around the forearm axis) as a joint that can turn full circle (0~4095) and sets the full range. After the 7-DOF modification, wrist joints #5/#6 (yaw / roll) both have mechanical limits and cannot turn full circle; forcing the full range would make the code send joint commands to angles the mechanism cannot reach, with a risk of damage. Now calibration records the actual min/max of every motor manually.
Bi-Arm (Dual Follower) Notes
bi_so_follower / bi_so_leader (src/lerobot/robots/bi_so_follower/, src/lerobot/teleoperators/bi_so_leader/) merely wrap the single-arm classes with a left_/right_ prefix and contain no motor definitions. As long as the single-arm files above are modified, the bi-arm commands (--robot.type=bi_so_follower) are automatically 7-DOF.