Upper-Body Teleoperation

com.bxi.upper_body_teleop is a standalone Elf3 Mod. It bundles PICO access, MediaMTX, head-camera RTSP, Pinocchio dual-arm IK, and its runtime libraries. It only requires com.bxi.basic_actions; the legacy bxi_teleop_v2 and separate bringup nodes are not required.

Mod: com.bxi.upper_body_teleop (provided by HumansX to system users)
PICO client: XRoboToolkit-PICO-1.1.1.apk

Safety: Validate in simulation before using the real robot. Use a gantry or equivalent protection, clear the arm workspace, keep the emergency stop reachable, and begin with slow, small motions.

Installation

Install the Mod in the independent directory that is not overwritten by App updates:

sudo mkdir -p /opt/bxi/mods
sudo git clone <provided-repo-url> /opt/bxi/mods/com.bxi.upper_body_teleop

Update an existing checkout:

cd /opt/bxi/mods/com.bxi.upper_body_teleop
git pull --ff-only

If an older project already contains the same Mod in its built-in mods or private_git_mods, back it up and move it outside the scanned directories. Two copies with the same Mod ID will prevent startup.

Startup

Startup method	Project directory	Handling
Remote controller	`~/bxi_ws/bxi_rl_controller_ros2_example`	Source tree; rebuild the main project after updates. The Mod is loaded from `/opt/bxi/mods`.
App	`/opt/bxi/bxi_rl_controller_ros2_example`	App-downloaded prebuilt tree; no manual build. The Mod is loaded from `/opt/bxi/mods`.

Start the robot and the normal control program. The Mod nodes start automatically when com.bxi.upper_body_teleop/upper_body_teleop is entered. Do not run the legacy elf3_arm_bringup_nohand.launch.py, pico_bxi_server, or bxi_teleop_v2 scripts separately.

PICO Connection and Calibration

Use the same PICO connection and body-tracking calibration procedure as Sonic:

Secure one Motion Tracker to each leg, with the button/indicator side facing upward, and power them on.
Open Motion Tracker on the PICO home screen, confirm both trackers are connected, select Start Calibration, and complete the guided procedure.
Select Adjust Floor and align the virtual floor with the physical floor.
Open XRoboToolkit and connect to the robot through Network → PC Service using the robot's LAN IP.
Confirm these settings:

Section Option Setting

Tracking Head Selected

Tracking Controller Selected

PICO Motion Tracker Mode Full-body

PICO Motion Tracker High-Acc Selected

PICO Motion Tracker Num 2

Data & Control Send Selected
Confirm the Network status is WORKING and the log has no continuous errors. Then enter the Mod state and perform the button calibration.

Section	Option	Setting
Tracking	`Head`	Selected
Tracking	`Controller`	Selected
PICO Motion Tracker	`Mode`	`Full-body`
PICO Motion Tracker	`High-Acc`	Selected
PICO Motion Tracker	`Num`	`2`
Data & Control	`Send`	Selected

Operation

From normal, press LB + LT + X (btn_10=17) on the remote controller to enter upper-body teleoperation.
On PICO, enable Body Tracking, Controller, and Send. Confirm XRoboToolkit reports WORKING.
Hold the standard upright posture and press A+B+X+Y to calibrate. Successful calibration enters POSE automatically; A+X is not required.
Hold the left or right grip to take over the corresponding arm. Releasing the grip smoothly returns that arm to its PD standing posture.
The left and right triggers control the corresponding grippers. Each state entry performs a low-speed gripper limit calibration.
Press A+B+X+Y again to recalibrate; both arms return to PD posture during calibration.
Exit through the standard system event to normal, PD brake, recover, or zero-torque.

A+X no longer toggles following mode. If PICO temporarily disconnects, the lower body continues under the gait policy and both arms hold the PD posture.

Video Streaming

MediaMTX and the head-camera node are managed by the Mod. The default URL is rtsp://<robot-ip>:2212/video. Select this address in the PICO app on the same LAN; no separate video script is required.

Acceptance and Troubleshooting

Logs should show mediamtx_server, head_camera_rtsp, pico_manager, and arm_ik_bridge starting automatically;
A+B+X+Y enters POSE, and the gripped arm follows the controller;
Triggers control the grippers, and child processes stop on state exit.

For a duplicate Mod ID error, keep only /opt/bxi/mods/com.bxi.upper_body_teleop and move the old project copy outside the scanned directories. If no PICO data arrives, wake the headset, enable Body Tracking and Send, and confirm WORKING.