Gripper connection and serial numbers

The gripper is the same on both editions; only where the cable goes and how detection is checked are split into "Backpack Kit / Developer Kit" tabs.

• Backpack Kit buttons, LEDs and voice: Gripper buttons, LEDs and voice.
• Product positioning and components: XTac UMI G1; specs: Technical specifications.

Leader gripper connection and use

Left leader gripperRight leader gripper

The leader gripper takes power and communication over USB Type-C.

Before connecting

• Left and right leader grippers, two USB locking cables, and the collection unit (the backpack or the collection PC; for the collection PC see Collection PC requirements).
• No 9V/12V fast-charging adapter connected directly to the leader gripper.
• Type-C locking end intact, nothing foreign in the port.
• Visuotactile sensor surfaces free of dirt, scratches, looseness and foreign objects.

Connection steps

1. Take out the USB Type-C communication cable.
2. Plug it into the leader gripper body's Type-C port and tighten the locking screws.
3. Plug the other end into the collection unit: Backpack Kit left gripper to UMI-L, right to UMI-R; Developer Kit to a Type-C or Type-A port on the collection PC.

Power-on and detection

Backpack KitDeveloper Kit

• LED solid green (standby).
• The "cameras" counter at the console's top right shows all cameras online, 6 on the gripper side (2 wrist cameras + 4 visuotactile).
• The "Live monitor" page shows both fisheye views and all four tactile views.
• Offline cameras are marked "(offline)" on the System → Device info page.

Check the UVC device count with lsusb: 6 for bimanual (2 wrist cameras + 4 visuotactile sensors), 3 for a single gripper.

lsusb

Each red box is one leader gripper:

Text in the box	What it is	Per leader gripper
Xense Robotics ... GSPS01…	Visuotactile sensor	2
Sunplus ... XCA…	Wrist fisheye camera	1

• Telling sides: by the serial number's last digit (odd-left / even-right, see Serial numbers and side identification); in the picture …0069/…0071 are left, …0070/…0072 right.
• Wrong count: check cable locking and USB contact; if still wrong, see Hardware faults.

A leader gripper needs travel calibration for a normalized opening:

• Backpack Kit: console System → Gripper page (write zero closed → write maximum travel fully open).
• Developer Kit: see Gripper calibration (zero + travel); the software refuses to connect to an uncalibrated leader gripper, and both sides of a pair must be calibrated.
• Firmware, SDK and repository versions must match; see You must upgrade to the latest versions.

Follower gripper mounting and connection

The follower gripper mounts on the robot's end effector and is not side-specific; mind flange orientation, cable routing and workspace.

Before mounting

• The robot is stopped and in a safe pose.
• Flange size, screw spec, mounting orientation and end-effector payload meet the project requirements.
• 24V adapter, Type-C communication cable and locking parts intact.
• Cables routed clear of joints, the gripper's range of motion and obstacles.

Flange mounting

Flange mountingFlange dimensions

Adapter hole pattern, mounting frame and gripper models (URDF / MJCF / USD) are in XTac-UMI-Description.

Power and communication connection

1. Take out the USB Type-C communication cable and the 24V power adapter.
2. Connect the 24V power adapter to the gripper body.
3. Plug the screw end of the Type-C locking cable into the body and tighten the locking screws.
4. Plug the other end into the collection unit and confirm communication in the software.

Cable and mounting check

• Gripper firmly fixed, 24V secure, Type-C locked with enough slack.
• Cables cannot be pulled, bent or tangled during motion.
• First run at low speed to confirm nothing interferes.

Power and connection requirements

Item	Leader gripper	Follower gripper
Power	USB Type-C bus power, DC 5V/500mA, no separate supply needed	24V power adapter (do not use a supply with the wrong rating or a faulty one); Type-C is communication only
Cables	Supplied locking cable: Type-C on the gripper end, Type-C or Type-A on the other	Type-C communication cable + 24V power cable
Connect and lock order	Connect the gripper end and tighten the locking screws first, then the collection unit	Connect 24V power first, then Type-C, and tighten the locking screws
Disconnect order	Unplug the collection unit end first, then loosen the screws and unplug the gripper end	Unplug the collection unit end first, then cut 24V, and finally loosen the screws and unplug the gripper-end Type-C
Static	Anti-static precautions when powering on/off and removing or fitting sensors	Same as leader

• Before unplugging, stop collection, recording, robot motion and replay.
• Whole-system power order: Backpack Kit Connection and disconnection order, Developer Kit Power-on and power-off order.
• On an unexpected reboot or no detection, stop immediately; see Hardware faults.

Serial numbers and side identification

Last digit of the serial's running number: odd = left, even = right.

• Applies to grippers, visuotactile sensors, wrist cameras and Pico trackers.
• Developer Kit: the collection software assigns sides automatically (see Device auto-discovery and the odd-left/even-right rule); to check by hand, run lsusb and read the last digit.
• Backpack Kit: the console's System → Device info page shows each gripper's left / right badge and SN.

Safety notes

Power, the ban on direct fast charging, plugging, static and sensor-surface requirements: Safety and compliance.

• Sensor cleaning, storage and removal/refitting: Maintenance.
• Run the follower's self-check before letting it move.
• Once detected, run a first collection with the Backpack Kit quickstart or the Developer Kit quickstart.