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Experimental. xArm 7 support is new and has not run on many benches yet. Commands and setup may change without notice. Expect rough edges, stay at the e-stop, and tell us how it goes at team@dreamscalelabs.com. There is no shared model for xArm 7s: you run your own deployment, fine-tuned on demos recorded on your bench.

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What you need

  • Two UFACTORY xArm 7 arms, called aft and fore, each with an xArm Gripper (G2 or G1) or no gripper.
  • Three RGB cameras: top, looking down at the bench, left on the fore arm’s wrist and right on the aft arm’s wrist. RealSense D435s work, as do USB (UVC) cameras.
  • A Linux computer on both control boxes’ Ethernet network, wired to the cameras.
  • The e-stop within reach.

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1. Install and set up the rig

Enter each arm’s control box address and gripper, then assign the three cameras. Setup saves a preview from each camera so you can tell them apart, and sets them to 640x360. It only reads the arms and grippers; nothing moves. A camera another program holds (a recorder, a teleop stack) is listed without a preview and can still be assigned. Setup writes ~/.config/dreamscale/xarm7.json. You can also write it yourself, for example from a coding agent:
  • gripper: g2, g1 or none.
  • gripper_control: position moves the jaw to the commanded fraction of its travel; threshold shuts it at 0.5 or more and opens it below.
  • roles: top is the scene camera, left the fore arm’s wrist, right the aft arm’s wrist, each naming a camera’s id.
  • cameras: a RealSense is realsense:<serial> with physical_id usb:8086:<serial>; a USB camera is its /dev/v4l/by-id/… path, as both id and device, with physical_id usb:<vendor>:<serial>. When in doubt, run setup once and copy what it saved.

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2. Check everything

It reads both arms, both grippers and the three cameras without moving anything, and checks that your deployment is ready to run here. Every line shows a ✓. Clear any controller error in UFACTORY Studio first.

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3. Save a home pose

Move both arms in UFACTORY Studio’s manual mode to where every run should start, grippers clear of the bench and the wrist cameras on the work area. Then:
dreamscale robots xarm7 home moves both arms back there slowly and opens the grippers.

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4. Your deployment

Your demos need, in this order:
  • observation.images.top, observation.images.left and observation.images.right;
  • observation.state: 16 values, the aft arm first. Each arm has seven joint positions in radians, then its gripper’s angle from 0 (open) to 0.85 radians (closed);
  • action: the same 16 values, with each gripper as a close command from 0 (open) to 1 (closed).
Deploy the fine-tuned model as on Deployments. The deployment’s cameras must be those three keys in that order, with 16 state and action values.

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5. Run it

The arms will move. Clear the bench and keep the e-stop within reach. Software limits do not prevent collisions, and cloud inference does not replace your robot’s safety configuration.
  1. At Instruction, type a task.
  2. At Enter to start, press Enter. Both arms enable at their current pose.
  3. The arms run the task. Press Ctrl+C to stop; they return home if you saved a home pose, and you’re asked for the next instruction.
Joints move at most 0.5 rad/s, and a command may lead the measured position by at most 0.2 rad. Each gripper moves to the commanded fraction of its travel (or, with gripper_control set to threshold, shuts at 0.5). A held gripper keeps its last command, so a gripper closed on an object stays closed.

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Your own control loop

If your model is prompted one step at a time, or one arm should hold still while the other works, drive the arms from Python. This example steps through a list of instructions, Enter for the next, and holds the arm each instruction doesn’t move:
Its source is a starting point for your own runner. It calls policy.next_action(), which handles real-time chunking for you; a loop that plays whole chunks from policy.predict() passes the actions still to play as committed_actions (see Running chunks on your own clock). Stuck? See Troubleshooting.