Surface gripper can't use & isaacsim twinkle

Omniverse Isaac Sim
1

6.0.0
5.1.0
5.0.0
4.5.0
4.2.0
4.1.0
4.0.0
4.5.0
2023.1.1
2023.1.0-hotfix.1
Other (please specify):

Operating System

Ubuntu 24.04
Ubuntu 22.04
Ubuntu 20.04
Windows 11
Windows 10
Other (please specify):

Isaacsim twinkle issue:

I have already installed the 580.88 driver on my Windows, but unfortunately my IsaacSim 5.1 display still flickers at a high frequency.

surface gripper issue:

Today I added a linear axis and a rotational axis to the gantry, and I also added a D6 joint to the head. I configured the drive, attachment API, etc.

After that, I used the surface gripper controller to perform suction.

However, an issue occurs where the gripper repeatedly switches between attach and detach states (and in some cases cannot grip at all).

This picture is repeatedly switches between attach and detach states:

It cause my cube move up and down.

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image543×156 7 KB

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image567×143 22.9 KB

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image536×590 24.6 KB

This picture is cannot grip at all setting :

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image506×431 16.8 KB

In this situation, how should I correctly assign Body 0 and Body 1 for the D6 joint?

Also, is there any part that might not have been properly configured or added?

Thank you.

3

Hi, for the Surface Gripper issue:
For your D6 attachment joint, here are the requirements the Surface Gripper Manager expects (see the
Surface Gripper Extension Doc:

  • Body 0 must be the gripper-side rigid body (the D6 head mounted to your gantry). All attachment joints under the same gripper must share the same Body 0.
  • Body 1 should be left empty in the USD authoring. The manager dynamically assigns the target rigid body at runtime when the raycast detects a valid object to grip.
  • The joint must have Exclude From Articulation set to True (the manager will force this at runtime, but setting it explicitly avoids a first-frame hiccup).
  • The joint must be enabled.

The repeated attach/detach behavior (the cube bouncing up and down) is almost always one of these:

  1. Missing ClearanceOffset — the raycast origin is inside the gripper’s own collider, so it alternates between hitting itself and the target. Select the D6 joint, add the AttachmentPointAPI schema (Properties panel → + Add → Edit API Schema → search AttachmentPointAPI), and set ClearanceOffset to a value just beyond the gripper body’s surface (e.g. 0.01–0.05 m depending on your units).
  2. Wrong Forward Axis — defaults to X. Make sure this matches the joint’s local axis that points toward the cube.
  3. Shear Force Limit / Coaxial Force Limit too low — the constraint forms, instantly exceeds the limit, breaks, and the manager immediately retries. Try increasing both by 10×–100× as a sanity check.
  4. Max Grip Distance too small — if the raycast never finds the cube, the gripper never attaches; if it’s only barely in range, small contact jitter can cause cycling.

I’d suggest loading the shipped example (Window → Examples → Robotics Examples → Manipulation → Surface Gripper) and comparing its D6 joint configuration against yours — that example uses exactly the gantry + D6 pattern you described and is a known-good reference.