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XR Grab Intractable Detection Inconsistent with XR Direct Interaction and QCHT hands

We're struggling to get consistent grabs or pinches from our player. We're receiving the hand input as an action type of "button". 

Our XR grab interactable is below (everything cropped from the screenshot is at its default setting). We've got a simple capsule collider for our handle, but grabs often aren't detected.


We've tried moving the attach and grab transforms, and changing position and size of collider volume, but it seems like you often need to "grab and regrab" to get the grabs detected.

An APK of our experience is here, if that would help with debugging.

Please let us know if there's anything else we should be trying or could provide in the meantime to help, or if there's a forum dedicated to the QCHT package we should post this on instead.


I just tested the apk on A3 and realized that when grabbing the door at the bottom instead of the handle where the visualization indicates to grab, it works every time. It looks to me like the colliders are off. 

  • Are you using VRX or A3? 
  • Could you share a screenshot of:
    • Your scene & prefab setup with visible colliders please? (Perhaps the prefab is overridden in the scene?) 
    • The capsule collider settings
  • What version of the Spaces SDK are you using? 

About your XR Interactable Setup:

Our QCHT samples have a different default setup - look at the QCHT Sample - Proximal scene and the ProximalCube object to see the recommended setup. 

(Side note - the game looks really good; I like the concept!)

The prefab set up is attached below (we've verified if the prefab is being overridden, it is not).

We can look at more closely replicating the settings for the ProximalCube. The capsule collider shown is added under our "Colliders" list. As you can see, the transform for the door is at the bottom. We also have the AttachTransform, which we've attempted as an override (the AttachTransform is closer to where we intend the handle to be).

It looks like only the actual transform for the door is being considered as a valid grab point.



Sorry for the delayed response,

The door itself has a collider as well and I'm assuming that the "Attach Transform" might be overridden by something. 

Is the XR Interactable attached to the door or the door handle? Could you try directly attaching the XR grab interactable to the door handle (Attach Transform) in other words the same object that also has the collider? Would also consider removing the "Attach Transform" reference. 

Could you provide a sample (It does not need to be your assets, just cubes and colliders is fine) to reproduce this bug? I'd like to verify and open a ticket with our engineering team.


I will look into re-arranging the object so the handle is the root. It's a bit inconvenient to do that given the current hierarchy.

This might be more of an XR Interaction Toolkit problem than a problem with the current plugin. However, I would assume the setup shown would at least receive some grab input on the handle.

I've attached a package containing the prefab that is identical to the one shown, with the custom door grab logic we use for our character and for sound stripped.

The bigger issue that seemingly is a part of the plugin is lack of consistent grab detection even when grabbing the "door". It seems like the root is the only thing considered, rather than the volume or collider on the door itself. This is not ideal as the root is at the bottom.

A secondary concern would be lack of control over what sensitivity of motion is needed to register as a grab. If there is some sort of confidence threshold for when a select gesture is registered, it would be helpful for our demo to be able to directly use that instead, so we can trigger a grab with greater consistency.

Let me know if there are any other suggestions. I will update if re-arranging the transforms seems to work as a solution.

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