Forum Discussion

🚨 This forum is archived and read-only. To submit a forum post, please visit our new Developer Forum. 🚨
vallenkilling's avatar
vallenkilling
Honored Guest
1 year ago

How To Get Contoller Veclocity (Meta SDK All-In-One)

I'm trying to get the velocity of how to get either of the VR Controllers so that it can be applied to another object when hit. I cant figure out how to aquire the velocty with the SDK setup. Any help please?

3 Replies

Replies have been turned off for this discussion
  • hvox1138's avatar
    hvox1138
    Protege
    1 year ago

    Hi vallenkilling,

    I don't think there's a centralized place from which that value is provided, but there are tools available that will help you calculate it. For a simple calculation, you can just monitor displacement over time directly --- for example, `(controllerPositionNow - controllerPositionATenthOfASecondAgo) / 0.1 seconds`.

    If you want something more sophisticated, take a look at RANSACVelocity.cs (in the essentials package > Runtime > Scripts > Throw). This is how ISDK itself calculates velocities for throwing --- you can see this usage in Grabbable.cs --- but it should be usable for calculating good, noise-resilient velocity estimates of other things too, including controllers. I don't think there's much documentation about that file yet, but if you're interested and have questions, either I or LucaMefisto should be able to help you dig deeper.

    Hope this helps, and best of luck!

  • LucaMefisto's avatar
    LucaMefisto
    Meta Employee
    1 year ago

    Hi  vallenkilling, 

    Getting the  velocity of a VR Controller can be done in different ways. You can directly query it in OVRInput using (note that it is local to the tracking space):
    `OVRInput.GetLocalControllerVelocity`.

    Alternatively, if you want to do it without OVR  and filter out possible noisy data you can use the InteractionSDK RANSACVelocity.cs class. You will have to create a component that makes use of it and attach it to a Controller thought.

    Roughly speaking:

    ```

    public class ControllerVelocity : MonoBehaviour
    {
        //create the velocity calculator with a small memory to store
        //the last few pose samples
        RANSACVelocity _velocityCalculator = new RANSACVelocity(10, 2);
        private void OnEnable()
        {
            //reset the calculation everytime you enable the component
            _velocityCalculator.Initialize();
        }
     
        private void Update()
        {
            //feed a timed pose every frame.
            //Assuming this component was parented with the controller transform
            _velocityCalculator.Process(this.transform.GetPose(), Time.time, true);
        }
     
        public Vector3 GetVelocity()
        {
            //Call this to get the filtered velocity of the controller
            _velocityCalculator.GetVelocities(out Vector3 velocity, out Vector3 torque);
            return velocity;
        }
    }
    ```




  • Iseldiera's avatar
    Iseldiera
    Protege
    1 year ago
    Luca's answer has what you need, but in case you need the angular velocity here is some additional info:
     
    // Get the velocity of the left controller
    Vector3 leftControllerVelocity = OVRInput.GetLocalControllerVelocity(OVRInput.Controller.LTouch);
     
    // Get the velocity of the right controller
    Vector3 rightControllerVelocity = OVRInput.GetLocalControllerVelocity(OVRInput.Controller.RTouch);
     
    // Get the angular velocity of the left controller
    Vector3 leftControllerAngularVelocity = OVRInput.GetLocalControllerAngularVelocity(OVRInput.Controller.LTouch);
     
    // Get the angular velocity of the right controller
    Vector3 rightControllerAngularVelocity = OVRInput.GetLocalControllerAngularVelocity(OVRInput.Controller.RTouch);