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CogSimGuy's avatar
CogSimGuy
Protege
11 years ago

Sensor Orientation Request

Is there any chance of having the SDK capable of providing the HMD orientation in other reference frames? Any of the following would be helpful for integration into "non-sitting and playing video games" type applications! :shock: All these new 'modes' would be post filtering/smoothing...

- untared orientation
- tared against a user supplied quat
- reference frame tared (i.e. gravity down from accelerometers and mag north from compass)

2 Replies

  • kojack's avatar
    kojack
    MVP
    11 years ago
    It's basically just a matter of multiplying the inverse of the desired reference frame by the current sensor quaternion.
    So for example (depending on your math library, language and engine) the middle one (user supplied quaternion) would be:
    orientation = userquaternion.Inverse() * oculusOrientation;

    No idea what untared or tared means (the net says weighed, which doesn't really match this use).
  • CogSimGuy's avatar
    CogSimGuy
    Protege
    11 years ago
    Yes thanks, that's basically the 'work around' that I'm using now. Tared is a quaternion (or any reference) based on a given orientation. This is what you get when you fire up the Oculus or reset it, you get an orientation based against a reference system (ie. the HMD orientation at start up or reset). The actual 9 axis AHRS system inside measures against the real world position on the surface of the earth and then does an inverse multiply (after filtering/smoothing) to give you what you get back as an orientation based against the start up or reset world reference. What I would like to get is the actual world reference orientation or reference frame based orientation ( that's based on gravity vector down, magnetic north forward ). These are two modes that are normally available on other commercial AHRS systems and as we are looking to integrate the Oculus with those type systems it would be very beneficial to have those modes available. In this manor we could keep the Oculus sync'd in orientation with this other system (using real world orientation) without having to 'tare' one to the other...