title: Core Motion with external sensor data?
body: <p>I have designed a device that transmits motion data over BLE. Is there any way to subclass or otherwise use Core Motion with data that is not derived from the internal iPhone sensors?</p>
  
  <p>I had a look at <a href="https://github.com/orbotix/Sphero-iOS-SDK/tree/master/samples/SphereMotionTeapot" rel="nofollow">https://github.com/orbotix/Sphero-iOS-SDK/tree/master/samples/SphereMotionTeapot</a> </p>
  
  <blockquote>
    <p>"Device-motion data is derived from both the accelerometer and the
    gyroscope [apparently these are in the Sphero]; Core Motion processes the data before delivering it to the
    application."</p>
  </blockquote>
  
  <p>i.e. they appear to be introducing external sensor data into Core Motion, but I am not smart enough to figure out how they are doing it.</p>
  
  <p>I have BLE delegates set up to receive and present the acceleromoter, gyro and magnetometer data but can I get this into Core Motion to run it's fusion algorithms and device motion updates using this data?</p>
  
  <p>Any pointers to how this might be achieved would be very useful and I will post back with any success stories.</p>