I disabled the magnetometer on my 3-Space sensor, and now I am seeing a lot of drift in my orientation data. Why is this happening, and what can I do about it?

All gyroscopes inherently have some drift over time. Unfortunately, it is not possible to compensate for this drift without another external reference. In our sensors, we use the magnetometer data to correct for this -- so if the magnetometer is disabled, you may be seeing some drift in orientation due to this. You may want to try calibrating the gyroscope to decrease the amount of drift as much as possible, but we recommend enabling the magnetometer and using gradient descent calibration to compensate for magnetic interference.