Patent ID: 8092398

Claim:
A vestibular prosthesis comprising: a wearable motion sensing system including accelerometers and gyroscopes, the motion sensing system is configured to generate motion signals indicative of a motion thereof, wherein the motion includes rotation about two distinct axes; a signal processor in communication with the motion sensing system, the signal processor being configured to generate a first estimate of a tilt of the motion sensing system based on a nonlinear relationship between output from the accelerometers and quaternions that transform a direction of a gravity vector into a body frame of reference that is stationary with respect to the motion sensing system, to generate a second estimate of the tilt based on output from the gyroscopes, to generate a third estimate of the tilt based on the first estimate and the second estimate, and to represent the first, second, and third estimates as quaternions; an actuator configured to be triggered responsive to the third estimate of the tilt being in a predetermined region of a decision space having a first dimension representing a value of the tilt and a second dimension representing a rate of change of the tilt.