Description |
Motion capture has applications in many fields. A need has arisen for motion capture systems that are low-cost, mobile, and intuitive. An attitude heading reference system (AHRS) calculates the global orientation of a rigid body by synthesizing the output from an array of sensors. A complete motion capture system utilizing gyroscopes, accelerometers, and magnetometers attached to the main body segments of a human is proposed. This is accomplished by providind a low-cost calibration procedure for micro electro-mechanical system (MEMS) gyroscopes, accelerometers, and magnetometers in order to create a custom AHRS unit. The accuracy of reproducing global orientations using these AHRS units is analyzed for individual modules as well as redundant groups of AHRS nodes for increased accuracy. In order to make the system intuitive, a localization procedure for finding the locations of all AHRS units attached to the body is proposed. Sensors were successfully calibrated to an accuracy sufficient for AHRS development. The accuracy of the AHRS units was verified and led to a functioning motion capture system. The localization procedure was verified with volunteer subjects and successfully finds the location of all attached AHRS units. |