Abstract: A multi-posture stride length calibration system for indoor positioning includes: at least an inertial measurement unit, configured to sense at least a signal; a signal preprocessing unit, connected to the inertial measurement unit to process sensed signal; a multi-posture determination unit, configured to determine at least a posture based on processed signal; a step-computing decision unit, configured to compute a number of steps and a step frequency based on processed signal; a map feature calibration unit, configured to receive the number of steps, step frequency and posture to determined a stride length and decide whether the stride length matching a criterion; a step-computing threshold adjustment unit, configured to adjust a step-computing threshold if stride length not matching the criterion; and a stride length regression unit, configured to update a stride length regression curve for posture based on step frequency and stride length if stride length matching the criterion.

Abstract: An exercise learning system including a sensing unit and a processing module is disclosed. The sensing unit includes at least one sensor used for being disposed on the body of a user. Each sensor further outputs a sensing data according to the exercise state of the user. The processing module generates at least one critical action data of the user according to the at least one sensing data. The processing module further synchronizes and compares the at least one critical action data with the corresponding at least one pre-produced action data.