The main purpose of this thesis is to plan a active-charactered testing system on treadmill. The main core of the system is DSP MCU, and works with torque sensor, measurement board, and PC. Under mapping out mechanical hardware, electrical hardware and firmware, the system measures voltages, currents, torque and rotate speed from AC server motor and saves as digital form in DSP MCU. After measuring, the data are calculated through FIR filter, and calculate different characters. The system calculates power with voltages and currents, and identify the parameters of powers. Besides the power, system also calculates the mechanical power with torque and rotate speed. Finally the system can get the total efficiency of the treadmill.