Application of Mass Cancellation Method for Mechanical Impedance Measurement of Hand-Arm System Under Microgravity Simulation

Mechanical impedance is one of the most important parameters to characterize the biodynamic response of the hand-arm system. However, the mechanical impedance measurement of the hand-arm system may be affected by the measuring equipment. Similar problems exist in the mechanical impedance measurement of the hand-arm system of on-orbit hand-transmitted vibration. A typical mass cancellation method is applied to solve the influence of handle quality on measurement. The mechanical impedance of handle-only and handle-hand-arm system coupling is measured under microgravity simulation and calculated respectively. The results show that the mechanical impedance of the hand-arm system is consistent for different subjects under microgravity simulation. The frequency of the peaks and troughs of the mechanical impedance obtained is similar to the published mechanical impedance standard. Some of the differences in details may be due to the different working conditions of microgravity simulation and ground gravity conditions.