Design of a novel regionalized platform for measuring plantar multi-axis force

When the human body is balanced, measuring shear force and pressure of foot is challenging due to significant differences. To address this, a regional plantar multi-axis force measurement platform was developed. The platform divided the foot into three areas to measure shear force, pressure, and position, and used balls to support big plantar pressure. Mathematical models for the sensor elastic elements were created based on material mechanics and Timoshenko beam theory, with verification through finite element method simulations. Finally, the principle of device was verified by static loading experiments. The results indicated a linear relationship between applied forces and output strain. The position error, pressure error and shear force error between the theoretical values and simulated values were 5%, 3.64% and 4.85% respectively, which proved the correctness of the theoretical models. The errors between simulation and experiment are less than 10%. The coupling errors of shear force were about 2.35%, and the coupling errors of pressure were a maximum of 1.5% in experiment. Therefore, the platform can be used to measure three-axis plantar force and the position, and can realize the measurement of small shear force under large pressure.