Design and preliminary evaluation of a low-cost three-dimensional biomechanical force plate

Abstract Objective: The three-dimensional (3D) force plate is a widely used device in biomechanical research, capable of measuring the ground reaction force (GRF) exerted on the sole of the foot. The forces of human joints are calculated by combining GRF with motion capture data. In the field of nursing and rehabilitation, evaluation of joint pressure can inform further therapy. However, its high cost often limits its application to a small population. Therefore, we aimed to design and manufacture a low-cost 3D force plate to address this issue, which will advance the evaluation of joint pressure in nursing practices. Methods: Through mechanical derivation and finite element method simulation, the feasibility of this 3D force plate was tested. We proposed a method based on simulation results to assist in calibration. Furthermore, we collected the GRF data of the author using the 3D force plate designed in this study. Then we imported this GRF data and the data obtained from motion capture into OpenSim. Results: The 3D force plate consisted of two 3D force sensors and a 600 × 300 mm board. The 3D force plate could measure the 3D reaction force between the sole of a subject’s foot and the ground. The 3D force plate was validated the usability in this study through theoretical calculation and a complete musculoskeletal analysis process. Conclusion: We have completed the design and practicality verification of this low-cost 3D force plate and provided a calibration method based on finite element method simulation assistance. Low-cost 3D force plates can accelerate the popularization and application of musculoskeletal analysis in the field of nursing and rehabilitation, which is helpful for precision health.