Design and evaluation of a six-component load cell

This paper describes the design process and evaluation results of a compact six-component load cell. We first investigated the strain distributions of a parallel plate structure (PPS) for measuring three components of a force, a moment and a torque. We then designed a double PPS for measuring six components of forces and moments and predicted output strains. We developed a new six-component load cell including a ring-type structure using a PPS as the basic sensing element. In order to minimize coupling errors, we determined the location of strain gauges using finite element analysis and then connected the strain gauges so that bridge circuits with four strain gauges would be balanced. Calibration tests were performed to evaluate sensitivities, coupling errors and nonlinearity errors.