基于电流信号估计抓握力的假肢手抓握控制

Grasp force control of prosthetic hands based on force estimation using motor current signals

为避免假肢手需外置力传感器进行抓握力控制的不足,提出了一种通过电流信号估计抓握力的假肢手抓握力控制方法。根据假肢手模型、接触力模型和直流(DC)电机模型建立基于电流信号的假肢手抓握力估计模型,将抓握力估计模型与比例—积分—微分(PID)控制器结合,在无需外置力传感器的情况下对假肢手进行抓握力控制。抓握控制仿真和实验表明:所提出的假肢手抓握力估计方法和控制方法有效。

Aiming at the shortcomings of three-axis geomagnetic sensor such as troublesome steps of traditional error compensation method,relying on external instruments,so it can not be applied to geomagnetic navigation system of vehicles,an online compensation method for three-axis geomagnetic sensor error based on unscented Kalman filtering is proposed. Generation mechanism of geomagnetic sensor error is analyzed,and geomagnetic sensor error model suitable for vehicle navigation system is obtained. Unscented Kalman filter is designed to complete the estimation of the unknown parameters in the model,thus realize on-line compensation of error. The experimental result shows that the proposed method is effective and feasible,and the precision after compensation is within 0. 5°,which can achieve better compensation effect.