基于动力学模型的手术器械夹持力估计研究

Study on Estimation of the Gripping Force of Surgical Instruments Based on the Dynamic Model

手术器械夹持力估计问题一直是微创手术机器人手术器械研究的重点。在微创手术过程中,夹持力过大会造成组织损伤,夹持力过小会使缝合针等脱落,引发危险。因此,研究如何估计手术器械夹持力是非常有必要的。根据手术器械的结构特点,提出了一种基于动力学模型的夹持力估计方法。建立的模型考虑了手术器械动力学模型、丝传动系统力和位移传递特性和直流电动机特性,得到了手术器械电动机电流和夹持力之间的关系;通过Matlab对夹持力模型进行仿真验证,得到了手术器械末端执行器随电动机电流变化的夹持力变化曲线。仿真结果表明,基于动力学模型的手术器械夹持力估计模型与实际情况相符,为后续的手术器械夹持力安全保障研究提供了理论依据。

The problem of estimating the gripping force of surgical instruments has been the focus of re-search on minimally invasive surgical robotic surgical instruments.During the minimally invasive surgery,exces-sive gripping force can cause tissue damage,and too small gripping force can make suture needles fall off and cause danger.Therefore,it is necessary to study how to estimate the gripping force of surgical instruments.Ac-cording to the structural characteristics of surgical instruments,a method for estimating gripping force based on dynamic model is proposed.The dynamic model of the surgical instrument,the force and displacement transmis-sion characteristics of the cable driven system and the direct-current motor characteristics are considered in the established model,and the relation between the surgical instrument motor current and the gripping force is ob-tained.The gripping force model is validated by using Matlab simulation,and the gripping force variation curve of the surgical instrument end-effector with the change of the motor current are obtained.The simulation results show that the gripping force estimation model of the surgical instrument based on the dynamic model is consis-tent with the actual situation,which provides a theoretical basis for the subsequent research on the gripping force security of the surgical instrument.