Stress Analysis For Actuating Station Of Laparoscopic Clamp And Research On Interaction With Soft Tissue

Compared with traditionally-developed surgical procedures,minimally invasive surgery has many advantages,and it has gradually become the preferred surgical method for patients.However,in the process of minimally invasive surgery,contacting directly tissue are not possible,resulting in the surgeon lacking accurate tactile perception and position perception,which seriously affects the efficiency and safety of the operation.Moreover,in the process of developing the minimally invasive surgical clamp,the interaction mechanism between the clamp and the biological soft tissue has not been studied,and it has seriously hindered the development of the minimally invasive surgical technology to the direction of intelligence and information.Therefore,this article has researched a tactile feedback on minimally invasive surgical instruments and interactions with soft tissue.This paper constructs the stress model and mathematical model of the clamp execution end.From the simulation of laparoscopic clamping operation and traction action,clamp gripping and traction movement simulation tests were conducted to study the mechanical response characteristics of porcine liver tissue being loaded,and the influence of different traction force and traction velocity on dragging tissues.The main findings are as follows:The stress distribution model of the cross-section of the clamp head in the clamping process was established,and the stress distribution model of the cross-section of the wedge tooth during clamping and gripping was also established.A force transmission model and an angle model in the implementation end of the minimally invasive surgical clamp was established.The mathematical model of the clamp end is simulated by MATLAB software.It is shown that as the axial displacement of the inner shaft of the clamp increases,the angle of the clamp gradually decreases,and the force of the clamp head concentrates.Increase first and then decrease.During the clamping process,as the axial load target value increases,the clamp angle decreases,and the center force of the clamp head increases.During the pulling process,with the increase of preload axial force,The maximum traction force and the maximum axial displacement increase without slippage,the traction force increase with full slip,and the axial displacement decrease.With the increase of the axial movement speed,the number of stick-slip increases,the stick-slip speed and displacement both increase,and the axial displacement value when fully slipping increases.