Dynamic analysis algorithm for a micro-robot for surgical applications

The applications of robotics in medical field have increased extensively in the last two decades. The purpose of this paper is to present an algorithm for a complete dynamic analysis for a six degrees of freedom micro-robot intended for surgical applications. The algorithm consists of five modules and it can easily draw the torque history for each joint provided that the homogeneous transformation matrices and the robot and joint parameters are known. The kinematic equations of motion were obtained using Denavit–Hartenberg notations. The workspace of the robot can be drawn through the solution of the inverse kinematic equations considering the physical limit of each joint. The trajectory planning was derived in the joint space using two different techniques; fifth-order polynomial, and soft motion trajectory. The dynamic equations of motion were derived using the Lagrangian–Euler technique which is appropriate for numerical simulation. The standard inverse dynamics computation method was used to calculate the required hub torque, to move each joint according to a prescribed trajectory. A simulation analysis was carried out to choose the most suitable method that gives the smooth torque profile its best performance for the robot under investigation.The simulation results were obtained using MATLAB Symbolic Toolbox.