The Research On Kinematics And Dynamics Of Six Degree Of Freedom Reconfigurable Modular Robot

Since the first industrial robot was born in 1958, the industrial robot has become an integral part of advanced manufacturing equipment in industrial production. Due to the disadvantages of traditional industrial robots, such as single function, poor environmental adaptation ability, not according to actual production task to generate the best configuration have been unable to meet the demand of diversification of production in the process of production. Reconfigurable modular industrial robot is a kind of modular design method, which can change the configuration of robot according to the different task requirements. Reconfigurable modular robot can not only generate configuration according to the practical demand of production and reduce the production cost, but also greatly decrease the cost during the process of the robot design cycle, maintenance and installation. In this paper, we focus on the 6-DOF-configuration reconfigurable modular robot including the kinematics of the robot, the space trajectory generation, the smooth transfer of trajectory and velocity planning, the construction of simulation platform based on QT, and the derivation of robot dynamics.First of all, we established the robot connecting rod coordinate with D-H method, derived the D-H parameters of the robot and obtained the forward kinematics and inverse kinematics calculation formula.Secondly, the research be conducted on the trajectory generation of 6-DOF-configuration reconfigurable modular robot, and derived the basic algorithm of space trajectory generation including line, cycle and parabola. We can calculate the robot-end-effector's position and gesture matrix at the end of the interpolation cycle time, invoking the robot inverse kinematics program to obtain the angle of each joint based on the given beginning point, target point and intermediate point. The algorithm can then be verified by the mapping of the robot-end-effector trajectory through the robot motion on the simulation platform.Thirdly, attention be paid on the smooth transfer of the 6-DOF-configuration reconfigurable modular robot trajectory. PL transfer method was proposed to reduce the effect of the sharp angle of trajectory transfer on the transfer speed and the stability of the robot continuous path motion. Analysis will be placed on the three basic trajectory transfer, then the calculation formula of PL-arc will be conducted, eventually, PL method implementation process in system will be achieved. S-shape acceleration/deceleration method would be proposed to solve the negative effect caused by the acceleration mutation during the robot start-stop phase on the stability of robot motion. We can yield the speed and displacement calculation formula, give the determination methods of the actual speed section number and verify the algorithm through the simulation platform.Finally, research be landed on the 6-DOF-configuration reconfigurable modular robot dynamics. By the utilization of Lagrange method, we have established the robot dynamics model, derived the joint torque calculation formula, and wrote dynamics program. Compare the simulation data from ADAMS with program output result to verify the correctness of the algorithm.