Software Development In Kinematics Simulation Of The 5-dof Manipulator

Compared with the 6-dof manipulator, the 5-dof manipulator has those advantages of simplied structure, low in its design and production cost. In the meantime the 5-dof manipulator is qualified for the most of applicatoins which the 6-dof manipulator has, such as welding and spray-painting. One of the key factors to apply the manipulator efficiently is virtual reality technology, which display the movement of manipulator after trajectory planning. In practice, simulation softwares for 6-dof are more mature than softwares for 5-dof,so the simulation software for 5-dof has its research value.The 5-dof manipulator which designed and made by our lab is the research object of this paper. Combined with virtual reality technology and VC++ platform, the robot simulation system has implemented with functions of robotics kinematics simulation, robot trajectory planning and the manipulator joint control, etc. The robot simulation system had completed those established tasks and performed very well. Combined research purposes, the main contents of this paper have been listed.1) The kinematics models for the 5-dof manipulator have been made by using the D-H method,which described the transformation matrixes for each joint coordinate. Forward kinematics have been solved by multiplying those transformation matrixes. On the basis of analysis the difficulties in the inverse kinematics, the solution method for the inverse kinematics have been proposed.2) By using the Object-oriented modeling method of UML the integral analysis of the robot simulation system has been made. Some use cases have been summarized form the requirement analysis of the simulation software, including simulation display of 3D manipulator models, robot trajectory planning, manipulator joint control and kinematics modeling, and then we obtained those main function modules of the system. Based on the functional requirements, we have achived those input-output volumes, which helped us to design the software interface.3) The manipulator 3D models have been rendered in the virtual scene based on the OpenGL application framework, by the way of importing the 3D joint models. We have also introduced thet implementation process about the manipulator trajectory planning and the communication in the robot joint controling.4) The trajectory planning for the 5-dof manipulator has been conducted in Cartesian coordinate, which including interpolation algorithm for linear path and arc path.