Kinematic and dynamic analyses of general robots by applying the C-B notation-RaMIP (Robot and Mechanism Integrated Program)

In this thesis, a new symbolic representation based on 4x4 homogeneous matrices, C-B (Cylindrical Coordinates - Bryant Angles) notation, has been applied to the kinematic and dynamic analyses of general robots, and a computer algorithm named RaMIP (Robot and Mechanism Integrated Program) has been developed on a Sun workstation for the design and analysis of robots and mechanisms. RaMIP can be used to model most industrial robots currently in use. It performs three-dimensional kinematic and dynamic analyses and takes advantage of the computational efficiency of C-B notation. The C-B notation allows the user to model an arbitrary mechanism consisting of any combination of revolute, prismatic and spherical joints. RaMIP has the capability of presenting results in the form of two- and three-dimensional plots of colored contours, as well as tables of numerical data. The algorithm is examined and tested by analyzing several commercial robots. Kinematic and dynamic results are computed and presented in two- and three-dimensional graphs and compared with known data to probe the validity and accuracy of RaMIP. It should be noticed that the efforts completed in this thesis present only the first step towards the implementation of a general purpose computer algorithm -RaMIP- for the automated design and analysis of open- and closed-chain mechanisms utilizing C-B notation

Control system design for robots used in simulating dynamic force and moment interaction in virtual reality applications

This dissertation presents an approach to simulating the dynamic force and moment interaction between a human and a virtual object using a robotic manipulator as the force transmitter. Accurate control of the linear and angular accelerations of the robot end effector is required in order for the correct forces and moments to be imparted on a human operating in a computer generated virtual environment. A control system has been designed which is robust in terms of stability and performance. This control system is derived from abbreviated linear and nonlinear models of the manipulator dynamics which are efficient enough for real-time implementation yet retain a sufficient level of complexity for accurate calculations. An efficient multiple-input multiple-output (MIMO) pole placement scheme has also been devised which locates the pre-specified system eigenvalues. The controller gains are given as explicit functions of a desired trajectory to be followed and, thus, are time varying such that the overall closed-loop system is rendered time-invariant. Key software elements were automatically derived and output in compiler-ready form demonstrating the feasibility of automatic, computer generated control laws for complex robotic systems. Test results are given for a PUMA 560 used to impart dynamic forces on a user operating in a virtual environment