Internal Redundancy – the Way to Improve Robot Dynamics and Control Performances
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The research follows the concept of variable geometry. The concept was originally introduced for general mechanical system in order to improve its dynamic behaviour . Here, we apply the concept to robots. It can be shown that enhancement of robot dynamic performances is achieved. In this paper variation of geometry is considered equally as the motion in robot joints. Thus, a new set of degrees of freedom is introduced. This leads to redundancy – different internal motions are possible for the given external motion of the end-effector. However, there is an important difference from the usual notion of redundancy. Here, the additional joints do not influence the external motion and accordingly cannot improve the end-effector ability for maneuvering. For this reason the new notion is defined the internal redundancy.
Although variation of geometry is treated equally with the motion in robot joints, there is still a difference in the aim of these new degrees of freedom. They should contribute to overcoming the limits of robot actuators, achieving better static compensation, etc. One might say that internal redundancy improves the robot dynamic capabilities. In this paper the mathematical formulation of kinematics and dynamics of robots with internal redundancy is carried out. A case study is presented in order to support the main idea.
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- 1.Egeland, O.: Task-space tracking with redundant manipulators, IEEE J Robotics Automat. 3(5) (1987), 471–475.Google Scholar
- 2.Hedrick, J. H.: Railway vehicle active suspension, Vehicle System Dynamics 10 (1981), 276–283.Google Scholar
- 3.Hogan, N., Sharon, A., and Hardt, E. D.: High bandwidth force regulation using a macro/micro manipulator system, in: Proc. of IEEE Internat. Conf. on Robotics and Automation, 1988, pp. 126–132.Google Scholar
- 4.Nof, S.: Handbook of Industrial Robotics, Wiley, New York, 1985.Google Scholar
- 5.Nakamura, Y.: Advanced Robotics: Redundancy and Optimization, Addison-Wesley, Reading, MA, 1991.Google Scholar
- 6.Meirovitch, L. and Gosh, D.: Control of flutter in bridges, J. Engineering Mechanics 113 (1987), 720–734.Google Scholar
- 7.Potkonjak, V.: Thermal analysis and dynamic capabilities of D.C. motors in industrial robotic systems, Internat. J. Robotics Computer-Integrated Manufacturing 5(2/3) (1989), 137–143.Google Scholar
- 8.Potkonjak, V., Djordjević, G., Milosavljević, Č., and Antić, D.: Design of tactical and executive level of redundant robot control via distributed positioning, Internat. J. Robotics Automat. 11 (1996), 102–110.Google Scholar
- 9.Potkonjak, V. and Krstulović, A.: Modelling of a redundant antrophomorphic arm (Part 1), Simulation of a redundant anthropomorphic arm (Part 2), Robotics and Autonomous Systems 9 (1992), 165–179.Google Scholar
- 10.Vukobratović, M. and Kirćanski, M.: A dynamic approach to nominal trajectory synthesis of redundant manipulators, IEEE Trans. Systems Man Cybernet. 14(4) (1984).Google Scholar
- 11.Vukobratović, M. and Potkonjak, V.: Dynamics of Manipulation Robots, Springer, Berlin, 1982.Google Scholar
- 12.Vukobratović, M. and Potkonjak, V.: Applied Dynamics and CAD of Manipulation Robots, Springer, Berlin, 1985.Google Scholar
- 13.Vukobratović, M. and Potkonjak, V.: Modelling and control of robotized systems with variable geometry, Part 1: General approach and its application, Part 2: Case-study and numerical examples, IFTOMM J. Mechanisms Machine Theory 34(4) (1999).Google Scholar
- 14.Vukobratović, M. and Potkonjak, V.: Systems with variable geometry: Concept and prospects, ASME J. Dynamic Systems Meas. Control 121 (April 1999).Google Scholar