Optimal redundancy resolution for kinematically redundant parallel manipulators

Tunç, Tansel Sıtkı
In this study, the redundancy resolution of kinematically redundant parallel manipulators has been investigated as an optimization problem. The emerging optimization problem has been solved globally using a hybrid genetic algorithm. This algorithm has been applied as an example to a planar parallel manipulator which has four degrees of freedom. It has been assumed that the manipulator is used so that only the tip point of its end-effector is controlled. Therefore, the rotation angle of the end effector has been let free. As a result, the redundancy degree of the manipulator has become two for the planar point positioning task which requires two degrees of freedom. In the definiton of the optimiziation problem, the limits of the prismatic joints have acted as inequality constraints and the kinematic relationships, which consist of the loop closure and input-output equations between the tip point position and the joint variables, have acted as equality constraints. It has been assumed that the revolute joints have no limit. Various performance functions such as potential energy, kinetic energy and total power have been used for the purpose of optimization. By minimizing each function separately, different optimal redunancy resolutions have been obtained at the position, velocity and acceleration levels.


IDER, SK (1996-01-03)
In this paper inverse dynamics of redundant multibody systems using a minimum number of control forces is formulated. It is shown that the control forces and the task accelerations may become noncausal at certain configurations, yielding the dynamical equation set of the system to be singular. For a given set of tasks, each different set of actuators leads to a different system motion and also to different singular configurations. To avoid the singularities in the numerical solution, the dynamical equations...
Linearization and optimization of robot dynamics via inertial parameter design
Soylu, Reşit (1996-08-01)
In this article, the concept of linearity number (LN) is introduced to measure the ''linearity'' of the equations of motion of a serial manipulator. This number is computable in closed-form and is an average quantitative index of the degree of linearity of the robot over a specified region in the joint space. The definition is flexible, allowing the user to create custom-made definitions according to his or her specific needs. Using the concept of LN and the developed computer package CADLOR, one can design...
Forward Kinematics of the 6-6 general Parallel Manipulator Using Real Coded Genetic Algorithms
Rolland, Luc; Chandra, Rohitash (2009-07-17)
This article examines an optimization method to solve the forward kinematics problem (FKP) applied to parallel manipulators. Based on Genetic Algorithms (GA), a non-linear equation system solving problem is converted into an optimization one. The majority of truly parallel manipulators can be modeled by the 6-6 which is an hexapod constituted by a fixed base and a mobile platform attached to six kinematics chains with linear (prismatic) actuators located between two ball joints. Parallel manipulator kinemat...
Practical Implementation of Generalized Force Vectors for the Multimodal Pushover Analysis of Building Structures
Alici, F. Soner; Sucuoğlu, Haluk (SAGE Publications, 2015-05-01)
A practical implementation of generalized multimodal pushover analysis is presented in this study, where the number of pushovers is reduced significantly in view of the number of modes contributing to seismic response. It has been demonstrated in two case studies that the reduced procedure for generalized pushover analysis is equally successful in estimating the maximum member deformations and forces under a ground excitation with reference to nonlinear response history analysis. It is further shown that th...
Invalid joint arrangements and actuator related singular configurations of a system of two cooperating SCARA manipulators
Ozkan, B; Özgören, Mustafa Kemal (2001-06-01)
In this study, the actuator related singular configurations (ASCs) of a system of two cooperating SCARA manipulators, are investigated. The ASC concept was First developed for planar pairs of cooperating manipulators, and it was shown that these ill-conditions could be different from the kinematic: singularities. (Ozkan B, Ozgoren MK. Torque related singular configurations of a planar system of two coodinated manipulators. In: Proceedings of International Machine Design and Production Conference, Sept. 9-11...
Citation Formats
T. S. Tunç, “Optimal redundancy resolution for kinematically redundant parallel manipulators,” M.S. - Master of Science, Middle East Technical University, 2014.