Inverse dynamics control of flexible joint parallel manipulators

Download

index.pdf

Date

2006

Author

Korkmaz, Ozan

Metadata

Show full item record

Item Usage Stats

264
views

72
downloads

The purpose of this thesis is to develop a position control method for parallel manipulators so that the end effector can follow a desired trajectory specified in the task space where joint flexibility that occurs at the actuated joints is also taken into consideration. At the beginning of the study, a flexible joint is modeled, and the equations of motion of the parallel manipulators are derived for both actuator variables and joint variables by using the Lagrange formulation under three assumptions regarding dynamic coupling between the links and the actuators. These equations of motion are transformed to an input/output relation between the actuator torques and the actuated joint variables to achieve the trajectory tracking control. Moreover, the singular configurations of the parallel manipulators are explained. As a case study, a three degree of freedom, two legged planar parallel manipulator is simulated considering joint flexibility. The structural damping of the active joints, viscous friction at the passive joints and the rotor damping are also considered throughout the study. Matlab® and Simulink® softwares are used for the simulations. The results of the simulations reveal that steady state errors are negligibly small and good tracking performances can be achieved.

Subject Keywords

Mechanical Devices and Figures., Robots (General), Ingenious Mechanisms., Automata.

URI

http://etd.lib.metu.edu.tr/upload/3/12608084/index.pdf
https://hdl.handle.net/11511/16478

Collections

Graduate School of Natural and Applied Sciences, Thesis

Suggestions

OpenMETU
Core

Modeling and control of constrained flexible joint parallel manipulators Oğan, Osman Can; İder, Kemal; Department of Mechanical Engineering (2010) The purpose of the thesis is to achieve a hybrid force and motion control method of parallel manipulators working in a constrained environment, in the presence of joint flexibility that occurs at the actuated joints. A flexible joint is modeled and the equations of motion of the parallel manipulator are derived by using the Lagrange formulation. The structural damping of the active joints, viscous friction at the passive joints and the rotor damping are also considered in the model. It is shown that in a fl...
Singularity robust inverse dynamics of planar 2-RPR parallel manipulators Ider, SK (SAGE Publications, 2004-07-01) In planar parallel robots, limitations occur in the functional workspace because of interference of the legs with each other and because of drive singularities where the actuators lose control of the moving platform and the actuator forces grow without bounds. A 2-RPR (revolute, prismatic, revolute joints) planar parallel manipulator with two legs that minimizes the interference of the mechanical components is considered. Avoidance of the drive singularities is in general not desirable since it reduces the ...
Design, development and manufacturing of an all terrain modular robot platform Kul, Mustafa Cihangir; Koku, Ahmet Buğra; Department of Mechanical Engineering (2010) The aim of this thesis is to create a flexible multi-purpose modular all terrain robot platform, which has the potential to be used in commercial applications as well as in education and research. In developing this robot platform, it is aimed to use readily available commercial products as much as possible in order to keep the cost of the product low, increase maintainability, and benefit from the improvements made to these components in time. The modularity is attained by designing a two wheeled base modu...
Inverse dynamics control of parallel manipulators around singular configurations Özdemir, Mustafa; İder, S. Kemal; Department of Mechanical Engineering (2008) In this thesis, a technique for the motion of parallel manipulators through drive singularities is investigated. To remedy the problem of unbounded inverse dynamics solution in the neighborhood of drive singularities, an inverse dynamics controller which uses a conventional inverse dynamics control law outside the neighborhood of singularities and switches to the mode based on the formerly derived modified equations inside the neighborhood of singularities is proposed. As a result, good tracking performance...
Analysis of thin walled open section tapered beams using hybrid stress finite element method Akman, Mehmet Nazım; Oral, Süha; Department of Mechanical Engineering (2008) In this thesis, hybrid stress finite element is formulated for the analysis of the isotropic, thin walled, open section beams with variable cross sections. The beam element has two nodes each having seven degrees of freedom. Assumption of stress field is sufficient to determine the element stiffness matrix. Axial, flexural and torsional effects are taken into account in the analysis. The methodology can be applied both to the tapered and the uniform beams. Throughout this study, firstly element cross-sectio...

Citation Formats

O. Korkmaz, “Inverse dynamics control of flexible joint parallel manipulators,” M.S. - Master of Science, Middle East Technical University, 2006.