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## Experimental study for the Six-DOF parallel forging manipulator

#### Abstract

This thesis covers the motion planning and experimental study for the lifting system of a six DOF parallel forging manipulator. This forging manipulator is capable of handling a maximum load of that can generate a maximum moment at the Tool Centre Point of . The task that had to be studied consists of three stages: lifting, followed by a holding stage during which the gripper support maintains its position but the manipulator will move along its tracks. In the last stage of the motion the gripper is lowered . The motion is performed while the gripper is holding the work-piece. Because of the mentioned task, only the lifting mechanism had to be analysed, so the spatial six DOF robot was reduced to a planar three DOF manipulator. In order to solve the tasks defined for this project, the work was divided into four parts. The first part consist of studying why the need for this kind of handling robots occurred in the first place and investigating existing forging manipulators. The investigation stage consists of analysing manipulator architectures, driving units, control systems and so on. In the second part of the project the kinematic and dynamic modelling was performed. In both cases, the multibody system approach with absolute coordinates was used. This method was never before been employed in the modelling of forging manipulators. This approach reduced the computational complexity and also gave me the option of validating the MATLAB model with ADAMS. First the direct kinematic model was developed, then the inverse and later the dynamic. The crucial results from the modelling stage are the translational displacements of the pistons and the driving forces inside the actuated hydraulic cylinders. These will be used later on as command signals for the control system. After a correct model was found, the motion plan of the Tool Centre Point was developed. Because the TCP has to perform a simple lifting/lowering motion (along the vertical axis) with constant orientation, getting the motion plan means finding an appropriate point-to-point interpolation model. Two were considered: fifth degree polynomial and smooth trapezoidal velocity. In the end, the trapezoidal model was chosen for the TCP’s motion. This interpolation model was set as input for the Inverse Kinematic Problem and further ADAMS validations were performed. After the results from the Inverse Kinematic and Dynamic Problems were thoroughly validated through simulations, the PLC code controlling the hydraulic system was adjusted to easily accept the obtained translational displacements and driving forces as command signals. To every result set, a polynomial function was fitted to further reduce the complexity of setting my inputs to the control system. Some experiments were performed on the existing manipulator, but, later on, the researchers from SJTU will perform a more extensive study using the results from my MATLAB models.
Record ID
WUT0e9a6d04ea684e0987ef39f4b1286af6
Diploma type
Master of Science
Author
Sergiu-Bogdan Mada (FPAE/IAAM) Sergiu-Bogdan Mada,, The Institute of Aeronautics and Applied Mechanics (FPAE/IAAM)Faculty of Power and Aeronautical Engineering (FPAE)
Title in Polish
Supervisor
Krzysztof Mianowski (FPAE/IAAM) Krzysztof Mianowski,, The Institute of Aeronautics and Applied Mechanics (FPAE/IAAM)Faculty of Power and Aeronautical Engineering (FPAE)
Certifying unit
Faculty of Power and Aeronautical Engineering (FPAE)
Affiliation unit
The Institute of Aeronautics and Applied Mechanics (FPAE/IAAM)
Language
(en) English
Status
Finished
Defense Date
11-09-2012
Issue date (year)
2012
Pages
66
Internal identifier
MEL; PD-2034
Reviewers
Krzysztof Mianowski (FPAE/IAAM) Krzysztof Mianowski,, The Institute of Aeronautics and Applied Mechanics (FPAE/IAAM)Faculty of Power and Aeronautical Engineering (FPAE) Yong Zhang Yong Zhang,, Undefined Affiliation Rezia Molfino Rezia Molfino,, Undefined Affiliation
Keywords in Polish
manipulator do obslugi procesów kucia, uklad wieloczlonowy, modelowanie kinematyki i dynamiki, planowanie trajektorii
Keywords in English
forging manipulator, multibody system, kinematic and dynamic modelling, trajectory planning
Abstract in Polish
urn:pw-repo:WUT0e9a6d04ea684e0987ef39f4b1286af6