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Full-Text Articles in Mechanical Engineering
Robust Nonlinear Control Of Brushless Dc Motors For Direct-Drive Robotic Applications, N. Hemati, J. S. Thorp, Ming-Chuan Leu
Robust Nonlinear Control Of Brushless Dc Motors For Direct-Drive Robotic Applications, N. Hemati, J. S. Thorp, Ming-Chuan Leu
Mechanical and Aerospace Engineering Faculty Research & Creative Works
The control problem associated with brushless DC motors (BLDCMs) for direct-drive robotic applications is considered. In order to guarantee the high-performance operation of BLDCMs in such applications, the effects of reluctance variations and magnetic saturation are accounted for in the model. Such a BLDCM model constitutes a highly coupled and nonlinear dynamic system. Using the transformation theory of nonlinear systems, a feedback control law, which is shown to compensate for the system nonlinearities, is derived. Conditions under which such a control law is possible are presented. The need for the derivation of explicit commutation strategies is eliminated, resulting in reduction …
Planning Optimal Robot Trajectories By Cell Mapping, W. H. Zhu, Ming-Chuan Leu
Planning Optimal Robot Trajectories By Cell Mapping, W. H. Zhu, Ming-Chuan Leu
Mechanical and Aerospace Engineering Faculty Research & Creative Works
A cell-mapping method is introduced for planning global trajectories of robotic manipulators in cases where the cell space is composed of combination pairs of plane cells. With the proposed method, optimal trajectory problems in the free field and in the obstacle-constrained field are studied. Two numerical examples are given to show the obtained optimal trajectories and controls.
Robust Nonlinear Control Of Brushless Dc Motors In The Presence Of Magnetic Saturation, N. Hemati, J. S. Thorp, Ming-Chuan Leu
Robust Nonlinear Control Of Brushless Dc Motors In The Presence Of Magnetic Saturation, N. Hemati, J. S. Thorp, Ming-Chuan Leu
Mechanical and Aerospace Engineering Faculty Research & Creative Works
A robust control law is derived and examined for a direct-drive robot arm driven by a brushless DC motor (BLDCM). The complete dynamics of the motor and its interaction with the robot arm are accounted for. This is important, since in a direct-drive servo system the torque generated by the motor is directly transmitted to the load. Effects of magnetic saturation as well as reluctance variations are accounted for, in order to ensure accuracy. The effectiveness of the method is examined through computer simulations. The computational complexity of the overall control scheme is such that it can be readily used …