The unifying idea for most model-based control approaches for parallel mechanism is to derive a minimal-order dynamics model of the system and then design the corresponding controller. The problem with such a control approach is that the controller needs to change its structure whenever the mechanical system changes its number of degrees-of-freedom. This paper presents a projection-based control scheme for parallel mechanism that works whether the system is overactuated or not; it does not require derivation of the minimal-order dynamics model. Since the dimension of the projection matrix is fixed, the projection-based controller does not need to change its structure whenever the mechanical system changes its number of degrees-of-freedom. The controller also allows to specify lower and upper bounds on the actuator forces/torques, making it suitable not only for the control of parallel manipulators with limited force/torque capability of the actuators but also for backlash-free control of parallel manipulators as well as for control of tendon driven parallel manipulators. The stability of the projection-based controllers is rigourously proved, while the condition for the controllability of parallel manipulators is also derived in detail. Finally, experimental results obtained from a simple parallel mechanism, which changes its degrees-of-freedom, are appended. The results also demonstrate that the maximum actuator torque can be reduced by 20% if the actuator saturation is taken into account by the controller.
Skip Nav Destination
e-mail: farhad.aghili@asc-csa.gc.ca
Article navigation
July 2011
Research Papers
Projection-Based Control of Parallel Mechanisms
Farhad Aghili
Farhad Aghili
Research Scientist
Space Exploration,
e-mail: farhad.aghili@asc-csa.gc.ca
Canadian Space Agency
, Saint-Hubert, QC, J3Y 8Y9, Canada
Search for other works by this author on:
Farhad Aghili
Research Scientist
Space Exploration,
Canadian Space Agency
, Saint-Hubert, QC, J3Y 8Y9, Canadae-mail: farhad.aghili@asc-csa.gc.ca
J. Comput. Nonlinear Dynam. Jul 2011, 6(3): 031009 (8 pages)
Published Online: February 1, 2011
Article history
Received:
January 12, 2010
Revised:
October 25, 2010
Online:
February 1, 2011
Published:
February 1, 2011
Citation
Aghili, F. (February 1, 2011). "Projection-Based Control of Parallel Mechanisms." ASME. J. Comput. Nonlinear Dynam. July 2011; 6(3): 031009. https://doi.org/10.1115/1.4002942
Download citation file:
Get Email Alerts
Cited By
An Efficient Analysis of Amplitude and Phase Dynamics in Networked MEMS-Colpitts Oscillators
J. Comput. Nonlinear Dynam
Influences of Tooth Crack on Dynamic Characteristics of a Multi-Stage Gear Transmission System Considering the Flash Temperature
J. Comput. Nonlinear Dynam (December 2024)
Data-Driven Modeling of Tire–Soil Interaction With Proper Orthogonal Decomposition-Based Model Order Reduction
J. Comput. Nonlinear Dynam (December 2024)
Related Articles
Control of Redundant Mechanical Systems Under Equality and Inequality Constraints on Both Input and Constraint Forces
J. Comput. Nonlinear Dynam (July,2011)
A Simplified Cartesian-Computed Torque Controller for Highly Geared Systems and Its Application to an Experimental Climbing Robot
J. Dyn. Sys., Meas., Control (March,2000)
Adaptive Control of Harmonic Drives
J. Dyn. Sys., Meas., Control (March,2007)
A Combined Scheme for Identification and Robust Torque Control of Hydraulic Actuators
J. Dyn. Sys., Meas., Control (December,2003)
Related Proceedings Papers
Related Chapters
QP Based Encoder Feedback Control
Robot Manipulator Redundancy Resolution
Feedback-Aided Minimum Joint Motion
Robot Manipulator Redundancy Resolution
Pseudoinverse Method and Singularities Discussed
Robot Manipulator Redundancy Resolution