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Title: Directional Stiffness Modulation of Parallel Robots with Kinematic Redundancy and Variable Stiffness Joints
Parallel robots have been primarily investigated as po- tential mechanisms with stiffness modulation capabilities through the use of actuation redundancy to change internal preload. This paper investigates real-time stiffness modula- tion through the combined use of kinematic redundancy and variable stiffness actuators. A known notion of directional stiffness is used to guide the real-time geometric reconfig- uration of a parallel robot and command changes in joint- level stiffness. A weighted gradient-projection redundancy resolution approach is demonstrated for resolving kinematic redundancy while satisfying the desired directional stiffness and avoiding singularity and collision between the legs of a Gough/Stewart parallel robot with movable anchor points at its base and with variable stiffness actuators. A simulation study is carried out to delineate the effects of using kinematic redundancy with or without the use of variable stiffness ac- tuators. In addition, modulation of the entire stiffness matrix is demonstrated as an extension of the approach for modulating directional stiffness.  more » « less
Award ID(s):
1734461
NSF-PAR ID:
10097563
Author(s) / Creator(s):
;
Date Published:
Journal Name:
Journal of Mechanisms and Robotics
ISSN:
1942-4302
Page Range / eLocation ID:
1-14
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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