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This content will become publicly available on October 1, 2023

Title: Task-Space Control of Continuum Robots using Underactuated Discrete Rod Models
Underactuation is a core challenge associated with controlling soft and continuum robots, which possess theoretically infinite degrees of freedom, but few actuators. However, m actuators may still be used to control a dynamic soft robot in an m-dimensional output task space. In this paper we develop a task-space control approach for planar continuum robots that is robust to modeling error and requires very little sensor information. The controller is based on a highly underactuated discrete rod mechanics model in maximal coordinates and does not require conversion to a classical robot dynamics model form. This promotes straightforward control design, implementation and efficiency. We perform input-output feedback linearization on this model, apply sliding mode control to increase robustness, and formulate an observer to estimate the full state from sparse output measurements. Simulation results show exact task-space reference tracking behavior can be achieved even in the presence of significant modeling error, inaccurate initial conditions, and output-only sensing.
Award ID(s):
1935278 1652588
Publication Date:
Journal Name:
Proceedings of the IEEERSJ International Conference on Intelligent Robots and Systems
Sponsoring Org:
National Science Foundation
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