Controlling a CyberOctopus Soft Arm with Muscle-like Actuation
This work addresses control challenges for soft robotics, specifically in bio-inspired systems like octopus arms, representing an incremental advance in applying energy shaping to anatomically realistic models.
The paper tackled controlling a flexible octopus arm model by developing a control-oriented muscle model and integrating it into energy shaping control, avoiding explicit matching conditions and solving via bilevel optimization, with numerical implementation in Elastica demonstrating bio-inspired control experiments.
This paper presents an application of the energy shaping methodology to control a flexible, elastic Cosserat rod model of a single octopus arm. The novel contributions of this work are two-fold: (i) a control-oriented modeling of the anatomically realistic internal muscular architecture of an octopus arm; and (ii) the integration of these muscle models into the energy shaping control methodology. The control-oriented modeling takes inspiration in equal parts from theories of nonlinear elasticity and energy shaping control. By introducing a stored energy function for muscles, the difficulties associated with explicitly solving the matching conditions of the energy shaping methodology are avoided. The overall control design problem is posed as a bilevel optimization problem. Its solution is obtained through iterative algorithms. The methodology is numerically implemented and demonstrated in a full-scale dynamic simulation environment Elastica. Two bio-inspired numerical experiments involving the control of octopus arms are reported.