Energy-Shaping Controllers for Soft Robot Manipulators Through Port-Hamiltonian Cosserat Models

Abstract

In this work, we discuss the application of energy-based controller design for under-actuated soft robot manipulators. The continuous dynamics of the soft robot are modeled through the differential geometry of Cosserat beams. Using a finite-dimensional truncation, the system can be written as a reduced port-Hamiltonian model that preserves the passivity condition. Then, a model-based controller is introduced that produces a local minimizer of closed-loop potential energy for the desired end-effector configuration. The stabilizing control utilizes an energy-based approach and exploits the passivity of the soft robotic system. The effectiveness of the energy-based controller is demonstrated through extensive simulations of various soft robotic systems that share a resemblance with biology. All software and numerical studies are provided in an open-access SOROTOKI toolkit written in Matlab.