학술논문

Robust Control of a Multi-Axis Shape Memory Alloy-Driven Soft Manipulator
Document Type
Periodical
Source
IEEE Robotics and Automation Letters IEEE Robot. Autom. Lett. Robotics and Automation Letters, IEEE. 7(2):2210-2217 Apr, 2022
Subject
Robotics and Control Systems
Computing and Processing
Components, Circuits, Devices and Systems
Actuators
Soft robotics
Robot sensing systems
Three-dimensional displays
Thermal stability
MIMO communication
Dynamics
Modeling
control
and learning for soft robots
Language
ISSN
2377-3766
2377-3774
Abstract
Control of soft robotic manipulators remains a challenge for designs with advanced capabilities and novel actuation. Two significant limitations are multi-axis, three-dimensional motion of soft bodies alongside actuator dynamics and constraints, both of which are present in shape-memory-alloy (SMA)-powered soft robots. This article addresses both concerns with a robust feedback control scheme, demonstrating state tracking control for a soft robot manipulator of this type. Our controller uses a static beam bending model to approximate the soft limb as an LTI system, alongside a singular-value-decomposition compensator approach to decouple the multi-axial motion and an anti-windup element for the actuator saturation. We prove stability and verify robustness of our controller, with robustness intended to account for the unmodeled dynamics. Our implementation is verified in hardware trajectory tracking tests of a soft SMA-powered limb with accurate, promising results for future multi-limbed robots.