Robotic Arm-Assisted Closed-Loop Control of a Magnetoactive Soft Continuum Robot in Nonuniform Magnetic Fields

Abstract

In recent years, magnetoactive soft continuum robots (MSCRs) with versatile locomotion capabilities have received significant interest in wide range of biomedical applications. Developing effective control methods for MSCRs is essential to achieve precise navigation within the human body. Although several studies have demonstrated closed-loop control using uniform magnetic fields generated by magnetic coils, such methods are generally impractical for human-scale workspaces. This study presents a practical closed-loop control strategy for MSCRs using gradient magnetic fields generated by a rotatable permanent magnet integrated with a robotic arm. In this study, a novel Feedforward-Feedback Proportional-Integral-Derivative (FFPID) control strategy is proposed to accurately guide the MSCR along desired trajectories. The MSCR is first fabricated and subjected to comprehensive mechanical and magnetic characterization. Subsequently, a hardware-in-the-loop (HIL) setup is implemented to evaluate the performance of the developed FFPID control strategy. Experimental results confirm the effectiveness of the proposed FFPID method, demonstrating precise trajectory tracking and robust performance.