YoMo: Yoshimura Continuum Manipulator for MR Environment

Area of Science:

• Robotics
• Mechanical Engineering
• Medical Devices

Background:

• Origami robots offer versatile deformation for various applications, especially in medicine.
• Precise control of robotic manipulators is crucial for minimally invasive medical procedures within confined spaces like MRI scanners.

Purpose of the Study:

• To propose and validate a novel origami-based continuum manipulator, the Yoshimura continuum manipulator (YoMo), for accurate tip positioning in magnetic resonance (MR) environments.
• To develop and evaluate advanced modeling and control strategies for the YoMo, enabling precise trajectory tracking under varying conditions.

Main Methods:

• Design and fabrication of the YoMo using the Yoshimura folding pattern from a single sheet of paper, actuated by cables for bending and shortening.
• Development of a kinematics model based on constant curvature assumption for benchmark prediction and application of Koopman operator theory for orientation-dependent tip position modeling.
• Implementation of a Koopman-based linear quadratic regulator (K-LQR) for trajectory tracking control and experimental validation of YoMo performance, including stiffness and workspace.

Main Results:

• The Koopman-based model significantly outperformed the constant curvature model in predicting the YoMo's tip position.
• Experimental results confirmed the YoMo's capability for accurate trajectory tracking across different orientations, speeds, and trajectories.
• Characterization of YoMo's stiffness and workspace demonstrated its suitability for practical applications.

Conclusions:

• The proposed Yoshimura continuum manipulator (YoMo) offers a viable solution for precise robotic manipulation within MR environments.
• The Koopman operator theory-based modeling and K-LQR control strategy provide superior accuracy and robustness for trajectory tracking.
• YoMo's design and performance indicate strong potential for future medical applications requiring MR compatibility and high dexterity.