Optimization-based automated generation of 1-DOF multi-section continuum robots with predefined end-effector poses

Abstract

Continuum robots have been widely utilized in various fields, such as medical surgery, industrial manufacturing, and aerospace, due to their flexibility and compliance. However, their high structural compliance also presents significant challenges in achieving precise control. Although many existing continuum robots feature multiple degrees-of-freedom (DOFs) and complex control systems, such sophistication is often unnecessary for simple, repetitive, and task-specific applications where task-specific structures are more efficient. To address this issue, this paper proposes a parametric optimization-based automated design framework to generate structural models for multi-section 1-DOF flexure-joint-based continuum robots capable of achieving any two predefined end-effector poses. The proposed methodology employs a constant curvature assumption to simulate the bending characteristics of the continuum robot. MATLAB is used to optimize and solve the structural parameters, followed by the generation of 3D-printable models using the Solid Geometry Library Toolbox. Experimental results demonstrate that, under certain geometric boundary conditions for structural parameters, the robot’s end-effector can reach any two predefined poses with high accuracy. This approach significantly reduces the structural and control complexity of task-specific continuum robots, lowers manufacturing costs, and expands their range of applications.

Keywords

Automated generation / Task-specific continuum robot / Parameter optimization / Flexure joint

CRediT authorship contribution statement

Jiake Fu: Writing – original draft, Validation, Software, Methodology, Investigation, Formal analysis, Conceptualization. Zengwei Wang: Validation. Felix Pancheri: Resources. Tim C. Lueth: Funding acquisition. Yilun Sun: Writing – review & editing, Supervision, Project administration, Funding acquisition, Conceptualization.

Declaration of competing interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Acknowledgment

This research is supported by the teaching funding of TUM School of Engineering and Design .

Appendix A. Supplementary data

Movie S1. Demonstration video of the continuum robot structure and experimental results with three physical prototypes. The video illustrates the mechanical design, structural features, and how each prototype achieves predefined end-effector poses.

Code S1. Arc parameter optimization code.

Code S2. SGCL code for flexible section model generation.

Code S3. SGCL code for complete continuum robot model generation.

Supplementary material related to this article can be found online at https://doi.org/10.1016/j.birob.2026.100276.

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