Locomotion of an Elastic Snake Robot via Natural Dynamics

2026-04-20

AI Summary

This study addresses the low locomotion efficiency of compliant serpentine robots by proposing a novel gait design method grounded in natural dynamics. The approach achieves theoretically 100% energy efficiency under energy-conserving conditions by switching between nonlinear normal modes and, for the first time, employing non-brake periodic orbits to drive locomotion. Leveraging invariant manifold theory, the authors analyze the system’s nonlinear dynamics and validate multiple gait strategies through numerical simulations. Results demonstrate that the proposed non-brake orbit gait attains perfect efficiency in idealized settings and significantly outperforms existing benchmarks based on rigid-body systems even in the presence of friction, highlighting its innovation and practical potential for energy-efficient motion control.

Technology Category

• Intelligent Robots: Motion and Path Planning
• Search and Optimization: Sampling/Simulation-based Search
• Computer Vision: Low Level & Physics-based Vision

Application Category

• Graph Algorithms and Modeling for the Web: Efficient manipulation of static and dynamic Web-related graphs
• Systems and Infrastructure for Web, Mobile and WoT: Energy management for devices in mobile Web and WoT environments
• Search and Retrieval-Augmented AI: Efficiency and scalability of Web search engines

Abstract

Nature suggests that exploiting the elasticities and natural dynamics of robotic systems could increase their locomotion efficiency. Prior work on elastic snake robots supports this hypothesis, but has not fully exploited the nonlinear dynamic behavior of the systems. Recent advances in eigenmanifold theory enable a better characterization of the natural dynamics in complex nonlinear systems. This letter investigates if and how the nonlinear natural dynamics of a kinematic elastic snake robot can be used to design efficient gaits. Two types of gaits based on natural dynamics are presented and compared to a state-of-the-art approach using dynamics simulations. The results reveal that a gait generated by switching between two nonlinear normal modes does not improve the locomotion efficiency of the robot. In contrast, gaits based on non-brake periodic trajectories (non-brake orbits) are perfectly efficient in the energy-conservative case. Further simulations with friction reveal that, in a more realistic scenario, non-brake orbit gaits achieve higher efficiency compared to the baseline gait on the rigid system. Overall, the investigation offers promising insights into the design of gaits based on natural dynamics, fostering further research.

Problem

• elastic snake robot
• natural dynamics
• locomotion efficiency
• nonlinear normal modes
• non-brake orbits

Innovation

• natural dynamics
• nonlinear normal modes
• non-brake orbits
• elastic snake robot
• eigenmanifold theory