Exploring Nonlinear Body Oscillations for Natural Quadruped Gaits

2026-08-31

AI Summary

研究通过调整四足机器人的非线性动力学，利用机械共振产生多步态运动，以减少主动控制需求，提高效率。

Abstract

Animals' body morphology shapes the gait patterns they can perform, where mechanical resonance reduces the need for active control. By tuning posture and muscle stiffness, they leverage their embodied intelligence to achieve effective gaits for different speeds. In contrast, most quadruped robots are not specifically designed to exploit mechanical resonance due to the complexity of nonlinear dynamics and require dedicated locomotion controllers. To provide an alternative, we present a proof of concept framework making the nonlinear dynamics of a robot predictable in the design process and show how this knowledge can be leveraged such that multi-gait locomotion can emerge from nonlinear resonances, shaped by gravity, inertia, and elasticity. We present the highly compliant quadruped robot eBert, on which we identify six nonlinear normal modes (NNMs) using our new theoretical tools and validate their existence in simulation and hardware. With black-box optimization to determine step length, simulations show how each NNM naturally develops into a distinct gait, manifesting different speeds, which also largely transfers to the robotic hardware. Our experiments show that eBert can exploit its mechanics to generate task-specific movements which may serve as foundation for designing a new generation of agile and efficient robots leveraging embodied intelligence.

Problem

• nonlinear dynamics
• mechanical resonance
• quadruped robots
• embodied intelligence
• multi-gait locomotion

Innovation

• nonlinear normal modes (NNMs)
• black-box optimization
• embodied intelligence