Reinforcement Learning on Cost-Constrained Quadrupedal Hardware

Javier C. Weddington; Bence P. Ölveczky; Stephen A. Baccus

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arXiv · 2607.26434

Reinforcement Learning on Cost-Constrained Quadrupedal Hardware

Javier C. Weddington·Bence P. Ölveczky·Stephen A. Baccus

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Abstract

Deploying learned control policies on low-cost robotic platforms introduces transport latencies and noisy motor feedback that systematically widens the sim-to-real gap. The chasm of simulation to deployment in hardware lies in the delay of the actuator reaching the commanded position. On platforms such as the Mini Pupper 2, a measured >50 ms transport delay transforms the locomotion task from a standard Markov decision process into a partially observable one. In this paper, we take a biologically inspired approach of handling noisy and delayed feedback to close the sim-to-real gap, thereby expanding the capability of reinforcement learning on cost-constrained hardware. Using a low-cost quadrupedal hardware platform, we find that using a forward model of the average actuator delay, paired with a time-aware neural network results in robust locomotion. Additionally, our time-aware neural network learned a central pattern generator (CPG): a self-sustaining rhythmic gait that is robust to +320 ms latency perturbations, mirroring the CPGs found in the spinal cords of vertebrates. We posit that temporal self-organization may be a general strategy for cost-constrained locomotion.

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BibTeX RIS

Javier C. Weddington, Bence P. Ölveczky, Stephen A. Baccus. 2026-07-29. Reinforcement Learning on Cost-Constrained Quadrupedal Hardware. https://arxiv.org/abs/2607.26434

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