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arXiv · 2509.24733

APREBot: Active Perception System for Reflexive Evasion Robot

Zihao Xu·Kuankuan Sima·Junhao Deng·Zixuan Zhuang·Chunzheng Wang·Ce Hao·Jin Song Dong
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Abstract

Reliable onboard perception is critical for quadruped robots navigating dynamic environments, where obstacles can emerge from any direction under strict reaction-time constraints. Single-sensor systems face inherent limitations: LiDAR provides omnidirectional coverage but lacks rich texture information, while cameras capture high-resolution detail but suffer from restricted field of view. We introduce APREBot (Active Perception System for Reflexive Evasion Robot), a novel framework that integrates reflexive evasion with active hierarchical perception. APREBot strategically combines LiDAR-based omnidirectional scanning with camera-based active focusing, achieving comprehensive environmental awareness essential for agile obstacle avoidance in quadruped robots. We validate APREBot through extensive sim-to-real experiments on a quadruped platform, evaluating diverse obstacle types, trajectories, and approach directions. Our results demonstrate substantial improvements over state-of-the-art baselines in both safety metrics and operational efficiency, highlighting APREBot's potential for dependable autonomy in safety-critical scenarios. Videos are available at https://sites.google.com/view/aprebot/

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Zihao Xu, Kuankuan Sima, Junhao Deng, Zixuan Zhuang, Chunzheng Wang, Ce Hao, Jin Song Dong. 2025-09-29. APREBot: Active Perception System for Reflexive Evasion Robot. https://arxiv.org/abs/2509.24733

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