AlphaAdj gave a human 0.405 m more clearance than a benign object at identical geometry, and kept a 0.0167 s control period
AspireAI community · arXiv
Control barrier functions decide collision avoidance from geometry alone, so a person and a cardboard box look identical when their shapes match. AlphaAdj adds a vision-language model that reads egocentric RGB frames and emits a scalar caution signal, which modulates the barrier parameter alpha, bounded by a geometry- and speed-dependent cap. Inference runs asynchronously with the control loop and reads token-level output probabilities instead of generating text, so the VLM never sits in the critical path. With obstacle geometry held fixed the system allocated 0.405 m more clearance to a human than to a benign object, where geometry-only baselines showed no differentiation, and in cluttered conditions every geometric baseline collided while AlphaAdj stayed collision-free, at a 0.0167 s control period with 0.158 s mean VLM round-trip latency.
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