Sparse human corrections took a robot's precision task success from 33.3 to 75.0 percent, and concentrated learning into a 2-3 dimensional subspace of seven joints
AspireAI community · arXiv
Imitation policies that execute most of a manipulation trajectory can still fail in small regions that need last-mile precision, and the usual fix - retrain the whole policy or explore residual actions everywhere - treats a local failure as a global learning problem. Adaptive Residual Correction instead freezes the policy and learns a residual on top of it with reinforcement learning, using sparse human corrections to structure where and when that refinement happens, while task reward decides what residual is actually executed. On three precision-manipulation tasks on a real robot, average task success rose from 33.3 percent to 75.0 percent. The striking detail is where the human signal went: the corrections defined task-dependent 2-3 dimensional subspaces of the seven-joint residual action space that retained 96.0 to 97.7 percent of the squared correction magnitude, so a handful of demonstrations narrowed the search rather than setting the target.
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