未知阻力下视觉运动策略的意图引导自适应刚度增强
Intent-guided Adaptive Stiffening for Visuomotor Policies under Unknown Resistance
AI总结：
针对未知阻力下视觉运动策略无法提供足够控制力的问题，提出无需额外训练的残差刚度增强层，通过运动不匹配识别阻力，在两项任务上将成功率提至90%，峰值离轴力降61%。
摘要：
拧开瓶盖或在表面滑动零件等操作任务需要沿高摩擦方向施加力：机器人必须克服阻力而非屈服于它。生成式视觉运动策略可预测此类任务的运动，但无法提供实现该运动所需的控制力，而该控制力受其下方阻抗控制器的限制：当阻力超过柔顺控制器在有界跟踪误差下可施加的力时，无论预测多么准确，任务都无法完成。所需控制力也无法提前预知，因为它取决于观测未揭示的接触状态。本文提出一种置于未修改策略下方的残差刚度增强层。该层无需力传感，通过策略命令的运动与机器人实际实现的运动之间的不匹配来识别阻力，且一个四模式控制器会沿策略自身动作块读取的单一方向提高刚度，在任务进行时保持该刚度，任务完成后释放。该层无需柔顺标签、无需重新训练、无需重新收集演示。在两项真实任务（拧开瓶盖、沿T型槽推动T型螺母对抗非均匀摩擦）上，针对六个阻力水平（其中两个未在演示中出现）进行评估，结果显示，与相同阻力下的均匀刚度控制器相比，该层将成功率从52%提升至90%，同时产生的峰值离轴力减少了61%。
英文摘要：
Manipulation tasks such as unscrewing a cap or sliding a part in contact with a surface require imposing force along a high-friction direction: the robot must overcome a resistance rather than yield to it. Generative visuomotor policies predict the motion for such tasks but not the authority needed to realize it, and that authority is bounded by the impedance controller beneath them: when the resistance exceeds what a compliant controller can exert under a bounded tracking error, the task is unattainable however accurate the prediction is. The required amount cannot be anticipated either, since it depends on a contact state the observation does not reveal. In this paper, we propose a residual stiffening layer placed underneath an unmodified policy. Resistance is recognized, without force sensing, from the mismatch between the motion the policy commands and the motion the robot realizes, and a four-mode supervisor raises the stiffness along a single direction read off the policy's own action chunk, retains it while the task progresses and releases it afterwards. The layer needs no compliance labels, no retraining and no re-collected demonstrations. On two real tasks, unscrewing a bottle cap and pushing a T-nut along a T-slot groove against non-homogeneous friction, evaluated at six resistance levels of which two were withheld from the demonstrations, the layer raises the success rate from 52% to 90% while producing 61% less peak off-axis force than a uniformly stiff controller at the same resistance.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
