Manipulation of objects within a robot's hand is one of the most important challenges in achieving robot dexterity. The "Roller Graspers" refers to a family of non-anthropomorphic hands utilizing motorized, rolling fingertips to achieve in-hand manipulation. These graspers manipulate grasped objects by commanding the rollers to exert forces that propel the object in the desired motion directions. In this paper, we explore the possibility of robot in-hand manipulation through tactile-guided rolling. We do so by developing the Tactile-Reactive Roller Grasper (TRRG), which incorporates camera-based tactile sensing with compliant, steerable cylindrical fingertips, with accompanying sensor information processing and control strategies. We demonstrated that the combination of tactile feedback and the actively rolling surfaces enables a variety of robust in-hand manipulation applications. In addition, we also demonstrated object reconstruction techniques using tactile-guided rolling. A controlled experiment was conducted to provide insights on the benefits of tactile-reactive rollers for manipulation. We considered two manipulation cases: when the fingers are manipulating purely through rolling and when they are periodically breaking and reestablishing contact as in regrasping. We found that tactile-guided rolling can improve the manipulation robustness by allowing the grasper to perform necessary fine grip adjustments in both manipulation cases, indicating that hybrid rolling fingertip and finger-gaiting designs may be a promising research direction.

翻译：实现机器人手内物体操控是达成机器人灵巧操作的最重要挑战之一。“滚轮夹持器”指一类非拟人化手部设计，利用电动滚轮指尖实现手内操控。这类夹持器通过指令滚轮施加作用力，推动物体沿预期运动方向运动，从而操控被抓取物体。本文探索了通过触觉引导滚轮实现机器人手内操控的可能性。为此，我们开发了触觉反应式滚轮夹持器（TRRG），该装置将基于摄像头的触觉传感与可操控的柔性圆柱形指尖相结合，并配备了相应的传感器信息处理与控制策略。实验证明，触觉反馈与主动滚轮表面的结合能够实现多种鲁棒的手内操控应用。此外，我们还展示了利用触觉引导滚轮的物体重建技术。通过控制实验揭示了触觉反应式滚轮对操控性能的增益效果。我们考察了两种操控场景：手指完全通过滚轮运动进行操控，以及手指如重新抓取般周期性断开并重建接触。研究发现，触觉引导滚轮能在两种操控场景中使夹持器进行必要的精细抓取调整，从而提升操控鲁棒性，这表明混合滚轮指尖与手指步态设计可能成为有前景的研究方向。