School of Engineering, Trinity College Dublin, D02 PN40 Dublin, Ireland.
Sensors (Basel). 2021 Dec 14;21(24):8339. doi: 10.3390/s21248339.
A robot's ability to grasp moving objects depends on the availability of real-time sensor data in both the far-field and near-field of the gripper. This research investigates the potential contribution of tactile sensing to a task of grasping an object in motion. It was hypothesised that combining tactile sensor data with a reactive grasping strategy could improve its robustness to prediction errors, leading to a better, more adaptive performance. Using a two-finger gripper, we evaluated the performance of two algorithms to grasp a ball rolling on a horizontal plane at a range of speeds and gripper contact points. The first approach involved an adaptive grasping strategy initiated by tactile sensors in the fingers. The second strategy initiated the grasp based on a prediction of the position of the object relative to the gripper, and provided a proxy to a vision-based object tracking system. It was found that the integration of tactile sensor feedback resulted in a higher observed grasp robustness, especially when the gripper-ball contact point was displaced from the centre of the gripper. These findings demonstrate the performance gains that can be attained by incorporating near-field sensor data into the grasp strategy and motivate further research on how this strategy might be expanded for use in different manipulator designs and in more complex grasp scenarios.
机器人抓取移动物体的能力取决于夹持器远场和近场中实时传感器数据的可用性。本研究探讨了触觉传感在抓取运动物体任务中的潜在贡献。研究假设,将触觉传感器数据与反应式抓取策略相结合,可以提高其对预测误差的鲁棒性,从而实现更好、更适应的性能。我们使用两指夹持器评估了两种算法在不同速度和夹持器接触点下抓取在水平面上滚动的球的性能。第一种方法涉及由手指中的触觉传感器启动的自适应抓取策略。第二种策略基于对物体相对于夹持器位置的预测启动抓取,并为基于视觉的物体跟踪系统提供代理。研究发现,触觉传感器反馈的集成导致观察到的抓取鲁棒性更高,特别是当夹持器-球接触点从夹持器中心偏移时。这些发现表明,通过将近场传感器数据纳入抓取策略,可以获得性能提升,并激发进一步研究如何将这种策略扩展用于不同的操纵器设计和更复杂的抓取场景。