Huang Kevin, Chitrakar Digesh, Mitra Rahul, Subedi Divas, Su Yun-Hsuan
Annu Int Conf IEEE Eng Med Biol Soc. 2020 Jul;2020:4903-4908. doi: 10.1109/EMBC44109.2020.9176658.
Haptic feedback can render real-time force interactions with computer simulated objects. In several telerobotic applications, it is desired that a haptic simulation reflects a physical task space or interaction accurately. This is particularly true when excessive applied force can result in disastrous consequences, as with the case of robot-assisted minimally invasive surgery (RMIS) and tissue damage. Since force cannot be directly measured in RMIS, non-contact methods are desired. A promising direction of non-contact force estimation involves the primary use of vision sensors to estimate deformation. However, the required fidelity of non-contact force rendering of deformable interaction to maintain surgical operator performance is not well established. This work attempts to empirically evaluate the degree to which haptic feedback may deviate from ground truth yet result in acceptable teleoperated performance in a simulated RMIS-based palpation task. A preliminary user-study is conducted to verify the utility of the simulation platform, and the results of this work have implications in haptic feedback for RMIS and inform guidelines for vision-based tool-tissue force estimation. An adaptive thresholding method is used to collect the minimum and maximum tolerable errors in force orientation and magnitude of presented haptic feedback to maintain sufficient performance.
触觉反馈可以实现与计算机模拟物体的实时力交互。在一些远程机器人应用中，期望触觉模拟能准确反映物理任务空间或交互。当施加过大的力可能导致灾难性后果时，情况尤其如此，例如在机器人辅助微创手术（RMIS）和组织损伤的情况下。由于在RMIS中无法直接测量力，因此需要非接触式方法。非接触式力估计的一个有前景的方向主要涉及使用视觉传感器来估计变形。然而，对于可变形交互的非接触式力渲染所需的保真度，以维持手术操作者的表现，目前尚未得到充分确立。这项工作试图通过实证评估触觉反馈可能与真实情况存在偏差，但在基于RMIS的模拟触诊任务中仍能产生可接受的远程操作性能的程度。进行了一项初步的用户研究，以验证模拟平台的效用，这项工作的结果对RMIS的触觉反馈具有启示意义，并为基于视觉的工具-组织力估计提供指导方针。使用一种自适应阈值方法来收集所呈现触觉反馈在力的方向和大小上的最小和最大可容忍误差，以维持足够的性能。
