Methods And Mechanisms For Contact Feedbackin A Robot-Assisted Minimally Invasive Environment

Abstract—Providing a surgeon with information regarding contacts made between instruments and tissue during robot-assisted interventions can improve task efficiency and reliability. In this paper, different methods for feedback of such information to the surgeon are discussed. It is hypothesized that various modalities of contact feedback have the potential to enhance performance in a robot-assisted minimally invasive environment. To verify the hypothesis, novel mechanisms needed for incorporating contact feedback are designed including a surgeon-robot interface with full force feedback capabilities and a surgical end-effector with full force sensing capabilities, which are suitable for minimally invasive applications. These two mechanisms are used to form a robotic “master-slave” test-bed for studying the effect of contact feedback on the system and user performance. Using the master-slave system, experiments for surgical tasks involving soft-tissue palpation are conducted. The performance of the master-slave system is validated in terms of criteria that assess the accurate transmission to the surgeon of task-related information, which is critical in the context of soft-tissue surgical applications. Moreover, using a set of experiments involving human subjects, the performance of several users in carrying out the task is compared for different modalities of contact feedback.