Ultrasound Guided Diagnostic and Surgical Robots

This thesis describes the development of four robotic platforms for medical applications which enable human-robot interaction for diagnostic imaging, surgical planning, and ultrasound (US) guided procedures. A dual-robot framework for US-guided needle placement was designed with the aim to provide a solution that encompasses the difficulties in performing needle placement in specific surgical procedures such as cryoablation. The system capabilities were tested on water- and gelatin- phantoms which consisted of non-uniform structure to better simulate biological tissue. A novel framework for longitudinal studies of the thyroid was subsequently developed for US monitoring of suspicious thyroid nodules. The system integrates RGB-D camera and US transducer and allows supervised US acquisitions. This robotic solution overcomes the inconsistency introduced by the human factor during acquisition of US images, and solve a common clinical problem, where the diagnosis of suspicious thyroid nodules solely depends on hand-held US images acquired over a long span of time (up to a couple of years). The system was tested on a group of volunteers. The study was approved by the Institutional Review Board (IRB-U.S.A.), and conducted with the supervision of medical expert. The results of this study proved the potential practical impact of the framework and its applicability. The second part of this thesis shows initial results for the integration of a US-guided flexible needle steering robot. A 2 degree-of-freedom robotic platform, equipped with force sensor at the needle base, is able to acquire US images with Impedance/Force control, compound three-dimensional US volumes, and perform duty-cycling flexible needle insertion. Automation communication protocol based on EtherCAT was also established. Finally, a teleoperated framework equipped for haptic feedback allowed the preliminary test for transatlantic ultrasound acquisitions. All the systems were specifically designed to perform complex tasks of manipulation on the difficult environment such as biological tissue, in a clinic scenario.