Dynamic active constraints for robot assisted minimally invasive surgery

In the past decade, the control concept of Virtual Fixtures (VFs) and Active Constraints has attracted significant research interest for robot assisted Minimally Invasive Surgery (MIS). It has also demonstrated its clinical potential of enhanced surgical safety by imposing kinaesthetic force feedback and virtual immobilisation on instrument manipulation. In situ effective guidance of access routes to the target anatomy by avoiding inadvertent damage to critical structures can be implemented by using pre-operative imaging data. Thus far, the clinical application is only well established for orthopaedic procedures, which are conducted on the relatively rigid anatomy. With recent advances in intra-operative imaging, we propose spatial constraints that are adaptive to tissue deformation in real time. These constraints define safe manipulation margins for an entire robot inside the body rather than just its end-effector in soft tissue surgeries. An analytical framework is proposed to improve robotic manipulation in image-guided surgery. This enables the operator to perform smooth articulation or steady navigation even under rapid tissue deformation. The challenges induced by kinematic redundancy of a flexible articulated robot and increased computational burden of real-time haptic rendering are addressed. Furthermore, the use of a gaze contingent paradigm is also investigated to enhance the human-robot interaction by linking the manipulation constraints with visual track. About the Speaker Ka-Wai Kwok received his BEng and MPhil degree in Automation and Computer-aided Engineering from The Chinese University of Hong Kong (CUHK). In 2007, he pursued his PhD at Imperial College London with full scholarships awarded by Pui Hua Education Foundation Committee, EPSRC and Department of Computing in the college. His PhD was supervised by Prof. Guang-Zhong Yang, in the Hamlyn Centre for Robotic Surgery. Currently, he is working as a postdoctoral research fellow in the same centre. His research focuses on image-guided robotic surgeries and their associated human-robot interface. He first proposed the constrained motion control for an articulated flexible robot used in image-guided soft tissue procedures. With the objective to bridge the basic science and clinical practice, he has interdisciplinary experience of working and co-authoring with many clinicians in validation of newly proposed surgical interfaces. Apart from academic publications, he is also keen on teaching and sharing research experiences with engineering students. He obtained two Excellent Tutor Awards sequentially in 2003 and 2004 when he was in CUHK.