Abstract:In this paper a surgical robotic device is described that is able to discriminate tissue interfaces and other controlling parameters ahead of the drill tip. The advantage in surgery is that tissues at interfaces can be preserved. The smart tool detects ahead of the tool point and is able to control interaction with respect to the flexing tissue to avoid penetration or to control the extent of protrusion with respect to the position of the tissue. For surgical procedures where precision is required the tool offers significant benefit. To interpret drilling conditions, and conditions leading up to breakthrough at a tissue interface, a sensing scheme is used that discriminates between the variety of conditions posed in the drilling environment. The result is a fully autonomous system able to respond to tissue type, behaviour and deflection in real-time. The system is also robust in terms of disturbances encountered in the operating theatre. The device is pragmatic. It is intuitive to use, efficient to set up and uses standard drill bits. The micro-drill has been used to prepare cochleostomies in theatre and was used to remove bone tissue leaving the endosteal membrane intact. This has enabled preservation of sterility and the drilling debris to be removed prior to insertion of the electrode. It is expected that this technique will promote preservation of hearing and reduce the possibility of complications. The paper describes the device (including simulated drill progress and hardware setup) and the stages leading up to use in theatre.

Our experiments have revealed that controlling the force of drilling during cochleostomy formation and opening the endosteal membrane with a pick will minimize the trauma sustained by the cochlea by a factor of 20. Additionally, the smart micro-drill can safely perform a bony cochleostomy in humans under operative conditions and preserve the integrity of the underlying endosteal membrane.

this paper presents the novel design of an optical shape sensing method using optoelectronic sensors, for integration into flexible soft robotic manipulators, to measure pose in two orientations. Shape sensing in soft robotic tools that allow stable and accurate position control in Minimally Invasive Surgery is critical, although innovations are yet to be explored in a simple, cost-effective sensing technique. Presented in this work is a continuation of the work of Koh et.al [1], with demonstration of the use of a designed 4-plate tendon-actuated flexible manipulator and optimised design parameters for the sensing principle. Developed calibration platform shows an increase in accuracy for shape sensing using linear and non-linear regression models. Further development is required on miniaturisation to refine accuracy and targeted application.

Background There is a need for sensor-guided robotic devices that discriminate working conditions and media, and control interaction of tool-points with respect to tissues. At the micro-surgical scale the need is to control exact penetration through flexible tissues and to control relative motion with respect to moving or deforming tissue targets and interfaces.

The concept of a hand guided robotic drill has been inspired by an automated, arm supported robotic drill recently applied in clinical practice to produce cochleostomies without penetrating the endosteum ready for inserting cochlear electrodes. The smart tactile sensing scheme within the drill enables precise control of the state of interaction between tissues and tools in real-time. This paper reports development studies of the hand guided robotic drill where the same consistent outcomes, augmentation of surgeon control and skill, and similar reduction of induced disturbances on the hearing organ are achieved. The device operates with differing presentation of tissues resulting from variation in anatomy and demonstrates the ability to control or avoid penetration of tissue layers as required and to respond to intended rather than involuntary motion of the surgeon operator. The advantage of hand guided over an arm supported system is that it offers flexibility in adjusting the drilling trajectory. This can be important to initiate cutting on a hard convex tissue surface without slipping and then to proceed on the desired trajectory after cutting has commenced. The results for trials on phantoms show that drill unit compliance is an important factor in the design.