Co-Planar Stereotaxic Atlas of the Human Brain—3-Dimensional Proportional System: An Approach to Cerebral Imaging, J. Talairach, P. Tournoux. Georg Thieme Verlag, New York (1988), 122 pp., 130 figs. DM 268

In this paper, we describe the state of the art in continuum robot manipulators and systems intended for application to interventional medicine. Inspired by biological trunks, tentacles, and snakes, continuum robot designs can traverse confined spaces, manipulate objects in complex environments, and conform to curvilinear paths in space. In addition, many designs offer inherent structural compliance and ease of miniaturization. After decades of pioneering research, a host of designs have now been investigated and have demonstrated capabilities beyond the scope of conventional rigid-link robots. Recently, we have seen increasing efforts aimed at leveraging these qualities to improve the frontiers of minimally invasive surgical interventions. Several concepts have now been commercialized, which are inspiring and enabling a current paradigm shift in surgical approaches toward flexible access routes, e.g., through natural orifices such as the nose. In this paper, we provide an overview of the current state of this field from the perspectives of both robotics science and medical applications. We discuss relevant research in design, modeling, control, and sensing for continuum manipulators, and we highlight how this work is being used to build robotic systems for specific surgical procedures. We provide perspective for the future by discussing current limitations, open questions, and challenges.

Continuum Robots for Medical Applications: A Survey

Small-scale soft continuum robots capable of active steering and navigation in a remotely controllable manner hold great promise in diverse areas, particularly in medical applications. Existing continuum robots, however, are often limited to millimeter or centimeter scales due to miniaturization challenges inherent in conventional actuation mechanisms, such as pulling mechanical wires, inflating pneumatic or hydraulic chambers, or embedding rigid magnets for manipulation. In addition, the friction experienced by the continuum robots during navigation poses another challenge for their applications. Here, we present a submillimeter-scale, self-lubricating soft continuum robot with omnidirectional steering and navigating capabilities based on magnetic actuation, which are enabled by programming ferromagnetic domains in its soft body while growing hydrogel skin on its surface. The robot's body, composed of a homogeneous continuum of a soft polymer matrix with uniformly dispersed ferromagnetic microparticles, can be miniaturized below a few hundreds of micrometers in diameter, and the hydrogel skin reduces the friction by more than 10 times. We demonstrate the capability of navigating through complex and constrained environments, such as a tortuous cerebrovascular phantom with multiple aneurysms. We further demonstrate additional functionalities, such as steerable laser delivery through a functional core incorporated in the robot's body. Given their compact, self-contained actuation and intuitive manipulation, our ferromagnetic soft continuum robots may open avenues to minimally invasive robotic surgery for previously inaccessible lesions, thereby addressing challenges and unmet needs in healthcare.

Ferromagnetic soft continuum robots

IEEE International Conference on Robotics and Automation (ICRA) におけるフルードパワー技術の研究動向

https://www.jstage.jst.go.jp/article/jsprs1975/37/6/37_6_39/_pdf

1998 IEEE International Conference on SMCに参加して

Background

Remote-controlled catheter navigation systems have recently been introduced into minimally invasive vascular surgery and some of them have already been applied in clinical practice. Steerable catheters with improved manoeuvrability play an important role in these innovations for conventional catheterization.



Methods

This review details the development of various steerable catheters, both in use clinically and under investigation. Comprehensive comparison and analysis in several key aspects are followed to reveal both the advantages and limitations of these catheters, as well as the requirements for relevant techniques.



Results

Steerable catheters are able to select direction in the distal end, and superior to conventional counterparts in many aspects. Differences between magnetic and active catheters mainly lie in function, safety, configuration of operating room and cost. They have similar requirements for miniaturization and slave insertion mechanisms.



Conclusions

Steerable catheters are rapidly evolving and still require technological refinements to extend current capabilities. Copyright © 2009 John Wiley & Sons, Ltd.

Steerable catheters in minimally invasive vascular surgery.

This paper proposes a master-slave catheterisation system including a steerable catheter with positioning function and an insertion mechanism with force feedback. The steerable catheter is integrated with two magnetic tracking sensors for positioning. The distal shape of catheter is displayed with virtual vascular model to generate 3D guiding image to provide the relative relationship between the catheter and its surrounding vessels. The master-slave insertion mechanism with differential gear structure is designed with force feedback to assist surgeons to manipulate the catheter. It can implement pulling/pushing, rotating and bending/recovering the catheter. Based on this system, surgeons in the control room can utilise the master handle to operate the insertion mechanism for positioning the distal end of catheter with the assistance of 3D guiding image. The stability and accuracy of the system is validated in-vitro.

The master-slave catheterisation system for positioning the steerable catheter

This paper presents a novel upper extremity motor function rehabilitation system and an assessment system. The rehabilitation system is an active rehabilitation that can be manipulated by patients through a haptic device and an inertia sensor to perform a tracking task in virtual environment with coordination training of bilateral upper extremity. The design of system aims to augment patients' force exerted by their upper extremity and the ability of force control, namely, dexterity. The structure of rehabilitation system is compact and the inertia of the haptic device's stylus is very small (only 45 g), which makes the system suitable for home-rehabilitation. Simultaneously, in order to assess the effect of rehabilitation, an assessment system has been developed using a 6-axis force sensor. The proposed rehabilitation system is testified experimentally for the upper limbs' rehabilitation training.

Development of an upper extremity motor function rehabilitation system and an assessment system

Human hand is easy to be injured. As physical rehabilitation therapy after a hand operation always takes a long time, the curative effect gets worse and the social and financial hardship with physical deterioration can be caused. A CPM machine is a mechanism based on the rehabilitation theory of continuous passive motion (CPM). To improve rehabilitation results and validate the CPM theory we have developed a portable exoskeleton based CPM machine. The device can be easily attached and also be adjusted to fit different hand sizes. And during the finger's flexion and extension motion the machine can always exert perpendicular forces on the finger phalanges. It can achieve the precise control of scope, force and speed of the moving fingers. Finally based on its mechanical structure, a kinematic validation and simulation including kinematic simulation and dynamic simulation have been carried out.

Design and development of a portable exoskeleton based CPM machine for rehabilitation of hand injuries

Background

Robot-assisted systems have been widely used in minimally invasive surgery (MIS) practice, and with them the precision and accuracy of surgical procedures can be significantly improved. Promoting the development of robot technology in MIS will improve robot performance and help in tackling problems from complex surgical procedures.



Methods

A medical robot system with a new mechanism for MIS was proposed to achieve a two-dimensional (2D) remote centre of motion (RCM). An improved surgical instrument was designed to enhance manipulability and eliminate the coupling motion between the wrist and the grippers. The control subsystem adopted a master–slave control mode, upon which a new method with error compensation of repetitive feedback can be based for the inverse kinematics solution. A unique solution with less computation and higher satisfactory accuracy was also obtained. Tremor filtration and trajectory planning were also addressed with regard to the smoothness of the surgical instrument movement.



Results

The robot system was tested on pigs weighing 30–45 kg. The experimental results show that the robot can successfully complete a cholecystectomy and meet the demands of MIS.



Conclusions

The results of the animal experiments were excellent, indicating a promising clinical application of the robot with high manipulability. Copyright © 2011 John Wiley & Sons, Ltd.

Yili Fu

Papers

Steerable catheters in minimally invasive vascular surgery.

The master-slave catheterisation system for positioning the steerable catheter

Development of an upper extremity motor function rehabilitation system and an assessment system

Design and development of a portable exoskeleton based CPM machine for rehabilitation of hand injuries

Development of a medical robot system for minimally invasive surgery