医疗辅助机器人发展趋势

Feature articleRobots in healthcareRobert BogueOkehampton,UKAbstractPurpose–This paper aims to review of the use of robots in two healthcare applications:surgery and prosthetics.Design/methodology/approach–Following a brief introduction,this paperfirst considers robotic surgery and discusses a selection of commercial products,applications and recent technological advances.It then considers recent developments in robotic prosthetics.Findings–It is shown that surgical robots are being employed in an ever-growing range of clinical procedures.Systems employing tactile feedback are under development.Improved robotic prosthetics are the topic of a major research effort and recent developments include hands and grippers,walking aids and novel control techniques,including thought-activated systems which exploit advances in brain-computer interface technology. Originality/value–This paper provides details of recent developments and applications of robotic surgery and prosthetics.Keywords Robotics,Health care,Surgery,Prosthetic devices,User interfacesPaper type Technical paperIntroductionHealthcare is a robotic application which is growing due to demographic changes(an ever-growing elderly population), anticipated shortages of healthcare personnel,expectations for improving the quality of life for the elderly,the injured and the disabled and the need for even higher quality care,such as precision surgery and advanced prosthetics.These factors are stimulating the development and application of healthcare robotics and this article reviews two specific applications: surgery and prosthetics.Surgical robotsRobot-assisted surgery was originally developed to overcome certain limitations of minimally invasive procedures.Instead of directly moving the instruments,the surgeon uses a computer console to manipulate instruments attached to multiple robotic arms.The computer translates the surgeon’s movements into actions which are performed on the patient by the robot. Major advantages of robotic surgery are precision,smaller incisions,decreased blood loss,less pain and quicker recovery time.The world’sfirst surgical robot was the“Arthrobot”, which was developed and used for thefirst time in Vancouver, Canada in1983.Since then,numerous products have been developed and the best known today is the da Vinci Surgical System produced by Intuitive Surgical,Inc.(for example see Bloss,R.,Y our next surgeon could be a robot,38(1)).This comprises three components:a surgeon’s console,a patient-side robotic cart with four arms manipulated by the surgeon (one to control the camera and three to manipulate instruments),and a high definition3-D vision system. Articulated surgical instruments are mounted on the robotic arms which are introduced into the body through cannulas. This system has been used in all manner of clinical procedures and in1998it was employerd to perform thefirst robotic heart by-pass at the Leipzig Heart Centre in Germany.Robot-assisted hysterectomies and cancer staging are now being performed with the da Vinci system.Robotic neurosurgery is now a reality;history was made on12 May2008when the neuroArm robotic system(Figures1and2) operated on a human patient at the Faculty of Medicine, University of Calgary,Canada.This was thefirst time a robot had been used to perform image-guided neurosurgery and removed a brain tumour,an egg-shaped olfactory groove meningioma,from a21-year-old patient.NeuroArm operates in conjunction with real-time magnetic resonance imaging (MRI),providing surgeons with unprecedented levels of detail and control,enabling them to manipulate tools at a microscopic scale.The system comprises two robotic arms,each with six degrees of freedom,and a third arm equipped with two cameras providing3-D stereoscopic views.It allows updated MRI to be obtained during all phases of an operation(pre-,post-and intra-operative)without moving the patient.Working with a specialised set of tools,the robot is designed to perform soft tissue manipulation,needle insertion,suturing,tissue grasping,cauterising and cutting,manipulation of a retractor, suction and irrigation.The neuroArm was the brainchild of Dr Garnette Sutherland from the University of Calgary and was developed in collaboration with MDA,a Canadian robotics specialist.An improved version of the original robot,“neuroArm II”,is presently under development. Neurosurgical procedures are also the main application for the“neuromate”robot produced by Renishaw plc.This is a standard multi-axis robot which is used for electrode implantation procedures for deep brain stimulation,stereo electroencephalography(EEG)and motor cortex stimulation. Other uses include the implantation of catheters for cell grafts, drug delivery and radiotherapy.The current issue and full text archive of this journal is available at /0143-991X.htmIndustrial Robot:An International Journal38/3(2011)218–223q Emerald Group Publishing Limited[ISSN0143-991X][DOI10.1108/01439911111122699]218Surgeons feel the forceA major limitation of existing surgical robots is the lack of tactile feedback which can result in,for example,excessively tight or loose sutures.However,in 2010researchers from EindhovenUniversity of T echnology unveiled Sofie,the “Surgeon’s Operating Force-feedback Interface Eindhoven”robot which features force feedback applied to the operator’s joysticks (Figures 3and 4).The greater the applied presure,the greater Figure 1Dr Garnette Sutherland with the neuroArm roboticsystemSource: Courtesy of the University of CalgaryFigure 2Close-up of theneuroArmSource: Phil Crozier, courtesy of the University of CalgaryFigure 3The prototype Sofie medical robot is the first to feature tactilefeedbackSource: Eindhoven University of TechnologyFigure 4Linda van den Bedem beside the SofierobotSource: Eindhoven University of Technology219the resistance felt on the joysticks.This was developed as part of a PhD project by Linda van den Bedem and is thefirst surgical robot to incorporate this type of feedback,which has been patented.Sofie is also more compact than most surgical robots and is mounted on the operating table instead of thefloor, meaning that when the table is tilted or moved,the robot will move with it,so no readjustments are necessary.At present, van den Bedem and colleagues are exploring Sofie’s commercial potential but while surgeons are very enthusiastic about the prototype,the price must be considerably less than that of existing robots such as the da Vinci,which costs about $1.5million.The researcher expects that it will take aroundfive years before the Sofie can be taken to market.Achieving force feedback is attracting growing interest and recent research led by a team from the Rensselaer Polytechnic Institute involves the development of a touch-sensitive virtual reality simulator that will realistically replicate how performing a gastric band operation feels,making it ideal for developing and teaching fundamental surgical skills and also for assessing physicians wishing to be certified as a laparoscopic surgeon.The system will feature laparoscopic tools that will be connected to equipment similar to that used in actual surgical situations. The monitor will display computer-generated models on the simulation screen and the user will interact with the simulation by vision and touch.The haptics technology will help the user to experience how cutting and stitching real tissue feels. Radiosurgery and robotic guidanceRobotic systems are now being used for radiosurgery. An example is the CyberKnife(Figure5),produced by Accuray,Inc.the world’sfirst and only robotic radiosurgery system designed to treat tumours non-invasively throughout the body.It is a frameless robotic system and was invented by John R.Adler,a Stanford University Professor of neurosurgery and radiation oncology and Peter and Russell Schonberg of Schonberg Research Corporation.The two main elements of the system are the radiation source and a KUKA robotic arm which allows the source’s energy to be directed at any part of the body,from any direction.The source is a compact, 6-mV X-band linac(linear particle accelerator)which is capable of delivering high doses of radiation with sub-mm accuracy.The robotic mobility of the CyberKnife system enables the delivery of a large number of non-isocentric,non-coplanar beams,individually directed at unique points within the intended target.This facilitates frameless treatment and eliminates the need to reposition the patient for each beam. Managing respiratory motion is one of the most significant challenges in radiation treatment delivery.While most other systems employ motion-compensation techniques such as gating or breath-holding,the company’s latest product,the CyberKnife VSI System,intelligently tracks respiratory motion in real-time and automatically adapts to changes in the patient’s breathing pattern.The company’s“Iris”variable aperture collimator,based on two offset banks of six prismatic tungsten segments,allows the rapid manipulation of the beam geometry to deliver up to12beam sizes from each linac position with characteristics virtually identical to that offixed circular collimators.The delivery of multiple non-coplanar beams enhances dose conformality and creates very steep dose gradients,reducing the dose to surrounding structures.A miniature,high-precision hexapod robot with six degrees of freedom is being used to assist guidance in spinal surgery. The bone-mounted system,SpineAssist(Figures6and7),can accurately guide the surgeon to achieve maximum precision when placing implants to stabilise spinal(vertebrae)fusions in both open and minimally invasive surgery.Apart from the miniature hexapod,the system also consists of preoperative planning software with automaticfluoroscopic and CT image processing and a set of rigid bonefixing clamps and platforms.Figure5The CyberKnifesystem Source: Accuray, Inc.Figure6The SpineAssistsystemSource: Mazor Robotics LtdFigure7Close-up of theSpineAssistSource: Mazor Robotics Ltd220The hexapod measures50mm in diameter and80mm in height and weighs250g.The overall system accuracy and repeatability is less than100m m and10m m,respectively,and the motion control accuracy is10m m.Thesefigures are achieved through the use of high precision brushless DC motors,miniature lead screws and seven LVDT position sensors.SpineAssist positions its arm in the trajectory planned by the surgeon,pinpointing the exact location of the implant and the surgeon then drills and places the implant with2.5 times more accuracy than by freehand positioning and with51 times less radiation exposure from the CT scans.The SpineAssist system and the associated surgical procedures were developed by Mazor Surgical T echnologies,now Mazor Robotics Ltd,which was established in2001as a spin-off from the Israel Institute of T echnology.Robotic prostheticsProsthetic limbs have been the topic of a major research effort for many years,reflecting the desire to impart greater mobility to the disabled and the aged and also to assist in the rehabilitation of injured military personnel.Several robotic prosthetic limbs such as hands,arms and feet have been discussed in previous issues of this journal and the majority are complex electromechanical systems featuring a multitude of sensors,mechanical joints and actuators.Now,however,some groups are investigating less complex approaches and an example is research at Y ale and Harvard Universities.A group at Y ale’s Grasping and Manipulation,Rehabilitation Robotics and Biomechanics(GRAB)Lab has built a novel,four-fingered robotic hand which uses only a single actuator for the eight joints yet is able to adapt their weight passively to large variations in object geometry(Figure8).The hand is constructed using polymer-based shape deposition manufacturing(SDM),with joints formed by elastomericflexures and actuators and sensors embedded in tough,rigid polymers.SDM is an emerging manufacturing technique whereby the rigid links and compliant joints of the gripper are created simultaneously.This eliminates metal bearings,seams and fasteners that are often the source of mechanical failure.Experimental work with the prototype hand showed that even with only three positioning degrees of freedom and open-loop control,objects with a large range ofsizes,shapes and mass could be reliably grasped.This work has begun to change the way researchers approach the problem of robot grasping and may ultimately yield prosthetics which are lighter and more reliable than existing devices.Another novel approach to the gripping problem was reported by a group from the universities of Chicago and Cornell,together with iRobot Corp.,an MIT spin-off,in2010.They have created a “universal gripper”that uses the jamming of particulate material inside an elastic bag to hold objects.The gripper uses the same phenomenon that makes a vacuum-packed bag of ground coffee sofirm;in fact,ground coffee worked very well in the device.The researchers placed the elastic bag against a surface and then removed the air from it,solidifying the ground coffee inside which formed a tight grip.When air is returned to the bag,the grip relaxes.Three separate mechanisms contribute to the gripping force:friction,suction and interlocking.This gripping effect requires no sensory feedback and it was found that volume changes of less than0.5per cent are sufficient to grip objects reliably and hold them with forces exceeding their weight by many times.Some companies are now developing robotic systems that aim to overcome the mobility limitations of wheelchairs,by restoring the user’s ability to walk.For example,the Rex(robotic exoskeleton),launched in2010by Rex Bionics of New Zealand,is a pair of robotic legs that enables the user to stand up and walk with their arms free,move sideways,turn around and go up and down steps.It is suitable for wheelchair users who are capable of self-transfer and the use of a joystick.The unit is stabilised by a gyroscopic system,powered by a rechargeable battery which gives around2h of active use and weighs approximately38kg(Figure9).Eight spinal cord injury patients and one with muscular dystrophy have used the Rex experimentally.A somewhat similar system is the ReWalk (Figure10),produced by the Israeli company Argo Medical T echnologies Ltd This is also at the clinical trial stage and again uses battery power but at,15kg it is far lighter than the Rex.Fabricated from composite materials,it consists of a backpack, an upper body harness and leg supports that arefitted with motorised knees and hips.The wearer,who must have the use of their upper body,controls the movement of the leg supports Figure8The Yale/Harvard robotic hand(a)(b)Notes: (a) The complete arm and hand; (b) the gripper in actionSource: Dollar and Howe (2010)221with crutches,while motion sensors connected to a backpack computer let the device know when a step should be taken.The ReWalk is expected to go on the market in 2011.Control by thoughtThese two devices are more correctly termed exoskeletons rather than prosthetics and both use quite rudimentary control mechanisms (a joystick and upper body motion)but in the case of true prosthetics,which replace rather than augment a limb,improved mechanisms are required.This is one of the key objectives of research funded by DARPA,the US Defence Advanced Research Projects Agency,which has been working on control technologies for several years as part of its Revolutionising Prosthetics Programme.The ultimate aim is to achieve control by thought and a team at Johns Hopkins University,who were responsible for much of DARPA’s earlier prosthetic progress,received a $34.5million contract from the agency in 2010to manage the next stages of the project.The researchers will test the Modular Prosthetic Limb,which is an upper and lower arm and hand,on a human.The test subject’s thoughts will control the arm,which offers 22degrees of motion,including independent movement of each finger,and provides feedback that essentially restores a sense of touch.It weighs around nine pounds and will rely on micro-arrays implanted into the subject’s brain that record signals and transmit them to the device.The project partners include the University of Pittsburgh and the California Institute of T echnology,for their experience in brain-computer interface(BCI)technology;the University of Chicago,for its expertise in sensory perception;the University of Utah,for its capabilities in developing implantable devices suitable for interfacing with the human brain;and HDT Engineered T echnologies,for its skill in building prosthetic limbs.Within a year,the JHU-led team will begin testing the system with spinal cord injury patients.However,all existing methods to extract human neural information are inadequate for high performance prostheses,because either the level of extracted information is too low (,500events/s)or the functional lifetime is too short (,2years).Recent technological advances present new opportunities to solve both of these limitations.It is now feasible to develop tissue-response-mitigating implanted cortical microelectrodes which can extend interface lifetime well beyond two years and toward the lifetime of the patient.Other recent advances that are expected to solve these issues include high resolution peripheral neuromuscular interfaces,high-density electrocorticography arrays and tissue-engineered biotic/abiotic interfaces.These technologies are being investigated by a new DARPA programme “Histology for interface stability over time”.Some clues to the possible future direction this technology may take can be gained from the broader field of BCI technology.Reflecting the problems associated with brain implants,several BCI groups are investigating non-invasive means of thought detection,most notably EEG.Some companies have already commercialised rudimentary EEG-based BCI systems which translate thoughts into simple computer commands and the control of roboticFigure 9The Rex lower limbexoskeleton Source: Colleen Tunnicliff/Rex Bionics LtdFigure 10TheReWalkSource: Argo Medical Technologies Ltd222prosthetics is frequently cited as a major,future application of BCI technology.In2009,Honda demonstrated that its humanoid ASIMO robot could be controlled to a limited degree by the operator’s thoughts.The experimental system combines EEG with near-infrared(NIR)spectroscopy and the operator wears a helmet featuring NIR and EEG sensors which monitor and decode electrical brainwaves and cerebral bloodflow.An alternative approach to achieving improved control may result from research into“neurophotonics”.In2010the Southern Methodist University’s Neurophotonics Research Centre announced that it is leading a DARPA-funded project to develop an optical link,compatible with living tissue,that will connect powerful computer technologies to the human nervous system through hundreds or perhaps thousands of sensors embedded in a single opticalfibre.Unlike metal nerve interfaces,opticalfibres would not be rejected or destroyed by the body’s immune system.The brain will be able to both send and receive signals from a prothetic limb,thus giving amputees the ability to function normally.The Centre brings together researchers from Vanderbilt University,Case Western Reserve University,the University of T exas at Dallas and the University of North T exas.The Center’s industrial partners include Lockheed Martin,Plexon,Texas Instruments, National Instruments and MRRA.The research builds on partner Universities’recent advances in light stimulation of individual nerve cells and new,extraordinarily sensitive optical sensors being developed at SMU.Professor Volkan Otugen, SMU Director for the Center has pioneered research intosensors which utilise“whispering gallery mode”(WGM) resonators.The dielectric resonators are high optical quality polymeric spheres and the measurement principle is based on the detection of extremely small sphere deformations by monitoring the corresponding optical WGM shifts.ConclusionsBoth of the applications considered here illustrate well the contribution that robotics is making to improve healthcare.It is inevitable that robotic systems will play a growing role in the future as the fruits of research,which is progressing on a number of fronts,reaches the market.Robot-assisted surgery will expand as new capabilities and procedures are developed and it is likely that,within the forseeable future,ever more capable prosthetics,including thought-controlled devices,will become a reality.ReferenceDollar,A.M.and Howe,R.D.(2010),“The highly adaptiveSDM hand:design and performance evaluation”,International Journal of Robotics Research,Vol.29No.5,pp.585-97.Corresponding authorRobert Bogue can be contacted at:robbogue@223T o purchase reprints of this article please e-mail:reprints@ Or visit our web site for further details:/reprints。