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					                                                            `Robotics for medical applications



 1. INTRODUCTION

       The application of robots or more generally of technologies and know-how derived
from robotics research – to medicine has moved rapidly in the last few years from the
speculation of a small group of "visionary" scientists to reality. Today, robotics can be
considered as a real opportunity, available to operators in the medical field, as well as to
industries which want to explore a market that can quickly become very attractive. The
growth of interest on medical applications of robotics has been so rapid recently, that it is
already difficult to provide a "still" picture of this field. There is a classification that may be
helpful as a guideline to discuss the main applications and perspectives of robotics in
medicine. Medical robots are one of the most helpful applications of robots. They are used in
various medical practices, including difficult and precise surgical procedures. They are also
used to assist patients in recovery and in the performance of routine tasks for patient care.
Medical robots have computer-integrated technology and are comprised of complicated
programming languages, controllers, and advanced sensors. They also possess powerful
control units, a programming terminal, and process-oriented software for various medical
applications.


       Medical robots are used for training surgeons and providing in-depth knowledge to
students. These robots provide standardized operation, which reduces the time required to
perform any medical operation. They provide positional certainty and confined movement,
which can lead to improved post-operative outcomes. The major potential advantages of
medical robots are precision and miniaturization in medical operations. Further advantages
are articulation beyond normal manipulation and three-dimensional magnification. Doctors
can view the patient, ask questions, read patient records, view X-rays, and test results using
these robots. Although the robot does not physically examine the patient it, allows face-to-
face contact between the doctor and patient with the help of a screen attached to it. They are
also used inward rounds when doctors are away from patients, which allow patients to
establish direct contact with doctors. Research is going on in the field of medical robotics that
will create new robotic technologies and benefit the healthcare industry. The use of WiFi
technology in the medical robots allows a medical expert to visually examine and
communicate with a patient from anywhere in the world.
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       There are many doctors, who are using medical robotic technologies in their regular
clinical practice. Doctors believe that it is a revolutionary concept, which opens new avenues
for telemedicine research and integrates technology with healthcare while establishing
necessary interface between patients, clinicians, and teaching staff.

       Rather than trying to enumerate all the possible different applications of robots or
robotics technologies to medicine, we have identified three main areas of robotics which
considered the most promising directions for the evolution of the state-of-the-art of
technology in medicine. These are: macro-robotics, micro-robotics and bio-robotics. Macro
robotics includes the development of robots, wheelchairs, manipulators for rehabilitation as
well as new, more powerful tools and techniques for surgery; micro-robotics could greatly
contribute to the field of minimally invasive surgery as well as to the development of a new
generation of miniaturized mechatronics tools for conventional surgery; bio-robotics deals
with the problems of modeling and simulating biological systems in order to provide a better
understanding of human physiology. Since robots are used mainly in manufacturing, we see
their impact in the products we use every day. Ususally this results in a cheaper product.
Robots are also used in cases where it can do a better job than a human such as surgery where
high precision is a benefit. And, robots are used in exploration in dangerous places such as in
volcanos which allows us to learn without endangering ourselves.

       This general classification reflects the fact that, from the medical point of view, robots
can certainly find practical application in two main fields: surgery and residential care.




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2.ROBOTICS FOR SURGERY

       Many different projects in the field of robotics for surgery have been carried out
during the last ten years, and few of them already generated industrial systems that are
currently under clinical evaluation in hospitals. Somewhere in the “middle” is an area also
very interesting,
which some investigators refer to as “mechatronics tools for surgery.” The aim of this branch
of medical robotics is to broaden the concept of robotic devices for surgery by taking
advantage of methodologies and technologies directly derived from the state-of-the-art in
robotics. Considering the valuable progresses of the last decades in the field of micro-
mechanics and mechatronics, this approach could potentially lead to a quick and wide
diffusion into the market of innovative surgical tools and thus to clinical practice.


        The numerous applications of robotics to surgery can be classified in two main areas:
those based on “image-guidance” and those aimed at obtaining minimal “invasiveness.”


2.1 Image-guided Surgery

       The basic concept behind image-guided surgery is the use of a robot workstation
integrated into the operating theater where some of the parts of the patient‟s body are fixed by
means of suitable fittings. This scenario is easy to implement for orthopedic surgery, where
fixators are commonly used to fix bones, and also for neurosurgery, where the stereotactic
helmet, mounted on the patient‟s head, is quite popular to provide absolute matching between
pre-operative and intra-operative reference frames. Vision-based surgery may be viewed as a
robotic CAD-CAM system where diagnostic images (from CT, NMR, US, etc.) are
used for off-line planning of the intervention.The robot is used in a CNC machine tool-like
fashion for precise cutting, milling, drilling and other similar tasks. A better quality of the
intervention results from better performance of robots with respect to the manual operation of
a surgeon in terms of accuracy and repeatability. Experimental evidence of the superiority of
robot cutting versus normal cutting is illustrated in Figure 1 for the case of bone milling for
hip implant, although some problems in terms of longer duration of surgery with the robot
versus human operator, and of post-operative pain have been reported

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           Fig.1: A comparison between (a)robots (b)surgeons performance in
                     Bone milling for hip replacement


Real-time images may also be used during the intervention in combination with diagnostic
images and tool positiodorientation data in order to provide the surgeon with feedback about
the current state of the intervention. It is important to point out that the surgeon supervises the
robot system during operation. Among the obvious differences between an industrial robot
application and a surgical one, an important one is the need for suitable matching procedures
between diagnostic images and off-line intervention planning, on one hand, and real
execution, on the other hand. As mentioned before, the issue of matching has been addressed
and solved in some cases (specifically in the case of bone cutting in orthopedics), but many
problems still remain open due to the fact that most interventions on parts of the human body
involve soft tissues so that large deformations may occur. This results in possible
discrepancies between pre-operative and intra-operative images. Image-guided surgery
includes orthopedic surgery, spine surgery, neuro-surgery, reconstructive/plastic surgery and
ORL surgery. A veiy representative example of implementation of imageguided robotic
surgery is the one proposed by R. H. Taylor             which has been implemented in an industrial
system (Robodoc, ISS Inc., Sacramento, CA, USA) currently used in human trials for
automated implant of hip prostheses. The main motivation for many researchers to explore
the use of robotic devices to augment the surgeon‟s ability to perform geometrically precise
tasks is the consideration that the precision of surgical planning often greatly exceeds that of
surgical execution. The ultimate goal of this effort is a partnership between humans
(surgeons) and machines (computers and robots) that seeks to exploit the capabilities of both
to perform a task better than either can perform alone

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       The architecture of the hip replacement surgery system depicted in Figure 2 consists
of a CT-based pre-surgical planning subsystem, shown in Figure 3, and of a surgical sub-
system.




              Fig.2: A view of hip replacement surgery system in operation theatre




          Fig.3: An example for a pre operative planning procedure for the hip replacement system
    The surgical procedure includes manual guiding to approximate positions of pins, pre
operatively inserted into bones (which are fixated to the operating bed), and an automatic
tactile search for each pin. Then, the robot controller computes the appropriate transformation


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to machine out the implant cavity. Finally, the pins are removed and the surgeon proceeds in
the conventional manual procedure. Safety issues have been given major consideration. In the
“Robodoc” system they include extensive checking and monitoring of cutter force, and the
possibility for either the surgeon or the controller to freeze all robot motion or to turn off
manipulation and cutter power in response to recognized exceptions. Techniques which are
essentially similar to the one described before, but which have been adapted to been
developed for the cases of total knee arthoplasty (see Figure 4), percutaneous discectomy
spine surgery , neurosurgery, prostate surgery, and eye surgery .




             Fig.4: Knee prosthesis implant (a) before intervention (b) after intervention
                                (c) cavity due to robotic surgery


       Teleoperation, virtual reality environments and advanced Man/machine interfaces will
probably play a key role in the future of image-guided surgery. Teleoperation can be useful in
some cases, such as when a patient urgently requires an operation in a place where no
specialized surgeon is available (for example, on a battlefield or an ambulance), or when for
safety reasons (patients with infectious diseases, or long operations under X-ray) it is not
appropriate for the surgeon to be within the operation field. Another critical problem which
can be solved by means of teleoperation is the increasing requirement for room for equipment
in the neighborhood of the patient‟s bed, so that it might become nec necessary for the
surgeon to move away and operate remotely.




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                                Fig.5: Tele operated surgery



       Advanced man/machine interfaces and force replication devices might also play an
important role in the framework of intervention simulation and surgeon training carried out in
virtual environments featuring realistic 3D representations of body organs. Some examples of
interfaces possessing the sophisticated features which are required for truly realistic
simulations of surgical interventions are already existing .


2.2 Minimal Invasive Surgery

Minimal invasive surgery (MIS), also called “endoscopic surgery,” is gaining increased
acceptance as a powerful technique beneficial to the patient‟s integrity, time of recovery
and cost for assistance. At its current stage of development, MIS depends on three
prerequisites: the availability of high quality video endoscopy, the ability of high precision
surgical instruments and the manual skill of well-trained surgeons
         MIS requires accessing the organ to be operated through a small hole, and the
surgeon, although directly responsible for the manipulation of the surgical tool, misses a large
part of the information necessary to finely control the end effector. At present, MIS depends
on a sort of “craftsmanship,” where operating surgeons must compensate with their skills for

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the fact that they cannot touch and sense with their fingers for diagnostic purposes; they lack
3D view of the workspace; the access to the workspace is restricted and they cannot feel the
forces/torques and pressure they are exerting at the end effector tip. A possible scenario of the
next generation of MIS consists of a combination of tele-manipulation and tele-robotics
Technologies. Generally speaking, robotics technology can contribute to reduce the level of
surgical invasiveness in three different areas: the first is lupuroscopic surgery, which is based
on stiff tools that the surgeon manipulates directly and by which he/she can keep some (even
if small) degree of “feeling” on the features of the operational workspace; the second is
commonly referred as endoscopic surgery, which makes use of flexible endoscopes and
implies the virtual loss of any type of “feeling” for the surgeon; the third is not linked to any
specific type of surgery and consists of an attempt of improving the performances of
traditional macro surgical tools by applying mechatronic technologies aimed at decreasing
the invasiveness of tool operation. However, major development efforts are needed in such
areas of robotics technology as sensor integration, force reflection, miniaturization of
mechanisms and actuators, and control. A very challenging approach to MIS is pursued in
Japan, where the development of teleoperated micro-catheters capable of diagnostic and
surgical interventions within brain blood vessels is currently underway. The micro-catheter
will possess high dexterity at the tip and all along its length, like the macro one shown in
Figure 6, and it will also incorporate micro-fabricated tactile, flow and pressure sensors at the
tip, along with micronozzles and micropumps for local injection
of drugs and solutions for dissolving thrombus

       A very innovative approach for solving the problems encountered with present MIS
instrumentation is proposed by some investigators. This approach involves a conceptually
radical modification to the design of traditional endoscopes, by developing a microrobot for
endoscopy able to move autonomously along the colon by inchworm locomotion [as].In
Figure 6 is depicted a prototype of the microrobot.




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                                                      Fig.6.1: Example of catheter tip with
                                                             Increased dexterity




   Fig.6 :A system for brain blood vessel
            Diagnostic and surgery




                       Fig.:7 Micro-robot endoscopy




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                         Fig. 7.1: Next generation micro endoscope for MIS




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3. ROBOTICS FOR REHABILITATION

       The possible role of robotics in the field of rehabilitation has been widely investigated
in the last decades. Possible specific applicative areas which have been already identified
range from the assistance to the disabled and the elderly, by means of robotic manipulators,
intelligent wheelchairs and dedicated interfaces for household and vocational devices,
through the restoration of impaired functions, by means of advanced prostheses, ortheses and
electrical functional stimulation (FES), to the development of virtual environments for
training and genuine rehabilitative therapies. Whatever the selected approach, one of the key
factors for the success of robotic aids for the disabled is certainly the potentiality to make
these peculiar users still able to exert a complete control on their environment by using a
robotic interface.


        In rehabilitation robotics, the term “environmental control” refers to a disabled user‟s
capacity to actively interact with his or her external environment . Although all of the
sensory and motor functions are necessary for complete environmental control, disabilities
based on partial or total loss of upper limb function are particularly serious, due to the
consequent reduction in, or loss of, the manipulative function. This kind of disability is the
most significant impediment in carrying out common everyday activities (e.g. personal
hygiene, job, hobbies): the user receives the external stimuli but he or she is then unable to
respond to, or act on, them. When lower limb function is also reduced (or lost), the physical
(and psychological) loss of control is profound, and makes a disabled user dependent on
others in virtually every respect. Numerous research teams, potential users and manufactures
are already involved in developing techniques for environmental control, and for controlling
robots in the context of rehabilitation and assistance for disabled users. At present, the
ordinary use of rehabilitation technology involves a general purpose computer at the hub of a
multipurpose cockpit, and the user operates all ofhisiher (specialized oradapted) products
from that cockpit. There are some advantages to this, especially for severely disabled or bed-
ridden users, but less so for users with moderate, or age-related disabilities: the user is
distanced from the task itself, the interaction style is based on the computer, rather than on
the product being used and the task being performed. In such a context of use, and for these


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users, the computer remains an obtrusively technical device which tends to appear as the
unique link between disabled users and their environment.


3.1. Manipulators in Rehabilitation

       A primary objective of rehabilitation robotics has always been to fully or partly
restore the disabled user‟s manipulative function by placing a robot arm between the user and
the environment. Some important factors must be considered in the design of such a peculiar
environmental control system: the user‟s degree of disability (a system must be flexible
enough to be adapted to each user‟s capabilities); modularity (system inputs and outputs must
be easy to add or remove according to each user‟s needs); reliability (a system must not let
the user down); and cost (the system must be affordable).


              According to the state-of-the-art of rehabilitation robotics, three different
configurations of robot systems, differently reflecting the above mentioned factors, have been
considered as feasible for the assistance of severely and moderately disabled users.
Historically, the first configuration which has been investigated is the bench-or table-
mounted manipulator included in a completely structured desktop workstation.


              Even though various systems based on this approach were positively evaluated
with users, [3 and some commercial products already appeared on the market, such as the
DEVAR system (Tolfa Corporation, Palo Alto, CA USA) and the RAID system (Oxford
Intelligent Machines Ltd., Oxford, Great Britain), yet they seem to be mainly suitable for
assisting disabled employees for executing vocational tasks at their workplace.




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                            Fig.8: MASTER desktop workstation


       In fact, desktop workstations better reflect the type of organization of space and time
which is typical of vocational activities. Furthermore, this approach involves all the
previously discussed drawbacks of using a „cockpit‟ environmental control system. One of
the early prototypes of desktop workstation, the MASTER (Manipulator Autonomous at
service of Tetraplegia for Environment and Rehabilitation) System was developed in France
by CEA (Paris) and is shown in Figure.
                   The wheelchair-mounted arm is particularly suited to users with upper
limb disabilities, but its usefulness relies on the user being able to move (or control the
movements of) the wheelchair, so that the robot can be taken to the area(s) of activity. The
home environment must also be adapted to suit the robot‟s working height, making it an
intrusive solution. This solution, depicted in Figure 9, is becoming more popular as it allows
the disabled or elderly to use the robot arm everywhere, not being necessarily related
anymore to some fixed structured locations and is being widely experimented . However,
some technical problems, mainly concerning the accuracy which can be obtained on
grasping operations (the arm is fixed to the wheelchair which is not properly a rigid structure)
and the possibility of equipping the wheelchair with a user-friendly (and then complex)
arm controller (the available space and the battew energy are limited) have still to be solved.
All these factors seem to presently limit the perspectives for this approach to become


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economically attractive by inducing concrete market demand. Moreover, this solution does
not actually address all disabled users, but only those able to use a wheelchair.




                                      Fig.9: Wheel chair mounted arm




       As a matter of fact, in both previous cases, a severely disabled or bed-ridden user is
not well catered for: the workstation dominates the user‟s home environment, while the
wheelchair-mounted robot is simply not an option.
       A third different solution is to use an autonomous or semiautonomous mobile vehicle
equipped with a manipulator and additional sensor systems for autonomous or
semiautonomous operation. Its mobility makes it particularly suitable for severely disabled or
bed-ridden users, as long as the interface between the user and the robot is easy to use: the
user should be able to instruct the robot with a high-level language, via a bi-directional user
interface offering appropriate methods of input and suitable output. This configuration was
first used in industrial applications (e.g. textile industries) and is surely the most sophisticated
one, but it is also the most generally applicable, since the idea of having a robot in personal



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service can be attractive to both able-bodied and disabled users. An early prototype of a
rehabilitative mobile robot was developed by S.Tachi et al. at the MITI Japanese
laboratories. This system, named MELDOG, was devised only to act as a robotic “dog” for
blind patients, thus not having any possibility of manipulating or carrying objects. Generally
speaking, the ideal system should include subsystemsdedicated to vision, fine manipulation,
motion, sensory data acquisition, and system control. A sketch of a possible
configuration for such a robot is shown in Figure 10.




                                Fig.10: Concept of mobile robotic aid
The cost of this solution is often prohibitive for all but the wealthiest of users, and the
usability problems inherent in such sophisticated systems have yet to be satisfactorily
solved for non-professional users. Various prototypes of autonomous or teleoperated mobile
robots for the assistance to the disabled in different activities have been implemented
and others are currently under development
`Two ongoing research projects in this field: namely, the American MOVAR system, mainly
devised for vocational use, and the Italian URMAD system, mainly devised for residential
applications. Both prototypes have been almost completely implemented. In partic- ular, the
URMAD system (the acronym stands for “Mobile Robotics Unit for the Assistance to the
Disabled”) is being currently experimented with the final end users, i.e. severely disabled
patients, in a real application site (a nursing-home for severely disabled) in Italy.

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      Fig.11: MOVAR system                                    Fig.11.1: URMAD system




One of the main unsolved technical problems is that the more the performance of the robot is
enhanced the more its dimensions (ideally imposed by the standard building norms), its
autonomy of operation, and consequently its cost become excessive for prefiguring an
effective commercial exploitation.
 An attempt    to overcome these drawbacks and limitations is being carried out in the
framework of the TIDEMOVAID project by an European team coordinated by the
ARTS Lab of the Scuola Superiore S. Anna. As illustrated in Figure 12, the final objective of
this project is to develop a complete system, including a mobile robot, having functional
performances similar to those of URMAD but still respecting the limitations imposed by a
normal household environment, thus eliminating the need for a major adaptation of the house.




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                                  Fig.12: MOVAID appraoch




This goal is being pursued by partially distributing resources in the environment instead of
concentrating them on the vehicle. As long as the distribution of resources is well balanced
and technologies are properly integrated in the domestic environment, such a realistic
solution could represent a good compromise between the current state-of-the-art in advanced
robotics and the ideal concept of the autonomous robotic assistant in a modern domestic
scenario, thus hopefully avoring a rapid commercial exploitation. To this aim, the MOVAID
project, rather than developing new basic hardware components, will take advantage of the
results of previous research projects. The URMAD manipulator, which is being used for the
MOVAID mobile unit, is shown on the cover.
       Another important aspect of the MOVAID project is that the emphasis is in the
friendliness of the system‟s interface and on a non-intrusive integration of technologies in
thedomestic environment. For instance, a major appliance manufacturer (Philips BV)
purposely developed the concept of new products, equipped with novel friendly interfaces

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which, based on the MOVAID philosophy, are accessible to all users, including the elderly
and the moderately disabled. Severely disabled users will be catered to by special M3S1
interfaces. (1M3S is an emerging standard for technical aids for the disabled whose detailed
definition is the specific outcome of two projects (M3S and FOCUS) promoted by
theEuropean Union in the framework of the TIDE Program (Techonology Initiative for the
Disabled and the Elderly).) In this perspective, MOVAID represents a potential opportunity
to achieve a direct of advanced technologies towards the home environment. This approach,
which is strictly related to an increasing industrial interest in “idomotics” (i.e. the
development of a “smart” house accessible to all users, including the disabled and the
elderly) could also have interesting applications in the medical field (telemedicine, home
assistance vs. clinical assistance for the disabled and the elderly, etc).




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4. Robotics Systems for Hospitals
 Mobile robots could become one answer to the current shortage of help in hospitals, as well
as one solution to the problem of the diseases (lumbago, low back pain) which affects the
personnel involved in heavy physical tasks such as lifting a patient and carrying him/her to
the toilet, or relatively “unpleasant tasks,” such as changing sheets in the bed of an
incontinent patient.
       An example of implementation of a hospital transport mobile robot has been presented
recently by Transition Research Corporation (now Helpmate Robotics, Danbury, CT, USA).
The robot, shown in Figure 13, has been designed and built for addressing the need for
assistance with such tasks as point to point delivery.




                   Fig.13: The Helpmate hospital transport mobile robot




The objective of the hospital transport mobile robot (“HelpMate”) is to carry out such tasks
as the delivery of offschedule meal trays, lab and pharmacy supplies and patient records. The
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navigation system of the HelpMate, unlike many existing delivery system in the industry
which operate within a rigid network of wires buried or attached to the floor (“AGVs”), relies
on sensor-based motion planning algorithms that specifically address the issue of navigation
in a partially structured environment. The system is also able to handle sensor noise and
sensor inaccuracy, errors in position estimation, and moving obstacles(eg:people)
          Help Mates have been installed in several hospitals. In some hospitals HelpMate is
in operation 24 hours per day and the hospitals are reporting an increase in productivity and
efficiency. The HelpMate represents a useful and probably industrially valuable solution to
some basic needs requiring the transportation of lightweight objects. The complexity of the
system is deliberately kept low by eliminating automated manipulation (which is carried out
by human operators), by assuming flat floor in the working environment (the robot uses
elevators - which are controlled by means of elevator control computers activated by an
infrared transceiver-, and doors), and by providing the robot with accurate geometric and
topographical information about the hospital hallways, elevator lobbies and elevators.
       It is worth noting that the European Union has recently funded a novel action,
promoted by the ARTS Lab of the Scuola Superiore Sant„Anna, in the framework of the
Technology Innovation Programme VALUE. In this new project, named HOSPIMAID, the
URMAD platform is being further developed specifically for hospital applications.
            Different types of help to nurses could be provided by heavier robots, designed to
execute tasks requiring hard muscular work. Japanese laboratories and industries have
identified this field as very promising, and have invested substantial efforts in the
development of fetch and carry robots for hospitals, usually hydraulically actuated and
featuring by high payloads. An interesting example of such type of robot is the patient care
robot named “MELKONG,” that was developed a few years ago by the Mechanical
Engineering Laboratory (MEL) in Japan . The MELKONG was intended to lift, hold and
carry an adult patient (weighing up to about 100 kg) or a disabled child. The robot docked to
the bed in the hospital room, lifted the patient in its arms from the bed, moved back still
holding him/her in its arms and transferred him/her to the toilet, or bathroom, or dining room.
Usually, the robot was controlled by a nurse, but it was expected that at night the patient could
also call the robot and control it by means of simple commands given through a joystick.
Serious problems related to automatic docking, mobility, manipulation, actuation (by
hydraulic actuators), energy supply, man/machine interfaces were addressed and so.
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         The MELKONG concept has evolved from the early prototype described above to
more sophisticated versions incorporating functional and aesthetic improvements. A transfer-
carrier vehicle based on an evolution of the MELKONG concept is commercially available in
Japan.
          Furthermore, a simple functional robot aimed at supporting the elderly and the
disabled for independent living, in particular for evacuation (a function that the elderly would
really wish to do by himself or herself if adequate support equipment were available), is also
being developed in Japan jointly by the National Institute of Bioscience and Human
Technology of AIST.




             Fig.14   Mobile Robot




5. Intelligent Wheelchairs


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For a physically disabled person the main advantage of using a transport mechanism like
ordinary wheelchairs (and of the robot manipulators possibly mounted on them) a number of
approaches have been proposed based on robotics and mechatronics technologies. These
approaches comprise attempts to develop autonomous vehicles which can be used to transport
a person from one location to another with little or even without external assistance, as well
as attempts to increase the capability of the vehicle to move on unprepared surfaces and to
overcome obstacles. An example of the first approach is represented by self-navigating
wheelchairs, as the one proposed by Madarasz et al. a few years ago. The vehicle, designed to
function inside an office building, is able to plan its own path from its current location to a
particular room in the building, and then to travel to that location. The system must also
function with minimum impact on the building in which it will be used, that is the building
cannot be equipped with a guidance mechanism, such as embedded wires in the floor or
painted stripes that can be followed. Therefore, the wheelchair becomes substantially a sort of
mobile robot with high degree of autonomy. In fact, the vehicle is self-contained: all of the
sensing and decision making are performed by the on-board equipment. This approach
relieves the disabled person from tasks he/she may be unable to carry on, but a system for
supervised control is provided for high level commands and for other types of operations
requiring direct guidance. In Europe, a recent example of a project aimed at developing a
wheelchair featured by partly autonomous behavior is represented by the European TIDE-
OMNI project. An Italian manufacturer (TGR s.r.l., Ozzano Emilia, Italy) produces a
wheelchair (named “Explorer”) incorporating both wheels and tracks. This wheelchair, which
has been also modified to host the MANUS system in the framework of the European
SPRINT-IMMEDIATE project, cannot only run on regular terrain, but can also go up and
down stairs with the user on board,possible development of a new generation of vehicles
designed to deeply enhance the mobility of the user.




6. FROM ADVANCED PROSTHESES AND ORTHESES TO FES



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There have been frequent intersections between robotics and limb prosthetics technologies in
the past. Many devices, like artificial legs, artificial hands and arms, have evolved in the
„60s and „70s both as prostheses for amputees and as possible components of advanced
robots. Examples of these devices are the Belgrade hand and the UTAH arm . More recently
the UTAH-MIT dexterous hand was designed as a robotic hand by taking inspiration from
the human hand, whereas new prostheses for amputees have been developed by exploiting
last advances in robotics technology (like the three-fingered hand developed in the
framework of the European TIDE-MARCUS project). However, it is quite obvious and very
clear to all of those working in the field of aids for the disabled that, although disabled
persons may accept artificial devices as assistants, their dream and ultimate goal is to be able
to manipulate and walk again. Although this is out of reach of current medical capabilities,
a few promising approaches are being pursued by some investigators which might ultimately
render that dream closer to reality. An early example of a robotic device to help patients with
impaired walking capabilities to restore their functions is the one developed in Japan. An
evolution of the above mentioned assistive device for “natural” walking is the active orthesis,
whose development has been pioneered by Prof. Pierre Rabischong and his team.




                              Fig.15: Active orthosis: master-slave uersion


It is basically a hybrid vehicle incorporating wheels as well as two “arms” that can work both
as manipulators and as legs, is based on the assumption that a legged vehicle allows
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locomotion in environments cluttered with obstacles where wheeled or tracked vehicles
cannot be used. A legged vehicle is inherently omnidirectional, provides superior mobility in
difficult terrain or soil conditions (sand, clay, gravel, rocks, etc.) and provides an active
suspension. The legs also give the chair versatility and allow it to be re-configured. When
stationary, one of the legs can be used as a manipulator in order to perform simple tasks such
as reaching for objects or pushing. A key component for improving the performance of FES
based apparatus is the implanted electrode. Development in this field might not only lead to
obtaining better systems for computer-assisted manipulation and locomotion, but eventually
even help realize the dream of restoring natural manipulation and locomotion.




                             Fig.16: DAVANCHE Robot




7.BIO- ROBOTICS

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Biological systems are not only the recipient of the services of robots, but also the source of
inspiration for components and behaviors of future robot systems. This not well defined, but
intriguing and stimulating area of interest for robotics, can becalled “bio-robotics” and is
currently receiving an increasing amount of attention by many investigators. In general,
biological systems are a living proof that some complex functions (both sensorimotor and
“intellectual”) that robotics researchers should like to realize in artificial systems can actually
be implemented. Locomotion, manipulation, vision, touch are all functions which living
beings execute seemingly without effort, but which turned out to be extremely difficult to
replicate in artificial systems. In the recent past, many different groups have been active in
this “borderline” area where the distinction between “robotics” and “bioengineering”
becomes very subtle. A book discussing state-of-the-art result and perspectives in this field
has been published recently. Examples of components which are explicitly inspired to their
biological counterparts (and which are intended to be the “core” of sensorimotor systems
capable of replicating the function of their biological counterparts) are retina-like CCD
sensor and tactile sensors. A photograph of the CCD vision sensor, whose geometry is
inspired to the one of the human retina (including the high-acuity fovea-like central
part), is reported in Figure 17




                          Fig.17: CCD Version scanner




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A scheme of a fingertip incorporating three different types of sensors which provide (in
combination with appropriate sensorimotor acts) the robot controller with information on
object geometry and material features comparable to those of the human fingertip, is given in
Figure 17.1




                             Fig.17.1: Human Finger tip




A close-up of one of the sensors (a 256-element array sensor),which imitates the space-
variant distribution of tactile receptors in the fingertip skin, thus emphasizing the role of
“attentive behavior” in active touch, is also reported in the same figure. Further applications
in the field of bio-robotics involve the use of artificial systems as accurate models for
investigating the physiology of biological systems. The laboratory which has pioneered this
approach is the one headed by the late Prof. Ichiro Kato and now by Prof. Atsuo Takanishi at
Waseda University, which has developed robotic devices capable of playing different musical
instruments such as the organ, piano, violin and flute. They also developed a system for
investigating the function of mastication in humans.Prof. Kato himself (ICNR ‟91) and other
investigators have proposed even more intriguing speculations on the relations between
human mind and robot mind. Based on these hypotheses the Waseda laboratory is currently
investigating an approach to the assistance to the disabled and the elderly which involves not
merely the concept of “service robots,” but even the one of robots as “companions‟.


8. APPLICATIONS

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1) General surgery

Many general surgical procedures can now be performed using the state of the art robotic
surgical system. In 2007, the. University of Illinois at Chicago medical team, lead by Prof.
Pier Cristoforo Giulianotti, performed the world's first ever robotic pancreatectomy and also
the Midwests fully robotic Whipple surgery, which is the most complicated and demanding
procedure of the abdomen. In April 2008, the same team of surgeons performed the world's
first fully minimally invasive liver resection for living donor transplantation, removing 60%
of the patient's liver, yet allowing him to leave the hospital just a couple of days after the
procedure, in very good condition. Furthermore the patient can also leave with less pain than
a usual surgery due to the four puncture holes and not a scar by a surgery.




2) Cardiothoracic surgery


Robot-assisted MIDCAB and Endoscopic coronary artery bypass (TECAB) surgeries are being
performed with the da Vinci system. Mitral valve repairs and replacements have been
performed. East Carolina University, Greenville (Dr W. Randolph Chitwood), Saint Joseph's
Hospital, Atlanta (Dr Douglas A. Murphy), and Good Samaritan Hospital, Cincinnati (Dr J.
Michael Smith) have popularized this procedure and proved its durability with multiple
publications. Since the first robotic cardiac procedure performed in the USA in 1999, The
Ohio State University, Columbus (Dr. Robert E. Michler, Dr. Juan Crestanello, Dr. Paul Vesco)
has performed CABG, mitral valve[[, esophagectomy, lung resection, tumor resections,
among other robotic assisted procedures and serves as a training site for other surgeons. In
2002, surgeons at the Cleveland Clinic in Florida (Dr. Douglas Boyd and Kenneth Stahl)
reported and published their preliminary experience with minimally invasive "hybrid"
procedures. These procedures combined robotic revascularization and coronary stenting
and further expanded the role of robots in coronary bypass to patients with disease in
multiple vessels.


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3) Gastrointestinal surgery


Multiple types of procedures have been performed with either the Zeus or da Vinci robot
systems, including bariatric surgery



4) Urology

The da Vinci robot is commonly used to remove the prostate gland for cancer, repair
obstructed kidneys, repair bladder abnormalities and remove diseased kidneys. New
minimally invasive robotic devices using steerable flexible needles are currently being
developed for use in prostate brachytherapy. A few leading urologists in the field of robotic
urological surgery are Drs. David Samadi, Ashutosh Tewari, Mani Menon, Peter Schlegel,
Douglas Scherr, Darracott Vaughan, and Vipul Patel.




5) Radiosurgery

The CyberKnife Robotic Radiosurgery System uses image-guidance and computer controlled
robotics to treat tumors throughout the body by delivering multiple beams of high-energy
radiation to the tumor from virtually any direction also determined.




9. CONCLUSION

The reasons why robots did not gain immediate acceptance in the medical community are
both obvious, and subtle. The obvious reasons are both psychological (robots may be
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perceived as “competitors” by physicians, and as potentially dangerous exotic machines by
patients), technical (industrial robots are reliable, but no real expertise exists in the worl about
robots working full time in the vicinity or even in contact with humans), and economical
(most service robots are quite expensive). The subtle reasons aye related to a possible
misconception of the very same notion of robots, which should probably be revised in the
robotics research community. In fact, most users perceive robots either as the industrial robot
arm, or as an exotic and anthropomorphic creature. In the field of advanced robotics, and of
medical robotics in particular, the robot leaves the factory floor and gets into physical contact
with the human operator (the surgeon, the patient). In some cases, the robot will maintain the
overall usual structure of an industrial robot (although new robot arms dedicated to medical
applications are being presented), but in most other cases robotics technologies will be
embedded into tools which will not possess the traditional robotic “look.” This shift should
not be seen, in our opinion, as a problem, but rather as a very interesting and attractive
opportunity for the robotics research community to extend our reach to a broader area
(sometimes referred to as “mechatronics in medicine” or even“bio-mechatronics” ) .
Nevertheless, the concrete experimental and clinical results achieved both in the fields of
“macro” and “micro” medical robotics, and only partially reported in this paper,together with
the economical and social motivations for usingthese new technological tools, permeated by
robotics technologies,could certainly represent the best viaticum for a massive development
of this new area of robotics in the near future.




10. REFERENCES




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[1]   Y.S.Kwoh,J.Hou,         E.A.Jonckheere,S.Hayati,S.Hayati:”A     Robot     with
Improved Absolute Positioning Accuracy for CT Guided Stereotactic Brain
Surgery” ,IEEE Transaction on Biomedical Engineering,vol.35,feb.2007




[2] M.Morishita,Y.Hatamura:”Robotics in survey” IEEE Engineering in
medical & biological Magazine special issue on,vol 14 no.3




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