1242 Part F Field and Service Robotics Functional neural stimulation techniques(FNS)seek exists modular circuitry in the spinal cord,and perhaps to stimulate the residual nervous system electrically elsewhere,that can be electrically activated in order to reanimate the limbs.FNS for standing,walking, to produce coordinated patterns of muscle activity in reaching and grasping has been demonstrated,but these multiple muscles.Thus,one electrode can produce coor- techniques have met with limited commercial success dinated,multijoint muscle activity,reducing the number because of a combination of factors,including ease of of needed control sites,and perhaps improving the use of systems that use surface electrodes,duration of smoothness and time to fatigue of the resulting contrac- use before fatigue,risk from implantation and complex- tions because of use of more natural muscle recruitment ity of the associated control problems.The systems that mechanisms. have been most successful are foot-drop stimulators, which aid individuals who suffer from neurologic con- 53.4.5 Embedded Intelligence ditions in lifting a drooping foot while walking.These systems detect the phase of the gait cycle(using a foot Recent robotics-related advances for prosthetic legs have switch or accelerometer,for example)and then stimulate included embedding microprocessors and passive brak- a nerve in the leg to lift the foot at the appropriate time. ing systems into artificial knees,so that the knees can,for Two recent innovations may help move the FNS field example,be made relatively stiff during the stance phase forward.The first innovation is a hardware innovation. of gait,and free to move during the swing phase of gait The bionic neuron (BION)is an injectable stimulator (see the review in [53.142]).The first microprocessor the size of a very large grain of cooked rice [53.140]. knee introduced was the Otto Bock C-Leg,introduced The initial version is powered through electromagnetic in 1999.The C-Leg uses a servomotor to adjust valves to transduction via a coil on the outside of the body,but hydraulic pistons.The rechargeable battery lasts about versions are under development that include a battery. 24 hours.The pattern of resistance throughout the gait 53.5 Communication with the individually addressable,pro- cycle can be adjusted for each user.A dramatic exam- grammable stimulator on the BION is through radio ple of the benefit of the C-Leg is the story of a man who frequencies.Sensors,including accelerometers,can also made it down from the 70th floor of the World Trade be packaged into the capsule,so that the multiple im- Center on 9th September 2001 with only minor bruising planted devices could communicate with themselves to to his residual stump [53.143].Other microprocessor- calculate limb position.Two potential advantages of the controlled knees are the Endolite adaptive prosthesis, BION which may make FNS more practical are that which uses pneumatic and hydraulic valves,the Rheo it can be inserted without surgery (using a large-gauge Knee(Ossur hf,Iceland),which uses magnetorheologic needle).and that it may be more robust and resistant to fluid to vary the knee impedance,and the Intelligent infections,since it does not require implanted wires that Prosthesis. can become roadways for infections to spread. The first powered knee that can generate power, The second innovation that may push FNS forward rather than just dissipate energy,is currently being com- is stimulating the control circuits in the nervous sys- mercialized by Ossur as the Power Knee.The system tem rather than individual muscles.For example,it combines an electromechanical power source that will has been shown that locomotor-like movements can be be controlled with input from sensors on the sound leg eliciting in multiple muscles of the cat hind limb by shoe.Initial reports suggest that this is the first knee that stimulating regions of the spinal cord directly (see re- allows the user to walk up stairs with a step-over-step view [53.141]).The key realization here is that there pattern. 53.5 Augmentation for Diagnosis and Monitoring 53.5.1 Introduction:Grand Challenges monitoring.tele-health services,and institution-based and Enabling Technologies monitoring automation are all examples of systems be- ing developed to improve the quality of life for both A critical aspect of rehabilitation is health maintenance persons at risk as well as their care-givers.Institutional with age-related or degenerative functional decline and systems of this nature,more properly part of the field of after a medical intervention.In-home diagnostic equip- clinical engineering,are incorporating more robotic,net- ment,devices worn on or in the body for vital signs worked,and autonomous devices to take more accurate1242 Part F Field and Service Robotics Functional neural stimulation techniques (FNS) seek to stimulate the residual nervous system electrically to reanimate the limbs. FNS for standing, walking, reaching and grasping has been demonstrated, but these techniques have met with limited commercial success because of a combination of factors, including ease of use of systems that use surface electrodes, duration of use before fatigue, risk from implantation and complex￾ity of the associated control problems. The systems that have been most successful are foot-drop stimulators, which aid individuals who suffer from neurologic con￾ditions in lifting a drooping foot while walking. These systems detect the phase of the gait cycle (using a foot switch or accelerometer, for example) and then stimulate a nerve in the leg to lift the foot at the appropriate time. Two recent innovations may help move the FNS field forward. The first innovation is a hardware innovation. The bionic neuron (BION) is an injectable stimulator the size of a very large grain of cooked rice [53.140]. The initial version is powered through electromagnetic transduction via a coil on the outside of the body, but versions are under development that include a battery. Communication with the individually addressable, pro￾grammable stimulator on the BION is through radio frequencies. Sensors, including accelerometers, can also be packaged into the capsule, so that the multiple im￾planted devices could communicate with themselves to calculate limb position. Two potential advantages of the BION which may make FNS more practical are that it can be inserted without surgery (using a large-gauge needle), and that it may be more robust and resistant to infections, since it does not require implanted wires that can become roadways for infections to spread. The second innovation that may push FNS forward is stimulating the control circuits in the nervous sys￾tem rather than individual muscles. For example, it has been shown that locomotor-like movements can be eliciting in multiple muscles of the cat hind limb by stimulating regions of the spinal cord directly (see re￾view [53.141]). The key realization here is that there exists modular circuitry in the spinal cord, and perhaps elsewhere, that can be electrically activated in order to produce coordinated patterns of muscle activity in multiple muscles. Thus, one electrode can produce coor￾dinated, multijoint muscle activity, reducing the number of needed control sites, and perhaps improving the smoothness and time to fatigue of the resulting contrac￾tions because of use of more natural muscle recruitment mechanisms. 53.4.5 Embedded Intelligence Recent robotics-related advances for prosthetic legs have included embedding microprocessors and passive brak￾ing systems into artificial knees, so that the knees can, for example, be made relatively stiff during the stance phase of gait, and free to move during the swing phase of gait (see the review in [53.142]). The first microprocessor knee introduced was the Otto Bock C-Leg, introduced in 1999. The C-Leg uses a servomotor to adjust valves to hydraulic pistons. The rechargeable battery lasts about 24 hours. The pattern of resistance throughout the gait cycle can be adjusted for each user. A dramatic exam￾ple of the benefit of the C-Leg is the story of a man who made it down from the 70th floor of the World Trade Center on 9th September 2001 with only minor bruising to his residual stump [53.143]. Other microprocessor￾controlled knees are the Endolite adaptive prosthesis, which uses pneumatic and hydraulic valves, the Rheo Knee (Ossur hf, Iceland), which uses magnetorheologic fluid to vary the knee impedance, and the Intelligent Prosthesis. The first powered knee that can generate power, rather than just dissipate energy, is currently being com￾mercialized by Ossur as the Power Knee. The system combines an electromechanical power source that will be controlled with input from sensors on the sound leg shoe. Initial reports suggest that this is the first knee that allows the user to walk up stairs with a step-over-step pattern. 53.5 Augmentation for Diagnosis and Monitoring 53.5.1 Introduction: Grand Challenges and Enabling Technologies A critical aspect of rehabilitation is health maintenance with age-related or degenerative functional decline and after a medical intervention. In-home diagnostic equip￾ment, devices worn on or in the body for vital signs monitoring, tele-health services, and institution-based monitoring automation are all examples of systems be￾ing developed to improve the quality of life for both persons at risk as well as their care-givers. Institutional systems of this nature, more properly part of the field of clinical engineering, are incorporating more robotic, net￾worked, and autonomous devices to take more accurate Part F 53.5