LI, Chunguang, INOUE, Yoshio, LIU Author(s), Kyoko, OKA, Koichi.

Transcription

1 Kochi Univerity of Technology Aca Ipleentation of a Co Title ave Robotic Syte with Force Fee y Recycling LI, Chunguang, INOUE, Yohio, LIU Author(), Kyoko, OKA, Koichi Dyna Citation 25 Date of 2010 iue URL (c) 2010 The Japan Society of Mec Right r Text verion publiher Kochi, JAPAN

2 Ipleentation of a Copact Mater-Slave Robotic Syte with Force Feedback and Energy Recycling* Chunguang LI **, Yohio INOUE **, Tao LIU **, Kyoko SHIBATA ** and Koichi OKA ** ** Kochi Univerity of Technology 185 Miyanokuchi, Toayaada-Cho, Kai-City, Kochi, Japan E-ail: u@g.kochi-tech.ac.jp Abtract Mater-lave control i becoing increaingly popular in the developent of robotic yte which can provide rehabilitation training for heiplegic patient with a unilaterally diabled lib. However, the yte tructure and control trategie of exitent ater-lave yte are alway coplex. An innovative ater-lave yte ipleenting force feedback and otion tracking for a rehabilitation robot i preented in thi paper. The yte conit of two identical otor with a wired connection, and the two otor are located at the ater and lave anipulator ite repectively. The lave otor track the otion of the ater otor directly driven by a patient. A well, the interaction force produced at the lave ite i fed back to the patient. Therefore, the ipaired lib driven by the lave otor can iitate the otion of the healthy lib controlling the ater otor, and the patient can regulate the control force of the healthy lib properly according to the force enation. The force ening and otion tracking are achieved iultaneouly with neither force enor nor ophiticated control algorith. The yte i characterized by iple tructure, bidirectional controllability, energy recycling, and force feedback without a force enor. Tet experient on a prototype were conducted, and the reult appraie the advantage of the yte and deontrate the feaibility of the propoed control chee for a rehabilitation robot. Key word: Force Feedback, Mater-Slave Motion Tracking, Bidirectional Control, Energy Recycling 1. Introduction *Received 15 Sep., 2009 (No ) [DOI: /jdd.4.13] Copyright 2010 by JSME Mater-lave control chee have attracted ignificant attention recently due to their wide potential application in hoe-baed rehabilitation robotic yte which ay upport hoe treatent of heiplegic patient (1)-(3), teleoperation yte that enable huan to interact with reote or hazardou environent (4), and icroanipulation yte that allow huan to control object in inacceible icroenvironent, in field uch a cell anipulation, icroaebly, and icrourgery (5)-(8). It i widely accepted that otion tracking ability in lave anipulator i eential in thoe yte. In addition, force feedback i alo deirable ince a kinethetic feel of interaction force can guide huan operator to deterine an appropriate input force according to variou handling environent. Traditionally, force feedback i realized by ean of variou force/torque enor (9)-(11), which increae control coplexity a well a yte cot. Beide, it i extreely difficult 13

3 to ount enor in icroenvironent. W-EXOS (12) wa an exokeleton robot developed for aiting forear and writ otion of phyically weak patient. Baed on the individual otion intention, the robot can deliver aitance for uer to perfor otion of forear pronation/upination,writ flexion/extenion and ulnar/radial deviation oothly and naturally. However, a three axi force enor and two torque enor were required to obtain the force and torque inforation. Ueki et al (13) introduced a hand otion ait robot for independent rehabilitation therapie. With the yte, the ipaired hand of a patient wa driven by hi/her healthy hand on the contralateral ide. The yte wa characterized by virtual reality environent diplaying. The clinical tet on ix patient verify that the patient otivation for the rehabilitation wa iproved and enhanced. However, the force inforation wa acquired by eploying force enor. A huan-like robot hand (14) wa developed with high-power and low-preure pneuatic actuator. And a ater-lave yte wa contructed to enable the robot hand to achieve oveent in the ae anner a the operator. The applied pneuatic actuator can drive the robot hand to grap object with enough force. However, in order to control the contact force between the robot hand and the object, a preure enor and a force enor were adopted and force control wa required. On the other hand, the traditional interaction between the ater and lave anipulator i alway realized through the internet, which tranit control coand to the lave anipulator and the interface force in the lave ite to the operator. However, few yte achieved direct electric power traniion between the ater and the lave device. That i, in order to drive the lave anipulator, a pecialized power odule i needed. In addition, traditional ater-lave yte generally upport unilateral control and the location of the ater and lave device are fixed. When the yte i developed to ipleent rehabilitation treatent for heiplegic patient with a unilaterally diabled lib, thi i unfavorable becaue it i uncertain that which lib i ipaired. In thi paper, we propoe a new ater-lave control yte to realize force feedback without a force enor and to achieve otion tracking with a kind of energy recycling. Moreover, the yte can realize bidirectional control with a copact tructure. A an application tudy, a prototype baed on the control yte i developed to ipleent rehabilitation training for heiplegic patient with a unilaterally ipaired lib. Noenclature J : inertial oent C T : otor torque contant R : arature reitance uation of the two otor L : arature inductance uation of the two otor T 0 : unload torque T M : otor electroagnetic torque T : external acting torque in one terinal e : arature voltage i : current in the cloed-loop circuit a : rotor angular acceleration ω : angular velocity in one terinal θ : angular poition in one terinal N : gear ratio 14

4 η : working efficiency of the otor α : duty cycle of the PWM ignal K P, K I, K D : proportional, integral and differential coefficient λ T : force feedback coefficient P M, P up, P R : otor electroagnetic power, uppleentary energy power and reitance lo power Subcript : ater : lave 2. Method 2.1 Mater-lave yte The ater-lave control yte i copoed of two identical otor, with the ater otor being operated by a huan operator and the lave otor following the ater to ipleent the tak coanded by the operator. The two otor have a directly wired connection and thu contitute a cloed-loop circuit. The ater otor a a generator power the lave otor, which connect with a otion output terinal. An equivalent circuit diagra i hown in Fig. 1, in which M and M repreent the ater and the lave otor. Even though the hardware configuration at the two ite i yetric, in order to expre the light difference in pecification, the variable in the ater and the lave ite are denoted with the ubcript and repectively. Fig. 1. Equivalent circuit diagra of the ater-lave yte 2.2 Theoretical forulation Baed on the dynaic echani, the otion equation i written a where T and Tη = ( TM _ + T0 _ + J a ) N T = ( TM _ T0 _ J a ) N η TM _ = CT _ i, TM _ = CT _ i T tand for the torque exerted in the two terinal; The unload torque (1) T _ 0 and T 0 _ are ainly caued by echanical friction in the otor. The electroagnetic torque of the two otor are approxiately identical ince the current i hared and the torque contant i uch the ae; Inertial torque J a and J a are negligible copared with other torque, thu, they are not conidered in the following analyi. According to Eq. (1), the relationhip between the terinal torque can be expreed a: 15

5 CT _ N 1 N C T = T + ( T0 _ + C N η η η C T _ T _ T _ T 0 _ ) (2) in which the coefficient C N C N T _ T _ and T T _ C _ C approxiate to 1 becaue the yetric tructure. Copared with the influence caued by the working efficiency of the gearboxe, the light difference of the otor in pecification i negligible. Therefore, the relationhip between the terinal torque can be rewritten a: 1 N T = T + ( T0 _ + T0 _ ) (3) ηη η Thi indicate that the torque induced at the two ite correpond to each other. When the interaction force at the lave ite increae, the current a well a the electroagnetic torque of the two otor increae, then, operator can ene thi variation at the ater ite, and increae the input force accordingly to balance the torque between the two terinal. That i, baed on the cloed-loop current, the yte i capable of ipleenting force feedback without uing a force enor. Now, baed on the electrical echani, the dynaic voltage balance equation of the ater-lave circuit can be written a: di Ri + L = e e = CT _ N ω CT _ N ω (4) dt The energy generated by the ater otor i tranitted to the lave otor except the energy loe in the reitance and inductance. The coefficient C T _ N and C T _ N alot have no difference, thu, the ater otor drive the lave otor to ove with a relatively lower velocity. Thi ean that the yte ha a feature of otion iitation with the energy generated by the ater being recycled. Accurate otion tracking can be realized if the energy loe in the circuit are fully copenated. 2.3 Motion tracking controller High otion tracking perforance i neceary for perforing rehabilitation training. However, the energy loe in the circuit ake it ipoible to acquire accurate otion tracking. In order to offet the energy loe in the circuit, a certain aount of energy i copenated for the circuit uing an H-bridge driver. The hardware connection diagra i given in Fig. 2. The control input of the H-bridge driver are a pule-width-odulated (PWM) ignal and a direction control ignal, which control the agnitude and direction of the uppleentary voltage repectively. Baed on the velocity difference and the poition difference between the two terinal, the two control ignal are regulated with PID (proportional-integral-differential) control ethod. The otion control equation i given a: α = K ω P + K (( ω θ P (( θ ω ) + K θ ) + K ω I θ I ( ω ( θ ω ) K θ ) K ω D θ D dω ) dt dθ ) dt The paraeter with the upercript ω and θ ean the coefficient related to the velocity and poition repectively. Becaue a udden change ay happen to the velocity and poition ( ω and θ ) that controlled by operator, the differential operation i applied only to the following velocity and poition ( ω and θ ) rather than the velocity and (5) 16

6 poition difference o a to avoid the overhoot or fluctuation of the yte. The ign and the agnitude of the control variable, α, are ued to witch the direction control ignal and adjut the duty cycle of the PWM ignal repectively. Fig. 2. Connection of the H-bridge driver and the two otor 3. Experient Prototype A hown in Fig. 3, a preliinary tet platfor wa built to verify the propoed control chee. The platfor i ainly copoed of two identical otor/gear unit (A-ax 32 otor, cobined with Planetary Gearhead GP 32 A, N=4.8 and Encoder HEDL 5540, axon, Switzerland), an H-bridge driver (LMD18200, National Seiconductor, U.S.A.), and a dspace control platfor (CLP1104, dspace, Gerany). In addition, two torque tranducer (TP-20KCE, Kyowa, Japan) and a torque ignal aplifier were applied to eaure the input and output torque for verifing force feedback capability. However, they are not required in real application. Slave Mater Aplifier dspace H-bridge driver Torque tranducer Fig. 3. Experiental platfor of the ater-lave yte Here, three tet experient were perfored. One i force feedback tet, which i ued to tetify the capability of force feedback and acceptable feedback perforance; the econd i energy recycling tet, which i ued to appraie the energy recycling capability of the yte; the lat i bidirectional control tet, which i ued to confir the characteritic of bidirectional controllability and the ae working perforance in the two control direction. 17

7 In the firt and econd experient, in order to iplify yte perforance analyi, a DC driving otor wa ued to drive the ater/gear unit intead of a huan operator. It wa coaxially connected to the ater/gear unit and wa driven by another H-bridge driver, here referred to a driver 2, while the driver connected with the ater-lave circuit wa referred to a driver 1. The input voltage of the driving otor wa adjuted baed on the difference between a predefined reference velocity and the velocity in the ater terinal. The cheatic diagra i hown in Fig. 4. In the third experient, an operator exerted force on the both ide with the two hand without uing the DC driving otor and the H-bridge driver 2. The correponding diagra i hown in Fig. 5. In the figure, the ater/lave unit and the otor 1/2 unit ean the cobination of the otor, gearbox, encoder, and the torque tranducer. The torque inforation given with dahed line indicate that it i not required in real appllication. The CLP1104 collected the velocity and poition inforation though the increental encoder interface, worked out the control iganl for the H-bridge driver 1 with the otion tracking controller, enabled the driver to upply a proper aount of energy for the cloed-loop circuit. The energy generated by the ater otor, together with the uppleentary energy, drove the lave otor to track the otion of the ater otor. In addition, the torque inforation wa collected through AD odule of the CLP1104 for verifying the force feedback capability and bidirectional controllability. For the firt and the econd experient, the CLP1104 alo calculated the control ignal for the H-bridge driver 2 and regulated the input voltage of the DC driving otor, which further rotated the yte with the reference velocity. Meanwhile, the cloed-loop current obtained with the H-bridge driver 1 wa apled through the AD odule of the CLP1104, and the control output of the otion tracking controller (α ) wa recorded for tetifying the characteritic of energy recycling. Fig. 4. Scheatic diagra of the experient with DC driving otor Fig. 5. Scheatic diagra of the experient perfored with the two hand 18

8 4. Experiental Study 4.1 Force feedback tet We attached an increaed reitant force to the lave ite with one hand, and verified the force feedback capability baed on the concoitant regulation of the force at the ater ite. The reitant force wa intentionally exerted with a certain fluctuation o a to tetify the force feedback perforance. The reference velocity wa et a 250 degree/econd. The teted reult are given in Fig. 6, in which the oppoite ign ybol denote the oppoite direction of the two torque. The torque difference ( T dif ) wa the uation of the torque in the two terinal. It actually repreent the difference between the two torque. In thi experient, the otion tracking wa acquired with the axiu tracking error of 2.91 degree/econd in velocity and 0.52 degree in poition. (a) Torque variation curve (b) Force feedback coefficient Fig. 6. Reult correponding to the force feedback tet A hown in Fig. 6 (a), the control torque produced at the ater ite (controlled by the DC driving otor) increaed following the increent of the reitant torque, the force feedback capability of the yte i therefore deontrated. Beide, the control torque wa regulated accordingly even though the variation of the reitant torque wa all, thu, good force feedback perforance i confired. However, the control torque at the ater ite wa larger than the reitant torque, thi wa caued by the unload torque of the otor and the frictional torque induced by the gearboxe (working efficiency). Although there wa a difference in the torque, the force feedback capability can aure the operator to regulate the control force in the ater ite accurately according to the reitance variation in the lave ite. In addition, the torque difference kept nearly contant even though the force 19

9 exerted in the two terinal were increaed. Thi indicate that the varying external acting force had unnoticeable ipact on the unload torque and gearboxe frictional torque o long a the rotational velocitie were kept contant. It i true that the torque difference (ainly caued by the working efficiency of the gearboxe) will change lightly following the variation of the velocity, wherea the operator can ene thi variation and regulate the control force according to the expected rotational velocity. In the conidering application, the variation of the torque difference i very all copared to the variation of the external reitance. Furtherore, the yte i ainly aied at achieving otion tracking and the force tranparency i le eential. Therefore, the torque difference i acceptable for the conidering yte. In order to quantify the force feedback capability of the yte toward the external ipedance variation at the lave ite, we defined force feedback coefficient a: 0 0 k k 0 0 T T T λ T = = (6) T T T where T and T repreent the initial torque when there wa no external reitant force 0 and the yte wa rotated with the velocity of 250 degree/econd. T (0.032 N) wa 0 ued to drive the wor gear at the lave ite. T (0.048 N) wa ued to overcoe the frictional torque in the gearboxe and the unload torque in two otor, further to drive the two otor to rotate; the variable with the upercript k denote the apling value in the k tie. The initial torque were excluded in the calculation for eliinating the effect of unload torque. The force feedback coefficient curve i hown in Fig. 6 (b), the yte realized force feedback with an approxiately contant reflecting coefficient. The average coefficient wa It wa larger than the unit one, the cuae of thi i conidered to be the frictional torque induced by the gearboxe. In order to reduce the requirent for the control force and enhance force preence perforance, the otor and gearbox with higher working efficiencie hould be eployed. 4.2 Energy recycling tet Even though the energy generated by the ater i recycled by the lave otor, a expreed in Eq. (4), the energy lo in the circuit ake the velocity of the lave otor i lower than that of the ater otor. Therefore, we copenated a certain aount of energy to offet the energy lo in the circuit. In order to verify the energy recycling capability, the reference velocity wa et a a ine ignal with an increaing agnitude in different period. That i, the yte wa rotated with clockwie and counter-clockwie direction periodically. No external load wa attached to the lave ite. The electroagnetic power, uppleentary energy power, and the power of the reitance lo were calculated with: P P P M up R = C T _ = αu i 2 = i R in ω = ie where U denote the upply voltage of the H-bridge driver. U wa 12 volt and R wa 6.04 oh. Since ω = ω when the yte achieved otion tracking and the yte wa configured with a yetrical tructure (the correponding coefficient in the two ite are alot identical), P M repreented the electroagnetic power of the two otor actually. The inductance lo wa not conidered becaue that it wa very all and negligible copared to the reitance lo. The electroagnetic power and the uppleentary energy power were ued to verify the energy recycling capability; the uppleentary energy power and the reitance lo were ued to confir the function of the uppleentary energy. (7) 20

10 (a) Velocity tracking curve (b) Relationhip between the otor electroagnetic power, uppleentary energy and the reitance lo Fig. 7. Reult correponding to the energy recycling tet The reult correponding to the energy recycling tet are given in Fig. 7, in which P δ denote the power difference between the copenated energy and reitance lo. Seeing Fig. 7 (a), it can be concluded that accurate otion tracking wa realized in both rotational direction. In thi tet, the axiu velocity and poition error were 4.06 degree/econd and 0.5 degree repectively. A can be een fro Fig. 7 (a) and (b), the electroagnetic power of the lave otor (repreent the electroagnetic power of the two otor) increaed with the variation of the velocity (The power were alway poitive even though the velocity wa negative), wherea the copenated energy had unnoticeable change aong different period. Thi indicate that the driving power of the lave otor cae fro the electric energy generated by the ater otor other than the copenated energy. Hence, the energy recycling capability i confired. Meanwhile, the copenated energy and the reitance lo had the ae varying regulation in each period, thi deontrate that the copenated energy wa ued to offet the energy loe in the circuit. However, the forer wa larger than the latter becaue there were alo inductance lo, a well a the contact lo and excitation lo that are caued by the arature current and alternative agnetic field. The reitance lo accounted a ain part of the energy loe and thu, P R wa relatively large copared to P δ, which reflected the power of the other energy loe in the circuit. However, the copenated energy wa larger than the electroagnetic power of the lave otor becaue of the large energy loe in the circuit. In order to reduce the energy 21

11 loe in the circuit and enhance energy recycling efficiency, the otor with a aller arature reitance hould be conidered in the future application. 4.3 Bidirectional control tet The force feedback echani and the yetric configuration ake the yte have the characteritic of bidirectional controllability. In order to verify thi feature, the DC driving otor that controlled the ater/gear unit and the H-bridge driver 2 were reoved fro the experiental platfor. An operator controlled the acting force on the both ide with the two hand. The exerted force had oppoite direction and different agnitude with the aller one defined a the reitance force and the larger one defined a the control force, and the two otor in the correponding ide behave a the lave and the ater repectively. During the experient, the operator changed the agnitude of the reitant force periodically and regulated the control force according to the feedback force, trying to achieve a oveent with all variation aong different period. The reult coreponding to the two control direction are hown in Fig. 8 and Fig. 9 repectively. Fig. 8 give the reult of the tet when the right hand provided a control force while the left hand ipoed a reiitant force with relatively all agnitude. That i, the otor located at the right hand ite acted a the ater while the other otor acted a the lave; Fig. 9 give the reult of the tet when the left hand provided a control force while the right hand ipoed a reiitant force with relatively all agnitude, and the working tate of the two otor were revered copared to the forer cae. In the both figure, the black line repreent the torque produced on the right hand ide and the the red line repreent the torque produced on the left hand ide, the blue line repreent the difference between the control torque and the reitant torque in the two terinal. It can be een that the accurate otion tracking wa achieved in the both control direction. The axiu veloity and poition error were degree/econd and 0.77 degree when the control direction wa fro right to left, and were degree/econd and 0.41 degree when the control direction wa fro left to right. In addition, the control torque increaed following the increent of the reitant torque in the two control direction. Thi confir that force feedback/ening wa realized in the both control direction and the operator wa able to regulate the control force accordingly baed on the enation of the feedback force. Beide, by coparing Fig. 8 (c) and Fig. 9 (c), it can be concluded that when the reitant torque had the ae agnitude (0.078 N), the control torque (0.115 N) a well a the torque difference (0.037 N) were approxiately indentical for the two control direction. The relut verify that the yte ipleented bidirectional control and achieved alot the ae force feedback perforance for the both control direction. A well, the relationhip between the control torque and the reitant torque are given in Fig. 8 (d) and Fig. 9 (d). We can ee that there were hyteretic error when the reciprocating otion wa carried out for the both control direction. When the reitant torque wa all, the unload torque of the otor and the frictional torque caued by the gearboxe were too large copared to the reitant torque, thu the hyteretic error were obviou. In the teting range of the reitant force, the average hyteretic deviation are N and N repectively; and the tandard deviation are and repectively for the two control direction. When we apply thi ater-lave yte to a rehabilitation robot for training heiplegic patient, the bidirectional controllability allow the yte to provide treatent for patient no atter which lib i diabled or ha weak otor function. Therefore, the propoed ater-lave yte i preferrable for a rehabilitation robot to provide treatent for heiplegic patient with a unilaterally diabled lib. 22

12 Fig. 8. Reult of the tet when the right hand control the oveent of the left hand Fig.9. Reult of the tet when the left hand control the oveent of the right hand 5. Concluion A new ater-lave robotic yte i propoed to achieve otion iitation. The yte realize bidirectional control and ha the capability of force feedback and energy recycling. A prototype wa et up and verification experient were perfored. The experiental reult deontrate the feaibility of the propoed control yte for developing a rehabilitation robot. 23

13 In our new yte, the otion tracking capability ake it poible for heiplegic patient to perfor unaited rehabilitation training in the hoe environent with the unhealthy lib iitating the otion of the healthy lib. Force feedback can give patient a direct enation of the reitant force produced by the ipaired lib, thu enabling the healthy lib to provide a proper control force and avoid unpredictable reaction. The force feedback i realized without a force enor; hence, the yte tructure and the control ethod are iplified greatly. Energy recycling ake a lightweight battery can upply enough power for the yte, further to reduce the weight of the robot. Thi i epecially favorable for patient wearing a portable robot o a to ove around freely. Bidirectional controllability ake the yte have no liitation in hardware configuration, which enable the robotic yte to deliver treatent for heiplegic patient no atter which lib i ipaired. In concluion, the propoed yte i favorable to realize elf-controlled rehabilitation robot for training heiplegic patient in otor function recovery and trength enhanceent. However, there are till oe liitation for the new yte. The force feedback perforance will be degraded when the velocitie have a large variation. Thi i epecially the cae when the otor have large unload torque and the gearboxe have large gear ratio. Thu, the yte i only uitable for the application without obviouly varying velocity. In future tudy, otor and gearboxe with higher working efficiencie will be conidered to reduce the above negative effect. A for the preliinary experiental prototype, the proportional, integral and differential coefficient of the otion tracking controller were jut coarely regulated. The otion tracking preciion will be enhanced by further regulating the coefficient. In addition, otor/gear cobination with larger driving torque/power ay be elected to ake the yte ore uitable for a rehabilitation robot. Reference (1) Peng, Q., Park, H.-S., Zhang, L.-Q., 2005, A Low-Cot Portable Tele-Rehabilitation Syte for the Treatent and Aeent of the Elbow Defority of Stroke Patient, Proc IEEE 9th Int. Conf. on Rehabilitation Robotic, Chicago, Illinoi, 28 June-1 July, pp (2) Li, H., Song, A., 2008, Force aitant ater-lave telerehabilitation robotic yte, J. Southeat Univerity, 24(1), pp (3) Schiele, A., Letier, P., Van Der Linde, R., Van Der Hel, F., 2006, Bowden cable actuator for force-feedback exokeleton, in IEEE Int. Conf. Intelligent Robot and Syte, Beijing, China, pp (4) Alfi, A., Farrokhi, M., 2008, Force reflecting bilateral control of ater-lave yte in teleoperation, J. Intelligent and Robotic Syte: Theory and Application, 52(2), pp (5) Ephanov, A.V., Huruzlu, Y., 1997, Ipleentation of enory feedback and trajectory tracking in active teleanipulation yte, J. Dyn. Syt., Mea., Control, 119(3), pp (6) Vlacho, K., Vartholoeo, P., Papadopoulo, E., 2007, A haptic tele-anipulation environent for a vibration-driven icroechatronic device, in IEEE/ASME Int. Conf. on Advanced intelligent echatronic, pp (7) Ando, N., Korondi, P., Hahioto, H., Developent of icroanipulator and haptic interface for networked icroanipulation, IEEE Tran. Mechatron., IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, 6(4), pp (8) Goran, J.J., Dagalaki, N.G., 2006, Probe-baed icro-cale anipulation and aebly uing force feedback, preented at the 1t Joint Eergency Preparedne and Repone/Robotic and Reote Syte Topical Meeting, pp

14 (9) Mituihi, M., Sugita, N., Pitakwatchara, P., 2007, Force-feedback augentation ode in the laparocopic inially invaive teleurgical yte, IEEE/ASME Tran. Mechatronic, 12(4), pp (10) Lee, Sukhan, Lee, Hahk Sung, 1993, Modeling, deign, and evaluation of advanced teleoperator control yte with hort tie delay, IEEE Tran. Robot. Auto., 9 (5), pp (11) Hara, M., Huang, J., Jung, Y.-M., Yabuta, T., 2006, Baic Study on Senory Apect of a Mater/Slave Syte for Force Telecounication, in Int. Conf. on Intell. Robot Syt. Beijing, China, 9-15 Oct., pp (12) Ranathunga Arachchilage Ruwan Chandra GOPURA, Kazuo KIGUCHI, 2008, An Exokeleton Robot for Huan Forear and Writ Motion Ait, Journal of Advanced Mechanical Deign, Syte, and Manufacturing, 2(6), pp (13) Ueki, S., Nihioto, Y., Abe, M., Kawaaki, H., Ito, S., Ihigure, Y., Mizuoto, J., Ojika, T., 2008, Developent of virtual reality exercie of hand otion ait robot for rehabilitation therapy by patient elf-otion control, in IEEE Int. Conf. on Eng. Med. Biol. Soc., pp (14) Nobutaka TSUJIUCHI, Takayuki KOIZUMI, Shinya NISHINO, Hiroyuki KOMATSUBARA, Tatuwo KUDAWARA, Maanori HIRANO, 2008, Developent of Pneuatic Robot Hand and Contruction of Mater-Slave Syte,, 2(6), pp