1.wb2432, biomechatronicswb2432Rehabilitation RoboticsDick PlettenburgRichard van der Linde 3mE, BMechE 14:31 slide: 1

2. wb2432, biomechatronics This lecture CONTENT Introduction & definitions Robot control schemesPart 1 Identification & diagnostics robots Therapy robots Assistive robotsPart 2 Prosthetics The future of rehabilitation robots Video: ARMPart 3 14:31 slide: 2 3. wb2432, biomechatronicsIntroduction & definitionsDefinition of the word robotrobota [Czech], play of Karel Capec 1921means work, or forced workers, or slavesDictionary:1. A mechanical device that sometimes resembles a human being and is capable of performing a variety of often complex human tasks on command or by being programmed in advance.2. A machine or device that operates automatically or by remote control.3. A person who works mechanically without original thought, especially one who responds automatically to the commands of others. 14:31 slide: 3 4. wb2432, biomechatronics Introduction & definitionsFiction robots1956, Forbidden1977, Star Wars1999, TerminatorPlanet 14:31 slide: 4 5. wb2432, biomechatronics Introduction & definitions1961, first real robot 1970-1999 over 1.100.000 industrialThe first industrial robot, called robots installedUnimate, GM factory in NewJersey NO human interaction !!! 14:31slide: 5 6. wb2432, biomechatronicsIntroduction & definitionsfirst steprobots service manufacturing robots robotsadaptation speedautonomy accuracysafety payloadreliability14:31slide: 6 7. wb2432, biomechatronics Introduction & definitionsService robots are robots which operate semi of fullyautonomously to perform services useful to the well-being ofhumans and equipment, excluding manufacturing operations(World Robotics 2000, The Int. Fed. of Rob., United Nations)example application areas: cleaning robots (tank, floor, window, pipes, etc.) inspection robots (power plants, nuclear, etc.) domestic robots (vacuum, lawn, etc.) medical robots (surgical assistance, equipment holder) assistive robots (for disabled persons) entertainment14:31slide: 7 8. wb2432, biomechatronicsIntroduction & definitionsRobotics covers an extensive field of research(sessions on ICRA 2000, San Francisco, USA)path planningflexible robotsvisual servoingmapping and localization robot controlfuzzy logic systemsgrasping and manipulationdexterous manipulation humanoidskinematics robot learning navigation and mappingmechanisms novel transmission methods haptic interfacesarchitecturessurgical robotslegged locomotionmicro robots target trackingrapid prototypingmanufacturing system designredundant manipulators vision based controlspace robots and roversmobile roboticsmemsautonomous robotsreconfigurable robotsstiffness an compliancespace and underwater robotsnonholonomic motion planning actuatorsrange sensingneural network systems collision detectionpart feeding and fixingcooperative robots novel sensing techniquesrehabilitation robotsmechatronics dynamics and optimizationassembly and motion planning parallel manipulatorsbiped robotsenvironmental modeling tele-operation flexible assembly systems14:31slide: 8 9. wb2432, biomechatronicsIntroduction & definitionsRobotics covers an extensive field of research(sessions on ICRA 2000, San Francisco, USA)path planningflexible robotsvisual servoingmapping and localization robot controlfuzzy logic systemsgrasping and manipulationdexterous manipulation humanoidskinematics robot learning navigation and mappingmechanisms novel transmission methods haptic interfacesarchitecturessurgical robotslegged locomotionmicro robots target trackingrapid prototypingmanufacturing system designredundant manipulators vision based controlspace robots and roversmobile roboticsmemsautonomous robotsreconfigurable robotsstiffness an compliancespace and underwater robotsnonholonomic motion planning actuatorsrange sensingneural network systems collision detectionpart feeding and fixingcooperative robots novel sensing techniquesrehabilitation robotsmechatronics dynamics and optimizationassembly and motion planning parallel manipulatorsbiped robotsenvironmental modeling tele-operation flexible assembly systemsExtended into 168 sessions at ICRA 2007, Roma, Italy14:31slide: 9 10. wb2432, biomechatronicsIntroduction & definitionsDefinition of the word rehabilitation"The entirety of medical and social means, which have the goal torestore the functions of the patients as far as possible"(Dikke Van Dale)Rehabilitation robots are service robots which operate semi offully autonomously to perform services useful to the well-being ofdisabled humans(R.Q. van der Linde, 2003) 14:31 slide: 10 11. wb2432, biomechatronicsIntroduction & definitions4 functional areas of rehabilitation robots:identification & diagnostics therapy assistance prostheticsliving assistance 14:31 slide: 11 12. wb2432, biomechatronicsWhy rehabilitation robots ? We have an increasing need for treatment more elderly people more diseases Robot therapy might be effective motivating accurate objective adaptive Robot therapy enables home care14:32slide: 12 13. wb2432, biomechatronics Why NOT rehabilitation robots ? Because the QALY factor is lowQALY (Quality Adjusted Life Year)goal: to measure the value quality of lifedefinition:1 year of perfect health-life expectancy is worth 1QALY = quality of lifeexamples: - 4 year life extension * 0.1 = 0.4 QALY (rehab)- 2 year life extension * 1 = 2 QALY (e.g. pace maker)NL: QALY = 25.000 Euro Because proven therapy results are required first ! Because it is complex14:32slide: 13 14. wb2432, biomechatronics Technical issuesInteraction between (disabled) human operator and robotHUMAN ROBOT what type of motion control is required ? how to interface with the robot ? reliability safety14:32slide: 14 15. wb2432, biomechatronics Types of movement controlposition control force/position periodic B controlBA=BAA 1. impedance 1. forced1. position control2. admittance2. ballistic2. force control 3. intrinsic 14:32 slide: 15 16. wb2432, biomechatronicsTypes of movement controlposition control BAWhen ?prescribed displacement, e.g. movement of manipulatorsprescribed force, e.g. pinching14:32slide: 16 17. wb2432, biomechatronics Position controlSimple classical control loopXreffXrealcontrolleractuator loadsensorXmeas14:32slide: 17 18. wb2432, biomechatronics Position controlExample: simplest control loopsuppose 2nd order load cmx = f x cx fact. loadrewritingx1 c =f ms 2 +s +cxor 1 c x=displacement xc = 2 0 =f=force f s s +2 +1 mc=stiffness0 20 =damping 14:32 slide: 18 19. wb2432, biomechatronicsPosition controlExample: simplest control loop, block schemecontroller motor loadXref F1 Xreal Ds + PKms 2 +s +c 1 Xmeas sensorideal sensorsideal motor 14:32 slide: 19 20. wb2432, biomechatronics Position controlExample : simplest control loop, high & low load Step Response From: U(1) 1.4 m=10 settings: m=1 1.2b=0.31c=0Amplitude 0.8To: Y(1) 0.6P=10 0.4D=9 0.20 0 2 4 68 10 12Time (sec.)Conclusion:Safe & optimal control loop settings depend on load !! 14:32 slide: 20 21. wb2432, biomechatronics Position controlCommercial products: hobby servo gearspot. meter miniature motor controller14:32slide: 21 22. wb2432, biomechatronics Position controlExample projects with hobby servos MorphDappie14:32slide: 22 23. wb2432, biomechatronicsForce control from position to force control X2X2Fref. XX1ref X1X Freal. 1position controller ccspring pos. forcecontrolF = cdXX1 X214:32slide: 23 24. wb2432, biomechatronics Force controlseries elastic actuators [Pratt G. 1997]-improve shock tolerance-use cheap motors-use energy storage Movie Flamigo-walking14:32slide: 24 25. wb2432, biomechatronics Position controlDiscussion position control loop Simple & effective technique = cheap !! Easy extension to trajectory control Parallel control loops for multiple DOFs possible Most frequently used type of control More complex control algorithms possible Also usable for speed & force control Optimal gain settings depend on the load 14:32 slide: 25 26. wb2432, biomechatronicsTypes of movement control force/position controlB AWhen ?simultaneous control of force & positione.g. reaching, human interaction 14:32 slide: 26 27. wb2432, biomechatronicsForce/position controlImpedance control loop HUMAN ROBOdisplacement desired end point virtuaforce actuator body senso+dynamics +robot inertia -interaction force14:32slide: 27 28. wb2432, biomechatronics Force/position controlmovement HUMAN ForceROBOTDiscussion impedance control loopno elimination of robot inertiano elimination of mechanical frictionmeasure displacement before giving forceno force sensor requiredconclusion:good for soft & light tasks, high safety ! 14:32 slide: 28 29. wb2432, biomechatronics Force/position controlExample impedance controlled devices14:32slide: 29 30. wb2432, biomechatronics Force/position controlAdmittance control loopposition loop !HUMANROBOT interaction desired end pointforce trajectory actuator bodyforce virtualcontroller + sensor dynamics + -robot inertia sensorend point trajectory14:32slide: 30 31. wb2432, biomechatronicsForce/position control ForceHUMAN movement ROBOTDiscussion admittance control looplimited elimination of robot mass & inertiameasure force change before displacement givenforce sensor requiredinstability for very high gainsconclusion:good for hard & heavy tasks, lower safety 14:32 slide: 31 32. wb2432, biomechatronicsForce/position controlExample admittance controlled devices 14:32 slide: 32 33. wb2432, biomechatronics Force/position controlUsing actuator intrinsic propertiesC2 high C1C2equilibrium point hypothesis, Feldmann14:32slide: 33 34. wb2432, biomechatronicsForce/position controlExampleDUT, DBL 6 muscles, 4 DOF 14:32 slide: 34 35. wb2432, biomechatronicsTypes of movement controlperiodic control A=B When ? repetitive motion (e.g. walking)14:32slide: 35 36. wb2432, biomechatronicsPeriodic controlIntrinsic periodic movementuse mass-spring properties to generate oscillation14:32slide: 36 37. wb2432, biomechatronics PeriodicExamples "passive" walking, DUT Movie Mike-outsidespringy legs, MIT Movie MuseonsideMovie Horseless-rob14:32slide: 37 38. wb2432, biomechatronics PeriodicExample: "passive" walking, Denise, DUT Movie Denise-314:32slide: 38 39. wb2432, biomechatronicsRobot identification & diagnosis 14:32 slide: 39 40. wb2432, biomechatronics Delft UniversityDelft Shoulder Groupneuro-muscular modelingparameter identification by perturbationfrequency domain approachnew diagnosis tools ?Admittance controlled devices 14:32 slide: 40 41. wb2432, biomechatronicsrobot therapy 14:32 slide: 41 42. wb2432, biomechatronicsGentleMovie Gentle14:32slide: 42 43. wb2432, biomechatronics GentleGoalThe aims of GENTLE/S will require established stroke rehabilitation practices tobe altered to accommodate machine mediated therapiesResults8 subjects found therapy motivatingno clinical data available yetAdmittance controlled deviceset up (4 DOF)14:32 on-going researchslide: 43 44. wb2432, biomechatronicsGentlemechanics Haptic Masterforce sensor 14:32 slide: 44 45. wb2432, biomechatronicsMIT MANUSgoal:The goal of the project is to develop, implement and test a robotic system forphysical therapy and neurological rehabilitation.motivation:Some 700,000 US citizens suffer strokes every yearCost of care 30 B$Of these, some 500,000 require therapy for problems with language, memory or movement.The MIT robot focuses on the last of theseset up (3DOF)Impedance controlled device14:32 on-going researchslide: 45 46. wb2432, biomechatronics Rutgers AnkleMotivationThe Rutgers ankle is for patients that need ankle and knee rehabilitation, bothfor orthopedic and stroke diagnosesinterface 6 DOF Steward platform 14:32 slide: 46 47. wb2432, biomechatronicsRutgers Ankleexperiments:3 ankle sprain subjectsresults:improvements in range of motionimprovements in torque generation cap.improvements in ankle work set up14:33 on-going researchslide: 47 48. wb2432, biomechatronicsLokomatHacoma, Zurichcommercial device !gait generation (no impedance, just position!)spinal cord injuriesmainly research applications 14:33 slide: 48 49. wb2432, biomechatronicsLokomatMovie Locomat I 14:33 slide: 49 50. wb2432, biomechatronicsLokomatMovie Locomat II14:33slide: 50 51. wb2432, biomechatronicsLopes University of Twente14:33slide: 51 52. wb2432, biomechatronicsLopes University of TwenteMovies Lopes I & II14:33slide: 52 53. wb2432, biomechatronicsassistive robots14:33slide: 53 54. wb2432, biomechatronics Wheelchair robotsUses: self care cooking shopping scratching ...Autonomy !14:33slide: 54 55. wb2432, biomechatronicsWheelchair robots Movie Beyond 14:33 slide: 55 56. wb2432, biomechatronicsWheelchair robotsDesign criteria stability Joystick input End point control Safety (close to the face) Movement repertoire -eating -page turning -pouring (Voice recognition)Manus ARM, Exact Dynamics price (below 30k Euro) 2 kg load 20 kg weight autonomous 25.000 Euro 14:33 slide: 56 57. wb2432, biomechatronics Living assistance Movie Care-O-botCare-O-bot CarebotFraunhofer IPA Gecko Systems14:33slide: 57 58. wb2432, biomechatronicsLiving assistanceHONDA Humanoid Fully assistive household (future) Remote controlled operationsSpecs Walking & turning (i-walk) Maneuvering (e.g. stairs) Stereo vision 26 DOFs Movie Asimo Intelligence ? 250.000 Euros14:33slide: 58 59. wb2432, biomechatronicsLiving assistance1986 19911993 199619972000E0-E3 E4-E6 P1 P2P3Asimo 175 kg210 kg 130 kg 52 kg 1.9 m 1.8 m1.6 m1.2 m 14:33~500.000.000 Euros development costs slide: 59 60. wb2432, biomechatronics Living assistanceMovie Asimo on Stairs Movie Asimo RunningHonda Asimo 14:33 slide: 60 61. wb2432, biomechatronics Cleaning & domesticSpecialized functions: Vacuum cleaning Lawn mowing Window cleaning Floor cleaning Roomba TrylobiteKey technologies: Obstacle avoidance Environmental map making Path planning (Energy supply) SIRIUSc solar mower 14:33 slide: 61 62. wb2432, biomechatronicsProsthetics 14:33 slide: 62 63. wb2432, biomechatronicsMain issuescommunication with the human bodyweight (stump load, energy consumption)controllabilitycosmesisdurability14:33slide: 63 64. wb2432, biomechatronicsstoring energy in elastic deformationelectronically controlled knee14:33slide: 64 65. wb2432, biomechatronicsFuture on rehabilitation robots14:33slide: 65 66. wb2432, biomechatronics Numbers & trends predicted number of service robots installed(World Robotics 2002, 2006; The Int. Fed. of Rob., United Nations)segment up to 1999 2000-20032005cleaning 400 7005370underwater 900 2005680medical8005.000 3475rehabilitation 200 200 n.a.domestic 3.000310.000*1.9x106**entertainment1x106other1.3004.300 12.000total6.600 319.400 3x106 * = 270.000 vacuum cleaning14:33 ** = 1.8x106 vacuum cleaning slide: 66 67. wb2432, biomechatronicsFuture perspectiveActivities in the field announce an exciting future: Robotic technology is evolving rapidly Robotic systems in the (toy) store Robotic systems in the operating room Robotics systems at home Robotic systems in the media Robotic (sub-) technologies in other fields Robotic systems are entering our life !But rehabilitation robots ......many questions to be answered14:33slide: 67 68. wb2432, biomechatronics Future perspectiveRehabilitation robots is still a small market because: QALY is very low (so cheap technology is required) therapy: no proven efficiency yet, upcoming identification: complex, needs a lot of research prosthetics: too complex, relative small population has benefit assistive: due to large market great futureChange drivers: aging population technology advancement14:33slide: 68 69. wb2432, biomechatronicsWheelchair robots: ARM Movie ARM14:33slide: 69