A prototype of a powered knee orthotic device was developed to determine whether fractional external torque and power support to the knee relieves the biomechanical loads and reduces the muscular demand for a subject performing sit-to-stand movements. With this demonstrator, consisting of the subsystems actuation, kinematics, sensors, and control, all relevant sensor data can be acquired and full control is maintained over actuator parameters. A series-elastic actuator based on a direct current motor provides up to 30 Nm torque to the knee via a hinge joint with an additional sliding degree of freedom. For reasons of feasibility under everyday conditions, user intention is monitored by employing a noninvasive, nonsticking muscle activity sensor to replace electromyographic sensors, which require skin preparation. Furthermore, foot plates with force sensors have been developed and included to derive ground reaction forces. The actual knee torque needed to provide the desired support is based on an inverse dynamics model using ground reaction forces signals and leg kinematics. A control algorithm including disturbance feed forward has been implemented. A demonstration experiment with two subjects showed that 23 % of moment support in fact leads to a similar reduction in activation of the main knee extensor muscle.
LordSRClarkRDWebsterIW.Postural stability and associated physiological factors in a population of aged persons. J Gerontol1991; 46(3): M69–M76.
2.
ManiniTMClarkBC.Dynapenia and aging: an update. J Gerontol A Biol Sci Med Sci2012; 67(1): 28–40.
3.
SavelbergHHMeijerK.The effect of age and joint angle on the proportionality of extensor and flexor strength at the knee joint. J Gerontol A Biol Sci Med Sci2004; 59(11): 1120–1128.
4.
DeVitaPHortobagyiT.Age causes a redistribution of joint torques and powers during gait. J Appl Physiol2000; 88(5): 1804–1811.
5.
SamuelDRowePJ.Effect of ageing on isometric strength through joint range at knee and hip joints in three age groups of older adults. Gerontology2009; 55(6): 621–629.
6.
SankaiY.HAL: hybrid assistive limb based on cybernics. In: KanekoMNakamuraY (eds) Robotics research. Berlin, Heidelberg: Springer, 2011, pp.25–34.
7.
SankaiY. Leading edge of cybernics: robot suit HAL. In: Proceedings of the SICE-ICASE 2006 international joint conference, Busan, Korea, 18–21 October 2006. New York: IEEE.
8.
HikiYSugawaraZAshiharaJ.Walking assist device patent. Patent 8740822, USA, 2014.
9.
DollarAMHerrH.Lower extremity exoskeletons and active orthoses: challenges and state-of-the-art. IEEE T Robot2008; 24(1): 144–158.
10.
HerrH.Exoskeletons and orthoses: classification, design challenges and future directions. J Neuroeng Rehabil2009; 6: 21.
11.
CasoloFCinquemaniSCocettaM. On active lower limb exoskeletons actuators. In: Proceedings of the 2008 5th international symposium on mechatronics and its applications, Amman, Jordan, 27–29 May 2008. New York: IEEE.
12.
YanTCempiniMOddoCM. Review of assistive strategies in powered lower-limb orthoses and exoskeletons. Robot Auton Syst2015; 64: 120–136.
13.
ChenFYuYGeY. WPAL for enhancing human strength and endurance during walking. In: Proceedings of the international conference on information acquisition, Jeju City, Korea, 8–11 July 2007. New York: IEEE.
14.
YehT-JWuM-JLuT-J. Control of McKibben pneumatic muscles for a power-assist, lower-limb orthosis. Mechatronics2010; 20(6): 686–697.
15.
HyonSMorimotoJMatsubaraT. XoR: hybrid drive exoskeleton robot that can balance. In: Proceedings of the 2011 IEEE/RSJ international conference on intelligent robots and systems (IROS), San Francisco, CA, 25–30 September 2011. New York: IEEE.
16.
MorimotoJNodaTHyonS. Extraction of latent kinematic relationships between human users and assistive robots. In: Proceedings of the 2012 IEEE international conference on robotics and automation (ICRA), St. Paul, MN, 14–18 May 2012. New York: IEEE.
17.
SongK-TLiaoY-CJianY-L. Sensorless assistive torque design for a lower extremity exoskeleton. In: Proceedings of the 2014 14th international conference on control, automation and systems (ICCAS), Seoul, Korea, 22–25 October 2014. New York: IEEE.
18.
ChenJLiaoW-H. Experimental evaluation of an assistive knee brace with magnetorheological actuator. In: Proceedings of the 2010 IEEE international conference on robotics and biomimetics (ROBIO), Tianjin, China, 14–18 December 2010. New York: IEEE.
19.
WalshCJPaschKHerrH. An autonomous, underactuated exoskeleton for load-carrying augmentation. In: Proceedings of the 2006 IEEE/RSJ international conference on intelligent robots and systems, Beijing, China, 9–15 October 2006. New York: IEEE.
20.
SvenssonWSalomonssonTHolmbergU.Foot orthosis strain sensing in hill walking. In: Proceedings of the 2007 ICORR 2007 IEEE 10th international conference on rehabilitation robotics, Noordwijk, 13–15 June 2007. New York: IEEE.
21.
NakamuraTSaitoKWangZ. Human cooperative motion adapted wearable anti-gravity muscle support system. In: Proceedings of the 2006 IEEE/RSJ international conference on intelligent robots and systems, Beijing, China, 9–15 October 2006. New York: IEEE.
22.
HorstRW. A bio-robotic leg orthosis for rehabilitation and mobility enhancement. In: Proceedings of the annual international conference of the IEEE engineering in medicine and biology society, Minneapolis, MN, 3–6 September 2009. New York: IEEE.
23.
AsbeckATDyerRJLarussonAF. Biologically-inspired soft exosuit. In: Proceedings of the 2013 IEEE international conference on rehabilitation robotics (ICORR), Seattle, WA, 24–26 June 2013. New York: IEEE.
24.
LaiW-YMaHLiaoW-H. HIP-KNEE control for gait assistance with Powered Knee Orthosis. In: Proceedings of the 2013 IEEE international conference on robotics and biomimetics (ROBIO), Shenzhen, China, 12–14 December 2013. New York: IEEE.
25.
KaminagaHAmariTNiwaY. Development of knee power assist using backdrivable electro-hydrostatic actuator. In: Proceedings of the 2010 IEEE/RSJ international conference on intelligent robots and systems (IROS), Taipei, Taiwan, 18–22 October 2010. New York: IEEE.
26.
ChenFYuYGeY. WPAL for human power assist during walking using dynamic equation. In: Proceedings of the 2009 ICMA 2009 international conference on mechatronics and automation, Changchun, China, 9–12 August 2009. New York: IEEE.
27.
DonatiMDe RossiSVitielloN. A distributed pressure sensor to measure human-machine interaction in lower-limb exoskeletons. In: Congresso del Gruppo Nazionale di Bioingegneria, Rome, 26–29 June 2012, http://www.cyberlegs.eu/pdf/conference/Donati2012.pdf
28.
YangZZhuYYangX. Impedance control of exoskeleton suit based on adaptive RBF neural network. In: Proceedings of the 2009 IHMSC’09 international conference on intelligent human-machine systems and cybernetics, Hangzhou, China, 26–27 August 2009. New York: IEEE.
29.
KongKBaeJTomizukaM.A compact rotary series elastic actuator for human assistive systems. IEEE/ASME T Mech2012; 17(2): 288–297.
30.
SasakiDNoritsuguTTakaiwaM. Development of pneumatic lower limb power assist wear driven with wearable air supply system. In: Proceedings of the IEEE/RSJ international conference on intelligent robots and systems, Tokyo, Japan, 3–7 November 2013. New York: IEEE.
31.
ZhangXGuoQZhaoC. Development of a lower extremity exoskeleton suit actuated by hydraulic. In: Proceedings of the international conference on mechatronics and automation (ICMA), Chengdu, China, 5–8 August 2012. New York: IEEE.
32.
CaoHLingZZhuJ. Design frame of a leg exoskeleton for load-carrying augmentation. In: Proceedings of the IEEE international conference on robotics and biomimetics (ROBIO), Guilin, China, 19–23 December 2009. New York: IEEE.
33.
McDaidAKoraKXieS. Human-inspired robotic exoskeleton (HuREx) for lower limb rehabilitation. In:Proceedings of the 2013 IEEE international conference on mechatronics and automation (ICMA), Takamatsu, Japan, 4–7 August 2013. New York: IEEE.
34.
SergeyevAAlarajeNSeidelC. Design of a pneumatically powered wearable exoskeleton with biomimetic support and actuation. In: Proceedings of the 2013 IEEE aerospace conference, Big Sky, MT, 2–9 March 2013. New York: IEEE.
35.
MorichikaTKikkawaFOyamaO. Development of walking assist equipment with pneumatic cylinder. In: Proceedings of the SICE annual conference, Takamatsu, Japan, 17–20 September 2007. New York: IEEE.
36.
TengCWongZTehW. Design and development of inexpensive pneumatically-powered assisted knee-ankle-foot orthosis for gait rehabilitation-preliminary finding. In: Proceedings of the 2012 international conference on biomedical engineering (ICoBE), Penang, Malaysia, 27–28 February 2012. New York: IEEE.
37.
CelebiBYalcinMPatogluV.AssistOn-Knee: a self-aligning knee exoskeleton. In: Proceedings of the 2013 IEEE/RSJ international conference on intelligent robots and systems (IROS), Tokyo, Japan, 3–7 November 2013. New York: IEEE.
38.
YuHHuangSThakorNV. A novel compact compliant actuator design for rehabilitation robots. In: Proceedings of the 2013 IEEE international conference on rehabilitation robotics (ICORR), Seattle, WA, 24–26 June 2013. New York: IEEE.
39.
KaravasNAjoudaniATsagarakisN. Tele-impedance based stiffness and motion augmentation for a knee exoskeleton device. In: Proceedings of the 2013 IEEE international conference on robotics and automation (ICRA), Karlsruhe, 6–10 May 2013. New York: IEEE.
40.
CaiVADBidaudPHaywardV. Self-adjusting, isostatic exoskeleton for the human knee joint. In: Proceedings of the 2011 annual international conference of the IEEE engineering in medicine and biology society (EMBC), Boston, MA, 30 August–3 September 2011. New York: IEEE.
41.
WangD-hGuoJLeeK-M. An adaptive knee joint exoskeleton based on biological geometries. In: Proceedings of the 2011 IEEE international conference on robotics and automation (ICRA), Shanghai, China, 9–13 May 2011. New York: IEEE.
42.
WalkerPSKurosawaHRovickJS. External knee joint design based on normal motion. J Rehabil Res Dev1985; 22(1): 9–22.
43.
BertomeuJMBLoisJMBGuillemRB. Development of a hinge compatible with the kinematics of the knee joint. Prosthet Orthot Int2007; 31(4): 371–383.
44.
KiguchiKImadaY. EMG-based control for lower-limb power-assist exoskeletons. In: Proceedings of the IEEE workshop on robotic intelligence in informationally structured space, Nashville, TN, 30 March–2 April 2009. New York: IEEE.
45.
LiZWangBSunF. sEMG-based joint force control for an upper-limb power-assist exoskeleton robot. IEEE J Biomed Health Inf2014; 18(3): 1043–1050.
46.
HeHKiguchiK. A study on EMG-based control of exoskeleton robots for human lower-limb motion assist. In: Proceedings of the ITAB 2007 6th international special topic conference on information technology applications in biomedicine, Tokyo, Japan, 8–11 November 2007. New York: IEEE.
47.
HayashiTKawamotoHSankaiY. Control method of robot suit HAL working as operator’s muscle using biological and dynamical information. In: Proceedings of the 2005 IEEE/RSJ international conference on intelligent robots and systems (IROS 2005), Edmonton, AB, Canada, 2–6 August 2005. New York: IEEE.
48.
HayashiYKiguchiK.A lower-limb power-assist robot with perception-assist. In: Proceedings of the 2011 IEEE international conference on rehabilitation robotics (ICORR), Zurich, 29 June–1 July 2011. New York: IEEE.
49.
Sylos-LabiniFLa ScaleiaVd’AvellaA. EMG patterns during assisted walking in the exoskeleton. Front Hum Neurosci2014; 8: 423.
50.
IkeharaTNagamuraKUshidaT. Development of closed-fitting-type walking assistance device for legs and evaluation of muscle activity. In: Proceedings of the IEEE international conference on rehabilitation robotics, Zurich, 29 June–1 July 2011. New York: IEEE.
51.
NakamuraTSaitoKWangZ. Realizing model-based wearable antigravity muscles support with dynamics terms. In: Proceedings of the 2005 IEEE/RSJ international conference on intelligent robots and systems (IROS 2005), Edmonton, AB, Canada, 2–6 August 2005. New York: IEEE.
52.
KongKJeonD.Design and control of an exoskeleton for the elderly and patients. IEEE/ASME T Mech2006; 11(4): 428–432.
53.
FleischerCHommelG. Calibration of an EMG-based body model with six muscles to control a leg exoskeleton. In: Proceedings of the IEEE international conference on robotics and automation (ICRA), Roma, 10–14 April 2007. New York: IEEE.
54.
HyunBSongTHwangS. EMG-based neural networks for muscle torque estimation. In: Proceedings of the 11th annual conference of the international FES society, Miyagi-Zao, Japan, 12–15 September 2006, http://ifess.org/proceedings/IFESS2006/IFESS2006_083_Hyun.pdf
55.
NakamuraTSaitoKKosugeK. Control of wearable walking support system based on human-model and GRF. In: Proceedings of the IEEE international conference on robotics and automation, Barcelona, 18–22 April 2005. New York: IEEE.
56.
KimKYuC-HJeongG-Y. Analysis of the assistance characteristics for the knee extension motion of knee orthosis using muscular stiffness force feedback. J Mech Sci Technol2013; 27(10): 3161–3169.
57.
KimKKimJ-JKangS-R. Analysis of the assistance characteristics for the plantarflexion torque in elderly adults wearing the powered ankle exoskeleton. In: Proceedings of the 2010 international conference on control automation and systems (ICCAS), Gyeonggi-do, Korea, 27–30 October 2010. New York: IEEE.
58.
NietertM.Das Kniegelenk des Menschen als biomechanisches Problem. Biomed Tech1977; 22(1–2): 13–21.
59.
FullerJLiuL-JMurphyM. A comparison of lower-extremity skeletal kinematics measured using skin-and pin-mounted markers. Hum Movement Sci1997; 16(2): 219–242.
60.
MüllerRHielscherJBlockJ. Entwicklung einer verbesserten Kniekinematik zur Reduktion von Scher-kräften in passiver Kniegelenksorthese. In: Proceedings of the 8th anniversary of the German society of biomechanics (8 Jahrestagung der DGfB), Neu-Ulm, 15–17 May 2013. Ulm: Universitätsklinikum Ulm
61.
HermesHFreriksBMerlettiR.European recommendations for surface ElectroMyoGraphy (SENIAM). Torino: CLUT, 2000.
62.
HielscherJMeissTWerthschützkyR. Novel approach for estimating muscular activity using mechanical effects on the human thigh as an alternative to EMG. In: Proceedings of the 46th annual conference of the DGBMT, Jena, 17–19 September 2012. Berlin: De Gruyter.
63.
KadabaMPRamakrishnanHWoottenM.Measurement of lower extremity kinematics during level walking. J Orthop Res1990; 8(3): 383–392.
64.
NellesO. Orthonormal basis functions for nonlinear system identification with local linear model trees (LOLIMOT). In: Proceedings of the IFAC symposium on system identification, Kitakyushu, Japan, 8–11 July 1997. Amsterdam: Elsevier.
65.
GrünM.Regelungstechnische Aspekte bei aktiven Knieorthesen zur Mobilitätsunterstützung älterer Menschen. PhD Dissertation, TU Darmstadt, Darmstadt, 2014.
