Skip to main content
NCBI home page
Springer Nature - PMC COVID-19 Collection logoLink to Springer Nature - PMC COVID-19 Collection
. 2022 Aug 16;106(1):3. doi: 10.1007/s10846-022-01695-0

A Systematic Review of Low-Cost Actuator Implementations for Lower-Limb Exoskeletons: a Technical and Financial Perspective

T Slucock 1,✉
PMCID: PMC9379875  PMID: 35990171

Abstract

A common issue with many commercial rehabilitative exoskeletons and orthoses are that they can be prohibitively expensive for an average individual to afford without additional financial support. Due to this a user may have limited to the usage of such devices within set rehabilitation sessions as opposed to a continual usage. The purpose of this review is therefore to find which actuator implementations would be most suitable for a simplistic, low-cost powered orthoses capable of assisting those with pathologic gait disorders by collating literature from Web of Science, Scopus, and Grey Literature. In this systematic review paper 127 papers were selected from these databases via the PRISMA guidelines, with the financial costs of 25 actuators discovered with 11 distinct actuator groups identified. The review paper will consider a variety of actuator implementations used in existing lower-limb exoskeletons that are specifically designed for the purpose of rehabilitating or aiding those with conditions inhibiting natural movement abilities, such as electric motors, hydraulics, pneumatics, cable-driven actuators, and compliant actuators. Key attributes such as technical simplicity, financial cost, power efficiency, size limitations, accuracy, and reliability are compared for all actuator groups. Statistical findings show that rotary electric motors (which are the most common actuator type within collated literature) and compliant actuators (such as elastic and springs) would be the most suitable actuators for a low-cost implementation. From these results, a possible actuator design will be proposed making use of both rotary electric motors and compliant actuators.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10846-022-01695-0.

Keywords: Actuator, Assistive Devices, Cost, Lower Limb Exoskeleton, Systematic Review, Wearable Robots

Supplementary Information

Below is the link to the electronic supplementary material.

Supplementary file1 (XLSX 83 KB) (83KB, xlsx)

Tom Slucock

received the B.Eng and M.Eng degrees in Electronic and Communications Engineering from the University of Kent, Canterbury, England in 2020. He is now working with the University of Kent on a PhD to develop a low-cost assistive lower-limb exoskeleton for users with pathologic gait disorders. His Research Interests include Robotics, Microcontrollers, and Exoskeletons.

Author’s Contributions

Tom Slucock: Research and Manuscript Compilation.

Declarations

Conflicts of Interest

The Author Declares no Conflicts of Interest.

Ethics Approval

The Author has read and approved this manuscript.

Consent to Participate

Not Applicable.

Consent for Publication

The Author has agreed to publish this manuscript.

Footnotes

Publisher's Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

References

  • 1.Yagn, N: "Apparatus for Walking, Running, Jumping". United States of America Patent 420,179, (1890)
  • 2.Vukobratovic M, Hristic D, Stojiljkovic Z. Development of active anthropomorphic exoskeletons. Med. Biol. Eng. 1974;12(1):66–80. doi: 10.1007/BF02629836. [DOI] [PubMed] [Google Scholar]
  • 3.Specialty Materials Handling Products Operation General Electric Company, Hardiman I Prototype Project. (1968)
  • 4.Zoss, A., Kazerooni, H. Chu, A.: "On the Mechanical Design of the Berkeley Lower Extremity Exoskeleton (BLEEX)," in IEEE/RSJ International Conference on Intelligent Robotics, pp. 3465–3472. (2005)
  • 5.Sankai, Y.:"HAL: Hybrid Assistive Limb based on Cybernics," in Springer Tracts in Advanced Robotics, pp. 25–34. (2007)
  • 6.Stoye, G., Zaranko, B.: "UK Health Spending," The Institute for Fiscal Studies. (2018)
  • 7.Jones, A.: Interviewee, Ectron EksoNR cost. [Interview]. (2021)
  • 8.Centers for Medicare & Medicaid Services: "National Health Expenditures 2019 Highlights," Centers for Medicare and Medicaid Services. (2019)
  • 9.Gonzalez A, Garcia L, Kilby J, McNair P. Robotic Devices for Paediatric rehabilitation: a review of design features. Biomed. Eng. Online. 2021;20(89):1–33. doi: 10.1186/s12938-021-00920-5. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 10.Slucock, T.:"A Systematic Review of Lower-Cost Actuator Implementations for Lower-Limb Exoskeletons - Addendums". [Online]. Available: https://drive.google.com/drive/folders/1VbrkzbnWZbbhKiqB3QxtUqZAcasgIJnX?usp=sharing. (2021). Accessed 17 November 2021
  • 11.Neuhaus, P. D., Noorden, J. H., Craig, T. J., Torres T., Kirschbaum, J., Pratt, J. E.: "Design and Evaluation of Mina a Robotic Orthosis for Paraplegics," in IEEE International Conference of Rehabilitation Robotics. (2011) [DOI] [PubMed]
  • 12.Moog: "BN34 Specifications," [Online]. Available: https://www.moog.com/content/dam/moog/literature/MCG/BN34-BrushlessDCMotorsDtS.pdf. Accessed 22 November 2021
  • 13.Brundu, A.: Interviewee, Moog BN34–25EU-02 Servo Motor Costs. [Interview]. (2021)
  • 14.Marian, P., Danut, I., Nirvana, P., Dorin, P.: "Engineered Devices to Support Stroke Rehabilitation," in 19th International Conference on Control Systems and Computer Science, pp. 289–295. (2013)
  • 15.Omron: "SGDH Sigma-II servo Drive," [Online]. Available: http://www.farnell.com/datasheets/2923102.pdf. Accessed 2021 November 21
  • 16.Omron: "Sigma-II rotary servo motors," [Online]. Available: https://assets.omron.eu/downloads/datasheet/en/v4/i47e_sgm_h-_sigma-ii_rotary_servo_motors_datasheet_en.pdf. Accessed 21 November 2021
  • 17.Lerner ZF, Gasparri GM, Bair MO, Lawson JL, Luque J, Harvey TA, Lerner AT. An Untethered Ankle Exoskeleton Improves Walking Economy in a Pilt Study of Individuals With Cerebral Palsy. IEEE Trans. Neural Syst. Rehabil. Eng. 2018;26(10):1985–1993. doi: 10.1109/TNSRE.2018.2870756. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 18.Maxon: "EC-4pole 22 Ø22 mm, brushless, 90 Watt | High Power," Maxon, [Online]. Available: https://www.maxongroup.com/maxon/view/product/323218. Accessed 21 November 2021
  • 19.Baud, R., Ortlieb, A., Oliver, J., Bouri, M.: "HiBSO hip exoskeleton: Toward a wearable and autonomous design," in MESROB, pp. 185–195. (2016)
  • 20.Maxon: "RE 30 Ø30 mm, Graphite Brushes, 60 Watt," [Online]. Available: https://www.maxongroup.com/medias/sys_master/root/8881622155294/EN-21-148.pdf. Accessed 21 November 2021
  • 21.Maxon: "Screw Drive GP 22 S Ø22 mm, Metric spindle, M6 x 1," [Online]. Available: https://www.maxongroup.com/maxon/view/product/363826. Accessed 08 December 2021
  • 22.Vouga, T., Baud, R., Fasola, J., Bouri, M., Bleuler, H.: "TWIICE - A Lightweight Lower-Limb Exoskeleton for Complete Paraplegics," in IEEE International Conference on Rehabilitaiton Robotics, pp, 1639–1645. (2017) [DOI] [PubMed]
  • 23.Sonceboz: "Brushless - DC Motors 5612," [Online]. Available: https://pdf.directindustry.com/pdf/sonceboz/brushless-dc-motors-5612/14206-588571.html. Accessed 22 November 2021
  • 24.Yang,W., Yang, C.-J., Wei, Q.-X.: "Design of an Anthropomorphic Lower Extremity Exoskeleton with Compatible Joints," in IEEE International Conference on Robotics and Biomimetics, pp. 1374–1379. (2014)
  • 25.Maxon; "EC 90 flat Ø90 mm, brushless, 90 Watt, with Hall sensors," [Online]. Available: https://www.maxongroup.com/maxon/view/product/323772. Accessed 21 November 2021
  • 26.Zhang T, Tran M, Huang H. Design and Experimental Verification of Hip Exoskeleton With Balance Capacities for Walking Assistance. IEEE/ASME Trans. Mechatron. 2018;23(1):274–285. doi: 10.1109/TMECH.2018.2790358. [DOI] [Google Scholar]
  • 27.Minhyung L, Kim J, Hyung S, Lee J, Seo K, Park YJ, Cho J, Choi B-K, Shim Y, Choi H. A Compact Ankle Exoskeleton With a Multiaxis Parallel Linkage Mechanism. IEEE/ASME Trans. Mechatron. 2021;26(1):191–202. doi: 10.1109/TMECH.2020.3008372. [DOI] [Google Scholar]
  • 28.Maxon: "DCX 32 L Ø32 mm, Graphite Brushes, ball bearings," [Online]. Available: https://www.maxongroup.com/maxon/view/product/motor/dcmotor/DCX/DCX32/DCX32L01GBKL470. Accessed 22 November 2021
  • 29.Taylor, G.: Interviewee, ABSSAC SG0504 Costs. [Interview]. (2021)
  • 30.Walsh, C. J., Paluska, D., Pasch, K., Grand, W., Valiente, A., Herr, H.: "Development of a lightweight, underactuated exoskeleton for load-carrying augmentation," in IEEE International Conference on Robotics and Automation, pp. 3485–3491 (2006)
  • 31.Maxon: "RE 40 Ø40 mm, Graphite Brushes, 150 Watt," [Online]. Available: https://www.maxongroup.com/maxon/view/product/motor/dcmotor/re/re40/148866. Accessed 21 November 2021
  • 32.Colombo G, Jorg M, Schrier R, Dietz V. Treadmill training of paraplegic patinets using a robotic orthosis. J. Rehabil. Res. Dev. 2000;37(6):693–700. [PubMed] [Google Scholar]
  • 33.Michimizos, K. P., Krebs, H. I.: "Assist-as-needed in Lower Extremity Robotic Therapy for Children with Cerebral Palsy," in IEEE International Conference on Biomedical Robotics and Biomechatronics, pp. 1081–1086 (2012)
  • 34."EC-4pole 22 Ø22 mm, brushless, 90 Watt | High Power," [Online]. Available: https://www.maxongroup.com/maxon/view/product/327739. Accessed 21 November 2021
  • 35.Kardan I, Akbarzadeh A. Robust output feedback assistive control of a compliantly actuated knee exoskeleton. Robot. Auton. Syst. 2017;98:15–29. doi: 10.1016/j.robot.2017.09.006. [DOI] [Google Scholar]
  • 36.Ortlieb, A., Bouri, M., Baud, R., Bleuler, H.:"An Assistive Lower Limb Exoskeleton for People with Neurological Gait Disorders," in International Conference on Rehabiliation Robotics, pp. 441–446 (2017) [DOI] [PubMed]
  • 37.Maxon: "Planetary Gearhead GP 32 HP Ø32 mm, 4.0 - 8.0 Nm, Metal Version, High Power | High Power," [Online]. Available: https://www.maxongroup.com/maxon/view/product/326671. Accessed 22 November 2021
  • 38.Washabaugh EP, Claflin ES, Gillespie RB, Krishnan C. A Novel Application of Eddy Current Braking for Functional Strength Training During Gait. Ann. Biomed. Eng. 2016;44(9):2760–2773. doi: 10.1007/s10439-016-1553-2. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 39.The Robot Marketplace: "Banebots Gearboxes," [Online]. Available: http://www.robotcombat.com/products/0-P60K-55-0004.html. Accessed 2 December 2021
  • 40.Anonymous-Company: Interviewee, Strain Wave Gear Example Price. [Interview]. (2021)
  • 41.He Y, Li N, Wang C, Xia L-Q, Yong X, Wu X-Y. Development of a novel autonomous lower extremity exoskeleton robot for walking assistance. Front. Inf. Technol. Electron. Eng. 2019;30:318–329. doi: 10.1631/FITEE.1800561. [DOI] [Google Scholar]
  • 42.Felix, P., Figueiredo, J., Santos, C. P., Moreno, J. C.: "Powered Knee Orthosis for Human Gait Rehabilitation: First Advances," in IEEE 5th Portuguese Meeting on Bioengineering, pp. 1–4. (2017)
  • 43.Park, J.-H., Lee, J.-S., Shin, J.-S., Cho, B.-K.: "Design of a Lower Limb Exoskeleotn Including Roll Actuation to Assist Walking and Standing Up," in IEEE-RAS 15th International Conference on Humanoid Robotics (Humanoids), pp. 359–364. (2015)
  • 44.Maxon: "Encoder ENC 16 RIO, 16384 counts per turn, 3-channel, with RS 422 line driver," [Online]. Available: https://www.maxongroup.com/maxon/view/product/575829. Accessed 2 December 2021
  • 45.RLS: " RMB28 Rotary Magnetic Encoder Module," [Online]. Available: https://www.rls.si/eng/rmb28-rotary-magnetic-module?partNumbers=RMB28IC10BS11. Accessed 2 December 2021
  • 46.Mouser Electronics: "HEDL-5640#A13," [Online]. Available: https://www.mouser.co.uk/ProductDetail/Broadcom-Limited/HEDL-5640A13?qs=sGAEpiMZZMuGN2ig0xo6GwpPTpKC14je. Accessed 2 December 2021
  • 47.Emken JL, Wynne JH, Harkema SJ, Reinkensmeyer DJ. A Robotic Device for Manipulating Human Stepping. IEEE Trans. Rob. 2006;22(1):185–189. doi: 10.1109/TRO.2005.861481. [DOI] [Google Scholar]
  • 48.RS: "Models HSR-A and HSR-AM, Models HSR-LA and HSR-LAM," [Online]. Available: https://docs.rs-online.com/1cbb/0900766b80f448f1.pdf. Accessed 13 January 2022
  • 49.Pietrusinski, M., Unluhisarcikli, O., Cajigas, I., Bonato, P.: "Design of Human - Machine Interface and Altering of Pelvic Obliquity with RGR Trainer," in IEEE International Conference on Rehabilitation Robotics, pp. 1–6. (2011) [DOI] [PMC free article] [PubMed]
  • 50.KOMP-ACT: "KLM-40–0F4 KOMP-ACT LINEAR MOTOR," [Online]. Available: https://komp-act.com/wp-content/uploads/2021/06/KLM-40-0F4.pdf. Accessed 16 December 2021
  • 51.Saito, Y., Kikuchi, H., Negoto, H., Oshima, T., Haneyoshi, T., Hatoyama-cho, I., Saitama, H.-G.: "Development of externally powered lower limb orthosis with bilateral-servo actuator," in 9th International Conference on Rehabilitation Robotics, pp. 394–399. (2005)
  • 52.Zoss AB, Kazerooni H, Chu A. Biomechanical Design of the Berkeley Lower Extremity Exoskeleton (BLEEX) IEEE/ASME Trans. Mechatron. 2006;11(2):128–138. doi: 10.1109/TMECH.2006.871087. [DOI] [Google Scholar]
  • 53.Kaminaga, H., Amari, T., Niwa, Y., Nakamura, Y.: "Development of knee power assist using backdrivable electro-hydrostatic actuator," in IEEE/RSJ International Conference on Intelligent Robots and Systems, pp. 5517–5524. (2010)
  • 54.Kim HG, Lee JW, Jang J, Park S, HC Design of an Exoskeleton with minimized energy consumption based on using elastic and dissipative elements. Int. J. Control Autom Syst. 2015;13(2):463–474. doi: 10.1007/s12555-013-0386-0. [DOI] [Google Scholar]
  • 55.Sun M, Ouyang X, Mattila J, Yang H, Hou G. One Novel Hydraulic Actuating System for the Lower-Body Exoskeleton. Chin. J. Mech. Eng. 2021;34(1):1–10. doi: 10.1186/s10033-021-00535-w. [DOI] [Google Scholar]
  • 56.Staman K, Vaele AJ, van der Kooij H. Design, control and evaluation of the Electro-Hydrostatic Actuator, PREHydrA, for Gait Restoration Exoskeleton Technology. IEEE Trans. Med. Robot. Bionics. 2021;3(1):156–165. doi: 10.1109/TMRB.2020.3048224. [DOI] [Google Scholar]
  • 57.Kollmorgen: "AKM Servo Motor Selection Guide," [Online]. Available: https://cdn.kyklo.co/assets/ W1siZiIsIjIwMjEvMDMvMjEvMTIvNTUvMzcvNzY1Mjg2NGItNjIzNi00OWFjLWIyYzMtMGY0OTRmYmU3ZjZkL0tvbGxtb3JnZW4lMjAtJTIwQUtNJTIwc2VyaWVzJTIwLSUyMENhdGFsb2clMjAyMDE3LnBkZiJdXQ?sha=a34ad8186ed4c2fa. Accessed 8 December 2021
  • 58.Minuteman | Empire: "9/16” Heavy Duty, Double Acting, Clevis Mount, 6," [Online]. Available: https://shop.maseas.com/9-16-heavy-duty-double-acting-clevis-mount-6-h9c-6d.html. Accessed 8 December 2021
  • 59.iAutomation: "AKM22C-BNBNC-00," [Online]. Available: https://shop.i-automation.com/products/AKM22C-BNBNC-00. Accessed 8 December 2021
  • 60.Wang B, Liang Y, Xu D, Wang Z, Ji J. Design on Electrohydraulic servo driving system with walking assisting control for lower limb exoskeleton robot. Int J Advanced Robotic Systems. 2021;18(1):1–17. doi: 10.1177/1729881421992286. [DOI] [Google Scholar]
  • 61.H. Wu, A. Kitagawa, H. Tsukagoshi and C. Liu, "Development of a Novel Pneumatic Power Assisted Lower Limb for Outdoor Walking by the Use of a Portable Pneumatic Power Source," in 16th IEEE International Conference on Control Applications, pp. 1291–1296, 2007.
  • 62.Fujikura Composites: "BF Cylinder," [Online]. Available: https://www.fujikura-control.com/english/product_info/index.php/search?cell003=Air+Cylinders&cell004=BF+cylinder&label=1. Accessed 23 November 2021
  • 63.Sato, M., Yagi, E.: "A Study on Power Assist Suit Using Pneumatic Actuators Based on Calculated Retaining Torques for Lift-Up Motion," in SICE Annual Conference, pp. 628–632. (2011)
  • 64.RS: "RS PRO Pneumatic Profile Cylinder 32mm Bore, 200mm Stroke, CDEM Series, Double Acting," [Online]. Available: https://uk.rs-online.com/web/p/pneumatic-piston-rod-cylinders/4802169. Accessed 1 December 2021
  • 65.Li, Y. D., Hsiao-Wekscler, E. T.: "Gait Mode Recognition and Control for a Portable-Powered Ankle Foot Orthosis," in IEEE International Conference on Rehabilitation Robotics, pp. 1–8. (2013) [DOI] [PubMed]
  • 66.Parker: "Pneumatic Rotary Actuators," [Online]. Available: https://www.parker.com/Literature/Pneumatics%20Division%20Europe/PDE-Documents/Cylinders/Parker_Pneumatic_PRO-PRN_Pneumatic_Rotary_Actuators_PDE2502TCUK.pdf. Accessed 8 December 2021
  • 67.Tidyco: "PRN30D-90–45," [Online]. Available: https://tidyco.co.uk/store/parker-hannifin/parker-hannifin-detail.asp?ProductID=PRN30D-90-45. Accessed 21 November 2021
  • 68.Yamada Y, Endo G, Fukushima EF. Pneumatic walking assistive deice for use over long period. Adv. Robot. 2014;28(18):1253–1264. doi: 10.1080/01691864.2014.920722. [DOI] [Google Scholar]
  • 69.Zheng, H., Shen, T., Afsar, M. R., Kang, I., Young, A. J., Shen, X.: "A Semi-Wearable Robotic Device for Sit-to-Stand Assistance," in IEEE 16th International Conference on Rehabilitation Robotics, pp. 204–209. (2019) [DOI] [PubMed]
  • 70.Bimba: "Original Line® Air Cylinder," [Online]. Available: https://www.bimba.com/en/detail/original-line-cylinder?rp=173.5-DPY. Accessed 21 November 2021
  • 71.Yamamoto, S., Miyoshi, T., Komeda, T., Hiramatsu, K., Nakazawa, K., Akai, M.: "Development of Pneumatic Gait Assist System," in IEEE/ICME International Conference on Coplex Medical Engineering, pp. 1337–1340. (2007)
  • 72.Chandrapal, M., Chen, X.: "Intelligent Active Assistive and Resistive Orthotic Device for Knee Rehabilitation," in IEEE International Conference on Control and Automation, pp. 1880–1885. (2009)
  • 73.Park, Y.-L., Chen, B.-R., Young, D., Stirling, L., Wood, R. J., Goldfield, E., Nagpal, R.: "Bio-inspired Active Soft Orthotic Device for Ankle Foot Pathologies," in IEEE/RSJ International Conference on Intelligent Robots and Systems, pp. 4488–4495. (2011)
  • 74.FESTO: "Fluidic muscle DMSP," [Online]. Available: https://www.festo.com/media/pim/555/D15000100140555.PDF?siteUid=fox_gb&siteName=Festo+GB. Accessed 16 December 2021
  • 75.FESTO: "Fluidic muscle," [Online]. Available: https://www.festo.com/gb/en/a/download-document/datasheet/541403/?CallerID=QuickSearch. Accessed 16 December 2021
  • 76.Sasaki, D., Noritsugu, T., Takaiwa, M.: "Development of Pneumatic Lower Limb Power Assist Wear without Exoskeleton," in IEEE/RSJ International Conference on Intelligent Robots and Systems, pp. 1239–1244. (2012)
  • 77.Sasaki, D., Noritsugu, T., Takaiwa, M.: "Development of Pneumatic Lower Limb Power Assist Wear driven with Wearable Air Supply System," in IEEE/RSJ International Conference on Intelligent Robots and Systems, pp. 4440–4445. (2013)
  • 78.Chung, J., Heimgartner, R., O'Neill, C. T., Phipps, N. S., Walsh, C. J.: "ExoBoot, a soft inflatable robotic boot to assist ankle during walking: Design, Characterization, and Preliminary Tests," in 7th IEEE International Conference on Biomedical Robotics and Biomechatronics, pp. 509–516. (2018)
  • 79.Park J, Choi J, Kim SJ, Seo K-H, Kim J. Design of an Inflatable Wrinkle Actuator With Fast Inflation/Deflation Responses for Wearable Suits. IEEE Robot. Autom. Lett. 2020;5(3):3799–3805. doi: 10.1109/LRA.2020.2976299. [DOI] [Google Scholar]
  • 80.Mauer: "EMGR - EAS 90 L4," [Online]. Available: https://www.motor-mauer.de/elektromotor-wechselstrom-lichtstrommotor-emgr-eas90l4-wechselstrommotor-einphasen-230-v-motor-shop-kaufen-1-1-kw-1500-min-1. Accessed 14 December 2021
  • 81.Thalman, C. M., Hertzell, T., Lee, H.: "Toward A Soft Robotic Ankle-Foot Orthosis (SR-AFO) Exosuit for Human Locomotion: Preliminary Results in Late Stance Plantarflexion Assistance," in 3rd IEEE International Conference on Soft Robotics, pp. 801–807 (2020)
  • 82.PAR Group Ltd.: "TPU93 Thermoplastic Polyurethane - Orange BANCOLLAN, Technical Data Sheet," [Online]. Available: https://www.par-group.co.uk/site-content/1/Docs/updates/1-rubber-and-polyurethane/1.26-tpu93-thermoplastic-polyurethane-orange-bancollan-tds.pdf. Accessed 10 December 2021
  • 83.Rockywoods: "200 DENIER COATED OXFORD NYLON FABRIC (SOLD PER YARD)," [Online]. Available: https://www.rockywoods.com/200-Denier-Packcloth-Nylon-Fabric. Accessed 10 December 2021
  • 84.KOMP-ACT: "KDRV-1-MK-X-X Electronic Controller," [Online]. Available: https://komp-act.com/wp-content/uploads/2021/06/KDRV-1-MK-X-X.pdf. Accessed 16 December 2021
  • 85.Chinchwad, Pimpri: Hydraulic Valves, Actuators, and Accessories.
  • 86.iAutomation: "S20260-VTS," [Online]. Available: https://shop.i-automation.com/products/S20260-VTS. Accessed 8 December 2021
  • 87.Adami M, Seibel A. On-Board Pneumatic Pressure Generation Methods for Soft Robotics Applications. Actuators. 2019;8(2):1–35. [Google Scholar]
  • 88.Hussain S, Xie SQ, Jamwal PK, Parsons J. An Intrinsically Compliant Robotic Orthosis for Treadmill training. Med. Eng. Phys. 2012;34(10):1448–1453. doi: 10.1016/j.medengphy.2012.02.003. [DOI] [PubMed] [Google Scholar]
  • 89.Costa, N. R. S., Caldwell, D. G.: "Control of a Biomimetic "Soft-Actuated" Lower Body 10DOF Exoskeleton," in The First IEEE/RAS-EMBS International Conference on Biomedical Robotics and Biomechatronics, pp. 495–501 (2006)
  • 90.Johnson, D. C., Repperger, D. W., Thompson, G.:"Development of a Mobility Assist for the paralyzed, Amputee, and Spastic Patient," in Fifteenth Southern Biomedical Engineering Conference, pp. 67–70 (1996)
  • 91.Gu, Y., Lv, Y., Ma, X., Lu, C.: "Lower-Limb Soft Orthotic Device for Gait Assistance," in 4th Information Technology and Mechatronics Engineering Conference, pp. 894–897. (2018)
  • 92.Sasaki D, Nortisugu T, Takaiwa M. Development of High Contractile Pneumatic Artificial Rubber Muscle for Power Assist Device. J. Robot. Mechatronics. 2012;24(1):150–157. doi: 10.20965/jrm.2012.p0150. [DOI] [Google Scholar]
  • 93.MegaDepot: "STC 2S020–1/8A-3-D-V 2S020 Direct Acting 2 Way SS Solenoid Valve," [Online]. Available: https://megadepot.com/product/stcvalve-2s020-1-8a-3-d-v-2s020-110vac-din-coil-1-8-npt-9mm-direct-acting-2-way-ss-solenoid-valve. Accessed 19 December 2021
  • 94.Wright, L. G. M. A. C. Kathy: Interviewee, Humphrey Enquiry. [Interview]. (2021)
  • 95.ANSgear: "NINJA DURA PRO SLP CARBON FIBER AIR TANK - 68/4500 - BLACKOUT," [Online]. Available: https://www.ansgear.com/Ninja_Dura_Pro_SLP_Carbon_Fiber_Air_Tank_68_4500_p/ninjatankpro-68slpdurablackout.htm. Accessed 19 December 2021
  • 96.DeWALT: "D55146 - 1.6 HP Continuous. 225 PSI, 4.5 Gallon Compressor," [Online]. Available: https://www.dewalt.com/products/storage-and-gear/air-compressors/16-hp-continuous-225-psi-45-gallon-compressor/d55146. Accessed 19 December 2021
  • 97.MAUER: "EMGR 90 L4," [Online]. Available: https://www.motor-mauer.de/elektromotor-wechselstrom-lichtstrommotor-emgr-eas90l4-wechselstrommotor-einphasen-230-v-motor-shop-kaufen-1-1-kw-1500-min-1. Accessed 19 December 2021
  • 98.California Air Tools: "California Air Tools 8010A," [Online]. Available: https://www.californiaairtools.com/ultra-quiet-series-of-air-compressor-contractor-grade/1-0-hp-air-compressors/cat-8010a/. Accessed 19 December 2021
  • 99.Kohki, Nitto: "DAH 110," [Online]. Available: http://www.nitto-kohki.eu/en/products-en/pumps-a-compressors/dc-pumps/item/dah-110.html. [Accessed 19 December 2021
  • 100.TOPSFLO: "TMD41A-A," [Online]. Available: http://www.topsflo.com/mini-diaphragm-pump/tmd45-diaphragm-pump.html#Specifications. Accessed 19 December 2021
  • 101.Dandy, T.: Interviewee, Topsflo Diaphragm Pump. [Interview]. (2021)
  • 102.Kohki, L. L. -. N: Interviewee, DAH 110 Information. [Interview]. (2021)
  • 103.Mooney, L. M., Rouse, E. J., Herr, H. M.: "Autonomous Exoskeleton Reduces Metabolic Cost of Walking," in 36th Annual International Conference of the IEEE Engineering in Medicine and Biology Society, pp. 1–11 (2014) [DOI] [PubMed]
  • 104.Bryan GM, Franks PW, Klein SC, Peuchen RJ, Collins SH. A Hip-knee-ankle exoskeleton emulator for studying gait assistance. Int. J. Robot. Res. 2021;40(4–5):722–746. doi: 10.1177/0278364920961452. [DOI] [Google Scholar]
  • 105.Jin, X., Cui, X., Agrawal, S. K.: "Design of a Cable-driven Active Leg Exoskeleton (C-ALEX) and Gait Training Experiments with Human Subjects," in IEEE International Conference on Robotics and Automation, pp. 5578–5583, 2015.
  • 106.Lee Y, Lee J, Choi B, Lee M, Roh S-G, Kim K, Seo K, Kim Y-J, Shim Y. Flexibile Gait Enhancing Mechatronics System for Lower Limb Assistance (GEMS L-Type) IEEE/ASME Trans. Mechatron. 2019;24(4):1520–1531. doi: 10.1109/TMECH.2019.2922977. [DOI] [Google Scholar]
  • 107.Asbeck, A. T., Dyer, R. J., Larusson, A. F., Walsh, C. J.: "Biologically-inspired Soft Exosuit," in IEEE International Conference on Rehabilitation Robotics, pp. 1–8. (2013) [DOI] [PubMed]
  • 108.Mioskowska, M., Stevenson, D., Onu, M., Trkov, M.: "Compressed Gas Actuated Knee Assistive Exoskeleton for Slip-Induced Fall Prevention During Human Walking," in IEEE/ASME International Conference on Advanced Intelligent Mechatronics, pp. 735–740. (2020)
  • 109.Kong K, Jeon D. Design and Control of an Exoskeleton for the Elderly and Patients. IEEE/ASME Int. Trans. Mechatronics. 2006;11(4):428–432. doi: 10.1109/TMECH.2006.878550. [DOI] [Google Scholar]
  • 110.Schmidt K, Duarte JE, Grimmer M, Alejandro S-P. The Myosuit: Bi-Articular Anti-gravity Exosuit That Reduces Hip Extensor Activity in Sitting Transfers. Front. Neutorobot. 2017;11(57):1–16. doi: 10.3389/fnbot.2017.00057. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 111.M. Gloger, G. Obinata, E. Genda, J. Babjak and Y. Pei, "Active Lower Limb Orthosis with One Degree of Freedom for People with Paraplegia," in International Conference on Rehabilitation Robotics, pp. 258–263, 2017. [DOI] [PubMed]
  • 112.Van den Bogert AJ. Exotendons for Assistance of Human Locomotion. Biomed. Eng. Online. 2003;2(17):1–8. doi: 10.1186/1475-925X-2-17. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 113.Symons, C.: Interviewee, Carl Stahl Sava Industries steel cable 2081 Price. [Interview]. (2021)
  • 114.Garcia, P.: Interviewee, Lexco 415310–00 outer cable Price. [Interview]. (2021)
  • 115.Veneman JF, van der Helm FC, van der Kooij H. A Series Elastic- and Bowden-Cable-Based Actuation System for Use as Torque Actuator in Exoskeleton-Type Robots. Int. J. Robot. Res. 2006;25(3):261–281. doi: 10.1177/0278364906063829. [DOI] [Google Scholar]
  • 116.Veneman JF, Kruidhof R, Hekman EEG, Ekkelenkamp R, Van Asseldonk EHF, van der Kooij H. Design and Evaluation of the LOPES Exoskeleton Robot for Interactive Gait Rehabilitation. IEEE Trans. Neural Syst. Rehabil. Eng. 2007;15(3):379–386. doi: 10.1109/TNSRE.2007.903919. [DOI] [PubMed] [Google Scholar]
  • 117.Maxon: "EC-4pole 30 Ø30 mm, brushless, 200 Watt," [Online]. Available: https://www.maxongroup.com/maxon/view/product/motor/ecmotor/ec4pole/305013. Accessed 21 November 2021
  • 118.Nokon: "Products - Gear Systems," [Online]. Available: http://www.nokon.com/NokonUSA_Products%20(black).htm. Accessed 21 November 2021
  • 119.Maxon: "EC-4pole 30 Ø30 mm, brushless, 200 Watt | High Power," [Online]. Available: https://www.maxongroup.com/maxon/view/product/305015. Accessed 21 November 2021
  • 120.EC-i 40 Ø40 mm, brushless, 70 Watt, with Hall sensors, [Online]. Available: https://www.maxongroup.com/maxon/view/product/449470. Accessed 21 November 2021
  • 121.Maxon: "EC-i 30 Ø30 mm, brushless, 75 W, with Hall sensors | High Torque," [Online]. Available: https://www.maxongroup.com/maxon/view/product/539485. Accessed 21 November 2021
  • 122.Banala SK, Agrawal SK, Fattah A, Krishnamoorthy V, Hsu W-L, Scholz J, Rudolph K. Gravity-Balancing Leg Orthosis and Its Performance Evaluation. IEEE Trans. Rob. 2006;22(6):1228–1239. doi: 10.1109/TRO.2006.882928. [DOI] [Google Scholar]
  • 123.Wiggin, B., Sawicki, G. S., Collins, S. H.: "An Exoskeleton Using Controlled Energy Storage and Release to Aid Ankle Propulsion," in International Conference on Rehabilitation Robotics, pp. 1–5 (2011) [DOI] [PubMed]
  • 124.Ranaweera R, Mann G, Gopura RC. Development of a Passively Powered Knee Exoskeleton for Squat Lifting. J. Robot. Netw. Artif. Life. 2018;5(1):45–51. doi: 10.2991/jrnal.2018.5.1.11. [DOI] [Google Scholar]
  • 125.Zhou T, Xiong C, Zhang J, Chen W, Huang X. Regulating Metabolic Energy Among Joints During Human Walking Using a Multiarticular Unpowered Exoskeleton. IEEE Trans. Neural Syst. Rehabil. Eng. 2021;29:662–672. doi: 10.1109/TNSRE.2021.3065389. [DOI] [PubMed] [Google Scholar]
  • 126.Wu, P., Chen, X., He, Y., Liu, Z.: "Unpowered Knee Exoskeleton during Stair Descent," in The 7th International Conference on Mechatronics and Robotics Engineering, pp. 106–110. (2021)
  • 127.Giovacchini F, Vannetti F, Fantozzi M, Cempini M, Cortese M, Parri A, Tingfang Y, Lefeber D, Vitiello N. A Light-Weight Active Orthosis for Hip movement assistance. Robot. Auton. Syst. 2015;73:123–134. doi: 10.1016/j.robot.2014.08.015. [DOI] [Google Scholar]
  • 128.Maxon: "EC 60 flat Ø60 mm, brushless, 100 Watt, with cover," [Online]. Available: https://www.maxongroup.com/maxon/view/product/motor/ecmotor/ecflat/ecflat60/408057. Accessed 18 December 2021
  • 129.Kai, Y., Kitaguchi, S., Shotaro, K., Zhang, W., Tomizuka, M.: "Development of a Rehabilitation Robot Suit with Velocity and Torque-based Mechanical Safety Devices," in IEEE/RSJ International Conference on Intelligent Robots and Systems, pp. 1380–1385. (2014)
  • 130.Maxon: "RE 40 Ø40 mm, Graphite Brushes, 150 Watt," [Online]. Available: https://www.maxongroup.com/maxon/view/product/148867. Accessed 18 December 18
  • 131.MiSUMi: "Round Wire Coil Springs/Deflection 45%/I.D. Referenced (VUR8–20)," [Online]. Available: https://uk.misumi-ec.com/vona2/detail/110302604640/?HissuCode=VUR8-20. Accessed 8 December 2021
  • 132.Alouane MA, Huo W, Rifai H, Amirat Y, Mohammed S. Hybrid FES-Exoskeleton Controller to Assist Sit-To-Stand Movement. IFAC-PapersOnLine. 2019;51(34):296–301. doi: 10.1016/j.ifacol.2019.01.032. [DOI] [Google Scholar]
  • 133.Nikitczuk, J., Weinburg, B., Mavroidis, C.: "Rehabilitative Knee Orthosis Driven by Electro-Rheological Fluid Based Actuators," in IEEE International Conference on Robotics and Automation, pp. 2283–2289. (2005)
  • 134.Zite, J. L., Ahmadkhanlou, F., Neelakantan, V. A., Washington, G. N.: "A Magnetorheological fluid based orthopedic active knee brace," in Smart Structures and Materials 2006: Industrial and Commercial Applications of Smart Structures Technologies, pp. 1–10. (2006)
  • 135.Li Y, Hashimoto M. Design and prototyping of a novel lightweight walking assist wear using PVC gel soft actuators. Sens. Actuators. 2016;239:26–44. doi: 10.1016/j.sna.2016.01.017. [DOI] [Google Scholar]
  • 136.Cheng, C.-Y., Okamoto, S., Li, P., Akiyama, Y., Qiu, C., Yamada, Y.: "Encouragement of Squat-Lifting: Feasability Study of a Highly Usable Passive Knee Assistive Device," in International Symposium on System Integration, pp. 504–508. (2020)
  • 137.Yoshimi: "Shape memory alloy / taper wire φ1.5–0.7 × 300mm," [Online]. Available: https://www.yoshimi-inc.com/shopbrand/ct32/. Accessed 21 November 2021
  • 138.Mueller Sports Medicine: "Self-Adjusting™ Hinged Knee Brace," [Online]. Available: https://www.muellersportsmed.com/b2c-us/en/Open-Catalog/By-Sport/Gymnastics/SELF-ADJUSTING-HINGED-KNEE-BRACE-OSFM/p/6455. Accessed 21 November 2021
  • 139.Yoshizawa, N.: "Powered AFO for Achilles Tendon Rupture," in 30th Annual International IEEE EMBS Conference, pp. 4250–4253. (2008) [DOI] [PubMed]
  • 140.Washabaugh EP, Krishnan C. A Wearable Resistive Robot Facilitates Locomotor Adaptions during Gait. Resorative Neurol. Neurosci. 2018;36(2):215–223. doi: 10.3233/RNN-170782. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 141.K&J Magnetics, Inc.: "DX04B-N52," [Online]. Available: https://www.kjmagnetics.com/proddetail.asp?prod=DX04B-N52. Accessed 21 November 2021
  • 142.Chaichaowarat, R., Macha, V., Wannasuphoprasit, W.: "Passive Knee Exoskeleton Using Brake Torque to Assist Stair Ascent," in IEEE Region 10 Conference, pp. 1165–1170 (2020)
  • 143.Misumi, "Warner series brake (Sinfonia Technology) (PB-260/FMS-AG)," [Online]. Available: https://us.misumi-ec.com/vona2/detail/221004995844/?HissuCode=PB-260%2fFMS-AG. Accessed 21 November 2021
  • 144.Mankala, K. K., Banala, S. K., Agrawal, S. K.: "Passive Swing Assistive Exoskeletons for Motor-Incomplete Spinal Cord Injury Patients," in IEEE International Conference on Robotics and Automation, pp. 3761–3766. (2007)
  • 145.Jin, S., Guo, S., Hashimoto, K., Xiong, X., Yamamoto, M.: "A Soft Wearable Robotic Suit for Ankle and Hip Assistance a Preliminary Study," in 40th Annual International Conference of the IEEE Engineering in Medicine and Biology Society, pp. 1867–1870. (2018) [DOI] [PubMed]
  • 146.Pratt, G. A., Williamson, M. M.: "Series Elastic Actuators," in IEEE/RSJ International Conference on Intelligent Robots and Systems. Human Robot Interaction and Cooperative Robots, pp. 399–406. (1995)
  • 147.Madden JDW, Vandesteeg NA, Anquetil PA, Madden PGA, Takshi A, Pytel RZ, Lafontaine SR, Wieringa PA, Hunter IW. Artificial Muscle Technology: Physical Priciples and Naval Prospects. IEEE J. Oceanic Eng. 2004;29(3):706–728. doi: 10.1109/JOE.2004.833135. [DOI] [Google Scholar]
  • 148.Allen DP, Little R, Laube J, Warren J, Voit W, Gregg RD. Towards an ankle-foot orthosis powered by a dielectric elastomer actuator. Mechatronics. 2021;76(102551):1–13. [Google Scholar]
  • 149.Moltedo, M., Bacek, T., Junius, K., Vanderborght, B., Lefeber, D.: "Mechanical Design of a Lightweight Compliant and Adaptable Active Ankle Foot Orthosis," in IEEE RAS/EMBS International Conference on Biomedical Robotics and Biomechatronics, pp. 1224–1229 (2016)
  • 150.SODEMANN Industrial Springs: "Compression Springs | Produced in Stainless Steel," SODEMANN, [Online]. Available: https://www.industrial-springs.com/products/compression-springs/range-a-b-stainless-steel?a_004=29315_29315&a_006=33271_33284. Accessed 06 September 2021
  • 151.Malkawi S, Al-Nimr M, Azizi D. A multi-criteria optimization analysis for Jordan's energy mix. Energy. 2017;127:680–696. doi: 10.1016/j.energy.2017.04.015. [DOI] [Google Scholar]
  • 152.Pinto D, Garnier M, Baras J, Chang S-H, Charlifue S, Field-Fote E, Furbish C, Tefertiller C, Mummidisetty CK, Taylor H, Jayaraman A, Heinemann AW. Budget impact analysis of robotic exoskeleton use for locomotor training following spinal cord injury in four SCI Model Systems. J. Neuroeng. Rehabil. 2020;17(4):1–13. doi: 10.1186/s12984-019-0639-0. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 153.Brancato EL. Estimation of Lifetime Expectancies of Motors. IEEE Electr. Insul. Mag. 1992;8(3):5–13. doi: 10.1109/57.139066. [DOI] [Google Scholar]
  • 154.Maxon: "Technology - short and to the point," November 2014. [Online]. Available: https://www.maxongroup.com/medias/sys_master/root/8815461597214/DC-Technology-short-and-to-the-point-14-EN-30-31.pdf?attachment=true. Accessed 15 April 2022
  • 155.Woo S-W. Estimating the Lifetime of the Pneumatic Cylinder in Machine Tool Subjected to Repetitive Pressure Loading. J. US-China Public Adm. 2018;15(5):221–238. [Google Scholar]
  • 156.Bimba: "Cylinder Life Expectancy," May 2012. [Online]. Available: https://airinc.net/wp-content/uploads/2014/08/Original-Line-Cylinder_Life_Expectancy-1.pdf. Accessed 15 April 2022
  • 157.Baldor: "Cog-free Brushless Servo Motors," [Online]. Available: https://literature.puertoricosupplier.com/024/MN23295.pdf. Accessed 27 November 2021
  • 158.Baldor: "Servo, Linear & Motion Control," [Online]. Available: http://www.rgspeed.com/assets/documents/feedback/baldor/servo-linear-and-motion-control.pdf. Accessed 21 November 2021
  • 159.Copley Controls Corp.: "ServoTube Application Guide," [Online]. Available: https://www.actronic-solutions.de/files/actronic/FTPROOT/Servotube-AppGuide.pdf. Accessed 1 December 2021
  • 160.Kollmorgen: [Online]. Available: https://www.kollmorgen.com/sites/default/files/public_downloads/s200_vts_e.pdf. Accessed 8 December 2020
  • 161.Elektromotoren: "Electric Motors," [Online]. Available: https://www.motor-mauer.de/mediafiles/datasheets/EMGR/EMGR-Hauptkatalog.pdf. Accessed 14 December 2021
  • 162.FESTO: "Valve series VOVG," [Online]. Available: https://www.festo.com/cat/en-gb_gb/data/doc_ENUS/PDF/US/VOVG_ENUS.PDF. Accessed 19 December 2021
  • 163.Parker C, Borisoff JF, Mortenson WB, Mattie J. A Survey of stakeholder perspectives on exoskeleton technology. J. Neuroeng. Rehabil. 2014;11(169):1–10. doi: 10.1186/1743-0003-11-169. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 164.Wang, S., Wang, L., Meijneke, C., Asseldonk, E. V., Hoewllinger, T., Cheron, G., Ivanenko, Y., Scaleia, V. L., Sylos-Labini, F., Molinari, M., Tamburella, F., Pisotta, I., Thorsteinsson, F., Ilzkovtiz, M., Gancet, J., Nevatia, Y., Hauffe, R., Zanow F., Van der Kooij, H.: Design and Control of the MINDWALKER Exoskeleton. IEEE Trans. Neural Syst. Rehabil. Eng. 23(2), 277–286 (2015) [DOI] [PubMed]
  • 165.Bartenbach, V., Gort, M., Riener, R.: "Concept and Design of a Modular Lower Limb Exoskeleton," in International Conference on Biomedical Robotics and Biomechatronics, pp. 649–654 (2016)
  • 166.Morichika, T., Kikkawa, F., Oyama, O., Yoshimitsu, T.: "Development of Walking Assist Equipment with Pneumatic Cylinder," in SICE Annual Conference, pp. 1058–1063. (2007)
  • 167.TSI Solutions: "173.5-DPY Bimba 1–1/2" x 3.5" Original Line Cyl," TSI Solutions, [Online]. Available: https://www.tsisolutions.us/itemdetail/?itemCode=173.5-DPY. Accessed 6 September 2021
  • 168.Dan: "Single-Acting Cylinders," Hydraulic Schematic Troubleshooting, 01 June 2018. [Online]. Available: http://www.hydraulicstatic.com/20180601_single-acting-cylinders.html. Accessed 04 Sep 2021
  • 169.Dan: "Double-Acting Cylinder with a Piston Rod on One Side," Hydraulic Schematic Troubleshooting, 09 May 2019. [Online]. Available: http://www.hydraulicstatic.com/20190509_double-acting-cylinder-with-a-piston-rod-on-one-side.html. Accessed 04 September 2021
  • 170.RS: "Bosch Rexroth Fixed Hydraulic Cylinder 100mm Stroke, 2952993400," [Online]. Available: https://uk.rs-online.com/web/p/fixed-hydraulic-cylinders/2638556/. Accessed 08 December 2021
  • 171.HosesDirect: "BLACK COMPRESSED AIR HOSE WITH YELLOW STRIPE 20 BAR AIR HOSE. 15/30/100M COILS," [Online]. Available: https://www.hoses.co.uk/images/datasheets/BYA-6.pdf. Accessed 10 December 2021

Associated Data

This section collects any data citations, data availability statements, or supplementary materials included in this article.

Supplementary Materials

Supplementary file1 (XLSX 83 KB) (83KB, xlsx)

Articles from Journal of Intelligent & Robotic Systems are provided here courtesy of Nature Publishing Group

RESOURCES