Development of Polymer Optical Fiber Sensors for Lower Limb Exoskeletons Instrumentation

  • Arnaldo G. Leal-Junior
  • Anselmo FrizeraEmail author
  • Carlos Marques
  • Maria José Pontes
Conference paper
Part of the Biosystems & Biorobotics book series (BIOSYSROB, volume 22)


This paper presents the instrumentation of a lower limb exoskeleton with polymer optical fiber (POF) sensors. The robotic device presents a potentiometer and an electronic strain gauge (ESG) for the assessment of angle and human-robot interaction forces, respectively. Such devices are compared with the proposed POF curvature sensor and a POF-based strain gauge (POF-SG). The results show a root mean squared error (RMSE) between the POF curvature sensor and the potentiometer of 1.80° in a measurement ranging from 10° to 80°, whereas a RMSE of 1.31 Nm was obtained between the ESG and POF-SG in a range of 0 to 14 Nm. Such results demonstrate the feasibility of POF sensors as alternative solution for the instrumentation of wearable robots.


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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  • Arnaldo G. Leal-Junior
    • 1
  • Anselmo Frizera
    • 1
    Email author
  • Carlos Marques
    • 2
  • Maria José Pontes
    • 1
  1. 1.Graduate Program of Electrical EngineeringFederal University of Espírito SantoVitóriaBrazil
  2. 2.Instituto de TelecomunicaçõesAveiroPortugal

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