Design of a pneumatic actuated ankle-foot orthosis which has talocrural and subtalar joint

Ho Seon Choi, Chang Hee Lee, Yoon Su Baek

Research output: Chapter in Book/Report/Conference proceedingConference contribution

5 Citations (Scopus)


As aging progresses, risk of falls in elderly people increases due to the decreasing the range of motion (RoM) of eversion and the weakening of the plantar flexor. Balance training is performed to reduce the risk of falls and powered ankle-foot orthosis (PAFO) can be utilized in this process. The elderly can conduct training on the narrow roads or on the rugged ground with assistance on rotation of eversion and propulsion by PAFO. However, existing PAFOs were developed just by considering the talocrural joint which make the rotation of sagittal plane of ankle which is called by plantar flexion and dorsiflexion. So, we developed the 2 Degree of Freedom (DoF) PAFO which has the Talocrural and Subtalar joints for frontal plane rotation which is called inversion and eversion. We established the coordinate system and calculated the spatial formulas for talocrural and subtalar joint based on anatomical data. Developed PAFO has the pneumatic artificial muscle (PAM) as an actuator which is controlled by solenoid valve with PWM methods, light-weight 3D printed body and knee orthosis for interfacing with wearer in three area which are thigh, shank and foot. The total weight of developed PAFO is 2. 14kg and it can be 1. 44kg without the weight of knee orthosis (0.7kg). Measurement sensors for PAFO were the absolute encoders to measure the angle of talocrural and subtalar joint, tensile loadcell to measure the magnitude of force from PAM, pressure sensor to measure the pressure of PAM and FSR sensor to judge the phase of the gait cycle. The results of the paper show the validation of design, kinematics and functional capacity for human subject experiments with proportional myoelectric control (PMc) of developed PAFO.

Original languageEnglish
Title of host publication2019 IEEE 16th International Conference on Rehabilitation Robotics, ICORR 2019
PublisherIEEE Computer Society
Number of pages6
ISBN (Electronic)9781728127552
Publication statusPublished - 2019 Jun
Event16th IEEE International Conference on Rehabilitation Robotics, ICORR 2019 - Toronto, Canada
Duration: 2019 Jun 242019 Jun 28

Publication series

NameIEEE International Conference on Rehabilitation Robotics
ISSN (Print)1945-7898
ISSN (Electronic)1945-7901


Conference16th IEEE International Conference on Rehabilitation Robotics, ICORR 2019

Bibliographical note

Publisher Copyright:
© 2019 IEEE.

All Science Journal Classification (ASJC) codes

  • Control and Systems Engineering
  • Rehabilitation
  • Electrical and Electronic Engineering


Dive into the research topics of 'Design of a pneumatic actuated ankle-foot orthosis which has talocrural and subtalar joint'. Together they form a unique fingerprint.

Cite this