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. 2022 May 30:16:790020.
doi: 10.3389/fnbot.2022.790020. eCollection 2022.

Semiactive Knee Orthotic Using a MR Damper and a Smart Insole to Control the Damping Force Sensing the Plantar Pressure

David Alvarado-Rivera  1 , Paola A Niño-Suárez  1 , Leonel G Corona-Ramírez  2
Affiliations

Semiactive Knee Orthotic Using a MR Damper and a Smart Insole to Control the Damping Force Sensing the Plantar Pressure

David Alvarado-Rivera et al. Front Neurorobot. .

Abstract

This work presents the development of semiactive knee orthosis prototype that focus to absorb the forces and impacts in this joint during the human gait. This prototype consists of three subsystems: the first is a wireless and portable system capable of measuring the ground reaction forces in the stance phase of the gait cycle, by means of an instrumented insole with force sensing resistors strategically placed on the sole of the foot, an electronic device allows processing and transmit this information via Bluetooth to the control system. The second is a semiactive actuator, which has inside a magnetorheological fluid, highlighting its ability to modify its damping force depending on the intensity of the magnetic field that circulates through the MR fluid. It is regulated by a Proportional Derivative (PD) controller system according to the values of plantar pressure measured by the insole. The third component is a mechanical structure manufactured by 3D printing, which adapts to the morphology of the human leg. This exoskeleton is designed to support the forces on the knee controlling the action of the magnetorheological actuator by ground reaction forces. The purpose of this assistance system is to reduce the forces applied to the knee during the gait cycle, providing support and stability to this joint. The obtained experimental results indicate that the device fulfills the function by reducing 12 % of the impact forces on the user's knee.

Keywords: GRF; MR damper; PD control; knee orthotic; smart insole.

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Conflict of interest statement

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Figures

Figure 1
Figure 1
Composition of the orthosis using a semi-active actuator.
Figure 2
Figure 2
Human gait cycle (Cheze et al., 2019).
Figure 3
Figure 3
Instrumented insole, CAD design, and manufacturing. (A) CAD model of the instrumented insole. (B) Lower base for silicone casting. (C) Bottom layer of silicone casting. (D) Profile for insole thickness. (E) Top layer of silicone casting. (F) Silicone insole. (G) Insole covering.
Figure 4
Figure 4
FSR sensors characterization. (A) FSR sensor signal conditioning circuit. (B) FSR-402 sensors characteristic curve.
Figure 5
Figure 5
Data acquisition system. (A) DAS block diagram. (B) Hardware Architecture. (C) PCB CAD design.
Figure 6
Figure 6
Data processed using the DAS. (A) Data from each sensor placed on the instrumented insole. (B) Ground reaction forces obtained with SAD.
Figure 7
Figure 7
Block diagram of the designed control system.
Figure 8
Figure 8
Diagrams for the configuration of semiactive orthosis. (A) Isolated mass SDOF system configuration. (B) Buc-Wen model diagram for MR damper.
Figure 9
Figure 9
MR Damper simulation. (A) Bouc-Wen model block diagram for MR actuator. (B) Simulation graphs of the RD-8040-1 actuator model.
Figure 10
Figure 10
Simulation of single degree of freedom system. (A) Block diagram of the SDOF system. (B) Simulation of the SDOF system.
Figure 11
Figure 11
Proportional-derivative controller. (A) PD controller block diagram. (B) Response of the system with PD controller to the step function. (C) Simulation of the PD controller using a sinusoidal signal.
Figure 12
Figure 12
CAD model of the semiactive orthosis. (A) Assembly of the orthosis prototype structure. (B) Top support. (C) Medium support. (D) Bottom support. (E) Upper support bar. (F) Lower support bar. (G) Exploding parts of the orthosis.
Figure 13
Figure 13
Stress analysis on ANSYS®. (A) Von Mises stresses obtained in the structure of the orthosis in a vertical position. (B) Von Mises stresses obtained in the structure of the orthosis in a 95° position. (C) Total displacement of the structure.
Figure 14
Figure 14
3D printed orthosis structure placed on the leg.
Figure 15
Figure 15
Semi-active orthosis evaluation. (A) Samples obtained while standing. (B) Samples obtained during the gait cycle. (C) Semiactive orthosis prototype behavior.
See this image and copyright information in PMC

References

    1. Ahmadkhanlou F. (2008). Design, Modelign and Control of Magnetorhelogical Fluid-Based Force Feedback Dampers for Telerobotic Systems. Columbus, “OH: The Ohio State University”.
    1. Arias-Montiel M., Florean H., Fransisco-Agustín E. (2015). “Experimental characterization of magnetorheological damper by a polynomial model,” in International Conference on Mechatronics, Electronics and Automotive Engineering (Oaxaca: ), 128–133.
    1. Ávila Chaurand R., Prado León R., González Muñoz E. L. (2007). Dimensiones Antropométricas de Población Latinoamericana: México, Cuba, Colombia, Chile. Guadalajara: Universidad de Guadalajara, Centro Universitario de Arte, Arquitectura y Diseño, División de Tecnología y Procesos, Departamento de Producción y Desarrollo, Centro de Investigaciones en Ergonomía.
    1. Bulea T. C., Kobetic R., Curtis To S., Musa Audu L., John Schnellenberger R., Triolo R. J. (2012). A variable impedance knee mechanism for controlled stance flexion during pathological gait. IEEE/ASME Trans. Mechatron. 17, 822–832. 10.1109/TMECH.2011.2131148 - DOI
    1. Chen J., Liao W. H. (2006). “A leg exoskeleton utilizing a magnetorheological actuator,” in Proceedings of the 2006 IEEE International Conference on Robotics and Biomimetics (Kunming: ), 824–829.

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