Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2023 Jun 22;23(13):5827.
doi: 10.3390/s23135827.

Development of a Control Strategy in an Isokinetic Device for Physical Rehabilitation

Jorge Andrés Peñaloza-González  1 , Sergey González-Mejía  1 , José Isidro García-Melo  1
Affiliations

Development of a Control Strategy in an Isokinetic Device for Physical Rehabilitation

Jorge Andrés Peñaloza-González et al. Sensors (Basel). .

Abstract

Robotic-assisted rehabilitation is currently being applied to improve the effectiveness of human gait rehabilitation and recover the mobility and strength after a stroke or spinal cord injury; a robotic assistant can allow the active participation of the patient and the supervision of the collected data and decrease the labor required from therapists during the patient's training exercises. The goal of gait rehabilitation with robotic-based assistance is to restore motor function by using diverse control strategies, taking account of the physical interaction with the lower limbs of the patient. Over the last few years, researchers have extracted useful information from the patient's biological signals that can effectively reflect movement intention and muscle activation. One way to evaluate progress in rehabilitation is through isokinetic prototype tests that describe the dynamic characteristics of an isokinetic leg extension device for rehabilitation and control action. These tests use an isokinetic system to assess muscle strength and performance in a patient during isometric or isokinetic contraction. An experimental prototype shown in the following work allows the device's performance to be evaluated in a controlled environment before the patient's use. New features provide a control system that can be teleoperated for distributed structures, enabling the remote operation and management of the device. In order to achieve physical recovery from musculoskeletal injuries in the lower limbs and the reintegration of the affected subject into society as an independent and autonomous individual in their daily activities, a control model that introduces a medical isokinetic rehabilitation protocol is presented, in which the element that carries out such protocol consists of a magnetic particle brake whose control action is strongly influenced by the dynamics of the system when in contact with the end user-specifically, the patient's legs in the stretch from the knee to the ankle. The results of these tests are valuable for health professionals seeking to measure their patient's progress during the rehabilitation process and determine when it is safe and appropriate to advance in their treatment.

Keywords: dynamic modeling; dynamometry; electric brake control; isokinetic; isokinetic control; rehabilitation.

PubMed Disclaimer

Conflict of interest statement

The authors have no conflict of interest to declare.

Figures

Figure 1
Figure 1
Rehabilitation device configured for a lower limb rehabilitation system from Universidad del Valle: (1) control screen; (2) chassis; (3) emergency; (4) foot pedal; (5) support structure stop; and (6) magnetic brake.
Figure 2
Figure 2
The behavior of the lower limb during extension. (a) Angular position at the knee joint for an uncontrolled extension. A tendency for the linear growth of extension can be observed from 0 radians to approximately 1.5 radians over time. (b) The angular speed at the knee joint during an uncontrolled leg extension. Multiple peaks can be observed during the extension of the leg reaching approximately 1.5 radians per second at the maximum speed segment.
Figure 3
Figure 3
The behavior of the lower limb during extension. (a) Angular position at the knee joint for an ideal controlled extension. A better tendency for linear growth in the extension over time can be observed from 0 rad to approximately 1.5 rad. (b) The angular speed at the knee joint during an ideal controlled leg extension. A linear growth trend in extension speed is observed at the onset of motion, reaching stability at approximately 1.1 rads.
Figure 4
Figure 4
Torques are associated with knee joint extension.
Figure 5
Figure 5
The dynamics of a lower limb during the extension. (a) Torques in the knee joint for maximum extension. (b) Diagram of forces and distances in the human leg.
Figure 6
Figure 6
Presence of the patellar tendon and the separation angle between the tibia and the tendon.
Figure 7
Figure 7
Measurements and distances for calculating Φ measured in radians due to the leg extension. (a) Relation between LT with respect to the leg extension angle. (b) Φ location regarding the tendon length during the leg extension. Variation of Φ according to the leg extension from 0 to 90°.
Figure 8
Figure 8
View of the triangle formed by the patellar tendon at the positions of maximum extension, θ=90° (1.57 radians), and reference flexion, θ=0° (0 radians).
Figure 9
Figure 9
Cartesian components with respect to patellar tendon force.
Figure 10
Figure 10
Reduction of components for human torque calculation.
Figure 11
Figure 11
Average current percentage vs. average torque percentage for a GXFZ-B-6 model [34].
Figure 12
Figure 12
Patient’s leg attached to the rehabilitation device.
Figure 13
Figure 13
Dynamic modeling for the human–machine system in a closed loop.
Figure 14
Figure 14
Control system implemented with proportional and integrative control.
Figure 15
Figure 15
Time response of the dynamic system when controller A is applied.
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

References

    1. Osternig L.R. Isokinetic Dynamometry: Implications for Muscle Testing and Rehabilitation. Exerc. Sport Sci. Rev. 1986;14:45–80. doi: 10.1249/00003677-198600140-00005. - DOI - PubMed
    1. Vidmar M.F., Baroni B.M., Michelin A.F., Mezzomo M., Lugokenski R., Pimentel G.L., Silva M.F. Isokinetic eccentric training is more effective than constant load eccentric training for quadriceps rehabilitation following anterior cruciate ligament reconstruction: A randomized controlled trial. Braz. J. Phys. Ther. 2019;24:424–432. doi: 10.1016/j.bjpt.2019.07.003. - DOI - PMC - PubMed
    1. Sherman W.M., Pearson D., Plyley M., Costill D., Habansky A., Vogelgesang D.A. Isokinetic rehabilitation after surgery: A review of factors which are important for developing physiotherapeutic techniques after knee surgery. Am. J. Sport. Med. 1982;10:155–161. doi: 10.1177/036354658201000307. - DOI - PubMed
    1. Camacho J.A., Chamorro C.D., Sanabria J.A., Caicedo N.G., García J.I. Implementation of a Service-Oriented Architecture for Applications in Physical Rehabilitation. Rev. Fac. Ing. 2017;26:113–121. doi: 10.19053/01211129.v26.n46.2017.7323. - DOI
    1. Delgado G.C., García J.I. Diseño y Construcción de Una Unidad de Rehabilitación de Hombro Teleoperado Que Integra Requerimientos de Diseño Interdisciplinarios. Cali, Colombia, March 2017. [(accessed on 26 May 2023)]. Available online: https://bibliotecadigital.univalle.edu.co/bitstream/handle/10893/12063/2...