Design and Experimental Research of 3-RRS Parallel Ankle Rehabilitation Robot

Abstract

The ankle is a crucial joint that supports the human body weight. An ankle sprain will adversely affect the patient’s daily life, so it is of great significance to ensure its strength. To help patients with ankle dysfunction to carry out effective rehabilitation training, the bone structure and motion mechanism of the ankle were analyzed in this paper. Referring to the configuration of the lower-mobility parallel mechanism, a 3-RRS (R and S denote revolute and spherical joint respectively) parallel ankle rehabilitation robot (PARR) was proposed. The robot can realize both single and compound ankle rehabilitation training. The structure of the robot was introduced, and the kinematics model was established. The freedom of movement of the robot was analyzed using the screw theory, and the robot kinematics were analyzed using spherical analytics theory. A circular composite rehabilitation trajectory was planned, and the accuracy of the kinematics model was verified by virtual prototype simulation. The Multibody simulation results show that the trajectory of the target point is basically the same as the expected trajectory. The maximum trajectory error is about 2.5 mm in the simulation process, which is within the controllable range. The experimental results of the virtual prototype simulation show that the maximum angular deflection error of the three motors is 2° when running a circular trajectory, which meets the experimental requirements. Finally, a control strategy for passive rehabilitation training was designed, and the effectiveness of this control strategy was verified by a prototype experiment.

Design of integral backstepping controller - sliding mode along with admittance controller of knee joint robot in the presence of noise

“…1 * Mostafa Jalalnezhad, Kharazmi University (Khu), mostafajalalneghad@yahoo.com, Std_mostafajalalnezh@khu.ac.ir 1 Xiamen Academy of Arts and Design, Fuzhou University, Xiamen，China, 576079447@qq.com 2 Luting Xia, Zhejiang Gongshang University Hangzhou College of Commerce, Hangzhou， China, Xgirl0074905@qq.com ,Corresponding Author: Xgirl0074905@qq.com 3 Zhao Ruoyi, Department of Art Design, Zhejiang Gongshang University, Hangzhou, China, Email: zhaoruoyi208@zjgsu.edu.cn * Mostafa Jalalnezhad, Kharazmi University (Khu), mostafajalalneghad@yahoo.com, Std_mostafajalalnezh@khu.ac.ir 1 Xiamen Academy of Arts and Design, Fuzhou University, Xiamen，China, 576079447@qq.com 2 Luting Xia, Zhejiang Gongshang University Hangzhou College of Commerce, Hangzhou， China, Xgirl0074905@qq.com ,Corresponding Author: Xgirl0074905@qq.com 3 Zhao Ruoyi, Department of Art Design, Zhejiang Gongshang University, Hangzhou, China, Email: zhaoruoyi208@zjgsu.edu.cn 4 Charles Shieh, International association of organizational innovation, FL, USA, Email: charles@iaoiusa.org 13 Figure 13. Control signal of sliding-mode feedback controller in the presence of noise In the following, the way the robot follows the path designed by the physiotherapist has been checked in both controllers, due to the almost similar behavior of the controllers in following the designed path, in order to better compare them with each other, the error of following the path is also given.…”

“…Using a rehabilitation robot can not only relieve doctors from the heavy burden of training, but it can also be useful in evaluating the improvement of patients by analyzing the data recorded in the training process. Due to its advantages in terms of accuracy and reliability, rehabilitation robots are able to provide two useful methods to improve outcomes after stroke or surgery [4]. Currently, the amount of use of robots, whether industrial or service, in a country is directly related to the level of development and progress of that country in various fields.…”

Type Synthesis of Self-Alignment Parallel Ankle Rehabilitation Robot with Suitable Passive Degrees of Freedom

“…Other forms of twisting can be obtained using a linear combination of the four twists in Eq. (20). However, (20 the twists after the linear combination must be linearly independent.…”

“…(20). However, (20 the twists after the linear combination must be linearly independent. The case of redundant kinematics in the limb was not considered.…”

“…Jamwal et al [18,19] proposed a lightweight and compliant parallel ARR in which pneumatic muscle actuators were placed parallel to the shinbone of the patient. Zou et al [20] proposed a 3-RRS parallel ARR that could realize single and compound ankle rehabilitation training. Zhang et al [21] and Qian et al [22] developed ARRs driven by pneumatic muscle actuators that could realize changes in motion and dynamic performance by reconfiguring the actuator layouts.…”