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Article
Publication date: 30 October 2020

Gaoxin Cheng, Linsen Xu, Jiajun Xu, Jinfu Liu, Jia Shi, Shouqi Chen, Lei Liu, Xingcan Liang and Yang Liu

This paper aims to develop a robotic mirror therapy system for lower limb rehabilitation, which is applicable for different patients with individual movement disability levels.

Abstract

Purpose

This paper aims to develop a robotic mirror therapy system for lower limb rehabilitation, which is applicable for different patients with individual movement disability levels.

Design/methodology/approach

This paper puts forward a novel system that includes a four-degree-of-freedom sitting/lying lower limb rehabilitation robot and a wireless motion data acquisition system based on mirror therapy principle. The magnetorheological (MR) actuators are designed and manufactured, whose characteristics are detected theoretically and experimentally. The passive training control strategy is proposed, and the trajectory tracking experiments verify its feasibility. Also, the active training controller that is adapt to the human motor ability is designed and evaluated by the comparison experiments.

Findings

The MR actuators produce continuously variable and compliant torque for robotic joints by adjusting excitation current. The reference limb joint position data collected by the wireless motion data acquisition system can be used as the motion trajectory of the robot to drive the affected limb. The passive training strategy based on proportional-integral control proves to have great trajectory tracking performance through experiments. In the active training mode, by comparing the real-time parameters adjustment in two phases, it is certified that the proposed fuzzy-based regulated impedance controller can adjust assistance torque according to the motor ability of the affected limb.

Originality/value

The system developed in this paper fulfills the needs of robot-assisted mirror therapy for hemiplegic patients.

Details

Industrial Robot: the international journal of robotics research and application, vol. 48 no. 2
Type: Research Article
ISSN: 0143-991X

Keywords

Article
Publication date: 7 April 2022

Linhai Zhu, Liu Jinfu, Yujia Ma, Mingliang Bai, Weixing Zhou and Daren Yu

This paper aims to establish a multi-input equilibrium manifold expansion (EME) model for gas turbine (GT). It proposes that the extension of model input dimension is…

Abstract

Purpose

This paper aims to establish a multi-input equilibrium manifold expansion (EME) model for gas turbine (GT). It proposes that the extension of model input dimension is realized based on similarity theory and affine structure in the framework of single-input EME model. The study aims to expand the scope of application of the EME model so that it can be used for the control or fault diagnosis of GTs.

Design/methodology/approach

In this paper, the concepts of corrected equilibrium manifold expansion (CEME) model and multi-cell equilibrium manifold expansion (MEME) model are first proposed. This paper uses theoretical analysis and simulation experiments to demonstrate the effectiveness of the bilayer equilibrium manifold expansion (BEME) model, which is a combination of the CEME and the MEME models. Simulation experiments include confirmatory experiments and comparative experiments.

Findings

The paper provides a new sight into building a multiple-input EME (MI-EME) model for GTs. The proposed method can build an accurate and robust MI-EME model that has superior performance compared with widely used nonlinear models including Wiener model (WM), Hammerstein model (HM), Hammerstein–Wiener model (HWM) and nonlinear autoregressive with exogenous inputs (NARX) network model. In terms of accuracy, the maximum error percentage of the proposed model is just 1.309%, far less than WM, HM and HWM. In terms of the stability of model calculation, the range of the mean error percentage of the proposed model is just a quarter of that of NARX network model.

Originality/value

The paper fulfills the construction of a novel multi-input nonlinear model, which has laid a foundation for the follow-up research of model-based GT fault detection and isolation or GT control.

Details

Aircraft Engineering and Aerospace Technology, vol. 94 no. 8
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 8 February 2021

Jiajun Xu, Linsen Xu, Gaoxin Cheng, Jia Shi, Jinfu Liu, Xingcan Liang and Shengyao Fan

This paper aims to propose a bilateral robotic system for lower extremity hemiparesis rehabilitation. The hemiplegic patients can complete rehabilitation exercise…

Abstract

Purpose

This paper aims to propose a bilateral robotic system for lower extremity hemiparesis rehabilitation. The hemiplegic patients can complete rehabilitation exercise voluntarily with the assistance of the robot. The reinforcement learning is included in the robot control system, enhancing the muscle activation of the impaired limbs (ILs) efficiently with ensuring the patients’ safety.

Design/methodology/approach

A bilateral leader–follower robotic system is constructed for lower extremity hemiparesis rehabilitation, where the leader robot interacts with the healthy limb (HL) and the follow robot is worn by the IL. The therapeutic training is transferred from the HL to the IL with the assistance of the robot, and the IL follows the motion trajectory prescribed by the HL, which is called the mirror therapy. The model reference adaptive impedance control is used for the leader robot, and the reinforcement learning controller is designed for the follower robot. The reinforcement learning aims to increase the muscle activation of the IL and ensure that its motion can be mastered by the HL for safety. An asynchronous algorithm is designed by improving experience relay to run in parallel on multiple robotic platforms to reduce learning time.

Findings

Through clinical tests, the lower extremity hemiplegic patients can rehabilitate with high efficiency using the robotic system. Also, the proposed scheme outperforms other state-of-the-art methods in tracking performance, muscle activation, learning efficiency and rehabilitation efficacy.

Originality/value

Using the aimed robotic system, the lower extremity hemiplegic patients with different movement abilities can obtain better rehabilitation efficacy.

Details

Industrial Robot: the international journal of robotics research and application, vol. 48 no. 3
Type: Research Article
ISSN: 0143-991X

Keywords

Article
Publication date: 25 July 2019

Shuyan Zhao, Hao Chen, Rui Nie and Jinfu Liu

This paper aims to propose a double-sided switched reluctance linxear generator (DSRLG) exclusively for wave power generation. The initial dimensions are given through…

Abstract

Purpose

This paper aims to propose a double-sided switched reluctance linxear generator (DSRLG) exclusively for wave power generation. The initial dimensions are given through design experience and principles. To ameliorate comprehensive performance of the DSRLG, the multi-objective optimization design is processed.

Design/methodology/approach

The multi-objective optimization design of the DSRLG is processed by adopting a modified entropy technique for order of preference by similarity to ideal solution (TOPSIS) algorithm. First, sensitivity analyzes on geometric parameters of the DSRLG are conducted to determine several pivotal geometric parameters as optimization variables. Then, the multi-objective optimization is conducted on the basis of initial dimensions. After determination of synthetical evaluation value of each structure parameter, the best dimension scheme of the DSRLG is concluded.

Findings

After verification by finite element method simulation and dynamic simulation, the final dimension scheme proves to perform better than the initial scheme. Finally, experiments are conducted to verify the accuracy of both the stable finite element DSRLG model and dynamic simulation system model so that the conclusion of this paper proves to be reliable and compelling.

Originality/value

This paper proposes an improved structure of the DSRLG, which is superior for wave power generation. Meanwhile, a novel modified entropy TOPSIS algorithm is applied to the field of electrical machine multi-objective optimal design for the first time.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering , vol. 38 no. 6
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 1 January 2006

Zhang Jinfu, Liu Wei, Qin Weiyang and He Xinsuo

A partial differential equation for elastic vibration of connecting rod of a slider‐crank mechanism is formulated by applying Theorem of Motion of Center of Mass and…

169

Abstract

A partial differential equation for elastic vibration of connecting rod of a slider‐crank mechanism is formulated by applying Theorem of Motion of Center of Mass and viscoelastic model. The partial differential equation is discretized into two second‐order ordinary differential equations by assuming a two‐mode approximation. The two equations are transformed into the first order linear ordinary differential equations with periodical coefficients. Then the stability of elastic vibration of the connecting rod is investigated using Floquet theory. Procedures for predicting the stability are developed. Finally, a case study is analyzed by applying the procedures.

Details

Multidiscipline Modeling in Materials and Structures, vol. 2 no. 1
Type: Research Article
ISSN: 1573-6105

Keywords

Article
Publication date: 27 May 2020

Yingwei Liu, Tao Wang, Ling Zhou and Chunyan Nie

The essence of “Chinese element” has been pinpointed as the representation of national cultural archetype resource of China, which reflects to the overall power…

Abstract

Purpose

The essence of “Chinese element” has been pinpointed as the representation of national cultural archetype resource of China, which reflects to the overall power enhancement of China. Applying the Chinese national cultural archetype resource, which will be used for promoting the Chinese Brand internationalization, aims for the consumers' approval with the hope of integrating and spreading the unique cultural advantage of Chinese brand. The recognizing of Chinese brand's cultural archetype in this paper has constituted the basis of Chinese brand's cultural archetype strategy.

Design/methodology/approach

Based on the Grounded Theory, this paper has collected and analyzed the value symbols, character images and theme stories of Chinese narrative advertisements and constructed the cultural archetype framework of Chinese brands. This paper makes a comprehensive application of Charmaz's constructivist analysis and the main axis analysis and inspection method advocated by Strauss, with the aim of building a more objective and systematic theoretical framework for the Chinese brand cultural archetype.

Findings

In this framework, it revealed: (1) Chinese brand's cultural archetype can be divided into 12 concrete archetypes according to individual's relationship with self, the other, community and nature; (2) Consumers' different ways of self-categorization are attributed as the essential difference among various archetypes. This paper also compared and analyzed the differences between Chinese and Western cultural archetypes from three perspectives, formation of social structure, pedigree of myth and character's feature.

Originality/value

This paper has certain innovative significance to the theoretical construction of the archetype of Chinese brand culture. First, based on the cultural perspective, this paper applied the cultural psychological connotation of archetype to the brand research across culture, which is more conducive to the researchers' investigation of the cultural psychology of consumers in the cross-cultural context? Second, based on the identification and comparative study of Chinese brand culture archetype, it provides a new expansion and supplement for the research on brand internationalization and globalization in emerging countries.

Details

Journal of Contemporary Marketing Science, vol. 3 no. 1
Type: Research Article
ISSN: 2516-7480

Keywords

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