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Article
Publication date: 1 February 2016

Hong Qiao, Chuan Li, Peijie Yin, Wei Wu and Zhi-Yong Liu

Human movement system is a Multi-DOF, redundant, complex and nonlinear system formed by coordinating combination of neural system, bones, muscles and joints, which is robust and…

Abstract

Purpose

Human movement system is a Multi-DOF, redundant, complex and nonlinear system formed by coordinating combination of neural system, bones, muscles and joints, which is robust and has fast response and learning ability. Imitating human movement system can improve robustness, fast response and learning ability of the robots.

Design/methodology/approach

In this paper, we propose a new motion model based on the human motion pathway, especially the information propagation mechanism between the cerebellum and spinal cord.

Findings

The proposed motion model proves to have fast response and learning ability through experiments, which matches the features of human motion.

Originality/value

The proposed model in this paper introduces the habitual theory in kinesiology and neuroscience into robot control, and improves robustness, fast response and learning ability of the robots. This paper proves that introduction of neuroscience has an important guiding significance for precise and adaptive robot control, such as assembly automation.

Details

Assembly Automation, vol. 36 no. 1
Type: Research Article
ISSN: 0144-5154

Keywords

Article
Publication date: 17 March 2022

Chengguo Liu, Ye He, Xiaoan Chen and Hongli Cao

As more and more robots are used in industry, it is necessary for robots to interact with high dynamic environments. For this reason, the purpose of this research is to form an…

Abstract

Purpose

As more and more robots are used in industry, it is necessary for robots to interact with high dynamic environments. For this reason, the purpose of this research is to form an excellent force controller by considering the transient contact force response, overshoot and steady-state force-tracking accuracy.

Design/methodology/approach

Combining the active disturbance rejection control (ADRC) and the adaptive fuzzy PD controller, an enhanced admittance force-tracking controller framework and a well-designed control scheme are proposed. Tracking differentiator balances the contradiction between inertia and jump control signal of the control object. Kalman filter and extended state observer are introduced to obtain purer feedback force signal and uncertainty compensation. Adaptive fuzzy PD controller is introduced to account for transient and steady state performance of the system.

Findings

The proposed controller has achieved successful results through simulation and actual test of 6-axis robot with minimum error.

Practical implications

The controller is simple and practical in real industrial scenarios, where force control by robots is required.

Originality/value

In this research, a new practical force control algorithm is proposed to guarantee the performance of the force controller for robots interacting with high dynamic environments.

Details

Industrial Robot: the international journal of robotics research and application, vol. 49 no. 5
Type: Research Article
ISSN: 0143-991X

Keywords

Article
Publication date: 1 February 2023

Kaixin Li, Ye He, Kuan Li and Chengguo Liu

With the increasing demands of industrial applications, it is imperative for robots to accomplish good contact-interaction with dynamic environments. Hence, the purpose of this…

Abstract

Purpose

With the increasing demands of industrial applications, it is imperative for robots to accomplish good contact-interaction with dynamic environments. Hence, the purpose of this research is to propose an adaptive fractional-order admittance control scheme to realize a robot–environment contact with high accuracy, small overshoot and fast response.

Design/methodology/approach

Fractional calculus is introduced to reconstruct the classical admittance model in this control scheme, which can more accurately describe the complex physical relationship between position and force in the interaction process of the robot–environment. In this control scheme, the pre-PID controller and fuzzy controller are adopted to improve the system force tracking performance in highly dynamic unknown environments, and the fuzzy controller is used to improve the trajectory, transient and steady-state response by adjusting the pre-PID integration gain online. Furthermore, the stability and robustness of this control algorithm are theoretically and experimentally demonstrated.

Findings

The excellent force tracking performance of the proposed control algorithm is verified by constructing highly dynamic unstructured environments through simulations and experiments. In simulations and experiments, the proposed control algorithm shows satisfactory force tracking performance with the advantages of fast response speed, little overshoot and strong robustness.

Practical implications

The control scheme is practical and simple in the actual industrial and medical scenarios, which requires accurate force control by the robot.

Originality/value

A new fractional-order admittance controller is proposed and verified by experiments in this research, which achieves excellent force tracking performance in dynamic unknown environments.

Details

Industrial Robot: the international journal of robotics research and application, vol. 50 no. 3
Type: Research Article
ISSN: 0143-991X

Keywords

Article
Publication date: 5 June 2007

Gao Zhan‐feng, Du Yan‐liang, Sun Bao‐chen and Jin Xiu‐mei

The purpose of this article is to suggest that Fraby‐Perot optic sensor is a practical measurement gage to monitor the strain of great structures such as railway bridges.

1585

Abstract

Purpose

The purpose of this article is to suggest that Fraby‐Perot optic sensor is a practical measurement gage to monitor the strain of great structures such as railway bridges.

Design/methodology/approach

A remote strain monitoring system based on F‐P optic fiber and virtual instrument is designed to monitor the strains of a railway bridge.

Findings

The application results show that the Fraby‐Perot optical fiber sensors can accurately measure strain and they are suitable for the long‐term and automatic monitoring. In addition, the system has several advantages over conventional structural instruments including fast response, ability of both static and dynamic monitoring, absolute measurement, immunity to interferences such as lightning strikes, electromagnetic noise and radio frequency, low attenuation of light signals in long fiber optic cables.

Practical implications

Health monitoring of structures is getting more and more recognition all over the world because it can minimize the cost of reparation and maintenance and ensure the safety of structures. A strain monitoring system based on F‐P optic fiber sensor was developed according to the health monitoring requirements of Wuhu Yangtze River Railway Bridge, which is the first cable‐stayed bridge with a maximum span of 312 m carrying both railway and highway traffic in China. It has run stably in the monitoring field more than two years and fulfilled the monitoring requirement very well. Now the system has been transplanted successfully to the Zhengzhou Yellow Railway Bridge for strain monitoring. So the work can be referenced by other similar health monitoring projects.

Originality/value

Long‐term, real‐time monitoring of strain using FP fiber optic sensors in railway bridge is an innovation. A remote strain data acquisition and real‐time processing are another character of the system. The work studied can be referenced by other structures monitoring, such as tunnel, concrete bridges, concrete and earth dams.

Details

Journal of Quality in Maintenance Engineering, vol. 13 no. 2
Type: Research Article
ISSN: 1355-2511

Keywords

Article
Publication date: 7 October 2013

Tarek Salah Sobh

Anomaly detection of network attacks has become a high priority because of the need to guarantee security, privacy and reliability. This work aims to describe both intelligent…

Abstract

Purpose

Anomaly detection of network attacks has become a high priority because of the need to guarantee security, privacy and reliability. This work aims to describe both intelligent immunological approaches and traditional monitoring systems for anomaly detection.

Design/methodology/approach

Author investigated different artificial immune system (AIS) theories and proposes how to combine different ideas to solve problems of network security domain. An anomaly detection system that applies those ideas was built and tested in a real time environment, to test the pros and cons of AIS and clarify its applicability. Rather than building a detailed signature based model of intrusion detection system, the scope of this study tries to explore the principle in an immune network focusing on its self-organization, adaptive learning capability, and immune feedback.

Findings

The natural immune system has its own intelligent mechanisms to detect the foreign bodies and fight them and without it, an individual cannot live, even just for several days. Network attackers evolved new types of attacks. Attacks became more complex, severe and hard to detect. This results in increasing needs for network defense systems, especially those with ability to extraordinary approaches or to face the dynamic nature of continuously changing network threats. KDD CUP'99 dataset are used as a training data to evaluate the proposed hybrid artificial immune principles anomaly detection. The average cost of the proposed model was 0.1195 where that the wining of KDD99 dataset computation had 0.233.

Originality/value

It is original to introduce investigation on the vaccination biological process. A special module was built to perform this process and check its usage and how it could be formulated in artificial life.

Details

Information Management & Computer Security, vol. 21 no. 4
Type: Research Article
ISSN: 0968-5227

Keywords

Article
Publication date: 26 May 2022

Hao Lu, Shengquan Li, Bo Feng and Juan Li

This paper mainly aims to deal with the problems of uncertainties including modelling errors, unknown dynamics and disturbances caused by load mutation in control of permanent…

Abstract

Purpose

This paper mainly aims to deal with the problems of uncertainties including modelling errors, unknown dynamics and disturbances caused by load mutation in control of permanent magnet synchronous motor (PMSM).

Design/methodology/approach

This paper proposes an enhanced speed sensorless vector control method based on an active disturbance rejection controller (ADRC) for a PMSM. First, a state space model of the PMSM is obtained for the field orientation control strategy. Second, a sliding mode observer (SMO) based on back electromotive force (EMF) is introduced to replace the encode to estimate the rotor flux position angle and speed. Third, an infinite impulse response (IIR) filter is introduced to eliminate high frequency noise mixed in the output of the sliding mode observer. In addition, a speed control method based on an extended state observer (ESO) is proposed to estimate and compensate for the total disturbances. Finally, an experimental set-up is built to verify the effectiveness and superiority of the proposed ADRC-based control method.

Findings

The comparative experimental results show that the proposed speed sensorless control method with the IIR filter can achieve excellent robustness and speed tracking performance for PMSM system.

Research limitations/implications

An enhanced sensorless control method based on active disturbance rejection controller is designed to realize high precision control of the PMSM; the IIR filter is used to attenuate the chattering problem of traditional SMO; this method simplifies the system and saves the total cost due to the speed sensorless technology.

Practical implications

The use of sensorless can reduce costs and be more beneficial to actual industrial application.

Originality/value

The proposed enhanced speed sensorless vector control method based on an ADRC with the IIR filter enriches the control method of PMSM. It can ameliorate system robustness and achieve excellent speed tracking performance.

Article
Publication date: 19 May 2023

Shijie Dai, Shida Li, Wenbin Ji, Ruiqin Wang and Shuyuan Liu

Considering the response lag and viscous slip oscillation of the system caused by cylinder piston friction during automatic polishing of aero-engine blades by a robotic pneumatic…

Abstract

Purpose

Considering the response lag and viscous slip oscillation of the system caused by cylinder piston friction during automatic polishing of aero-engine blades by a robotic pneumatic end-effector, the purpose of this study is to propose a constant force control method with adaptive friction compensation.

Design/methodology/approach

First, the mathematical model of the pneumatic end-effector is established based on the continuous LuGre model, and the static parameters of the LuGre model are identified to verify the necessity of friction compensation. Second, aiming at the problems of difficult identification of dynamic parameters and unmeasurable internal states in the LuGre model, the parameter adaptive law and friction state observer are designed to estimate these parameters online. Finally, an adaptive friction compensation backstepping controller is designed to improve the response speed and polishing force control accuracy of the system.

Findings

Simulation and experimental results show that, compared with proportion integration differentiation, extended state observer-based active disturbance rejection controller and integral sliding mode controller, the proposed method can quickly and effectively suppress the polishing force fluctuation caused by nonlinear friction and significantly improve the blade quality.

Originality/value

The pneumatic force control method combining backstepping control with the friction adaptive compensation based on LuGre friction model is studied, which effectively suppresses the fluctuation of normal polishing force.

Details

Industrial Robot: the international journal of robotics research and application, vol. 50 no. 5
Type: Research Article
ISSN: 0143-991X

Keywords

Article
Publication date: 4 September 2019

Navya Thirumaleshwar Hegde, V.I. George, C. Gurudas Nayak and Kamlesh Kumar

The purpose of this paper is to give reviews on the platform modeling and design of a controller for autonomous vertical take-off and landing (VTOL) tilt rotor hybrid unmanned…

1208

Abstract

Purpose

The purpose of this paper is to give reviews on the platform modeling and design of a controller for autonomous vertical take-off and landing (VTOL) tilt rotor hybrid unmanned aerial vehicles (UAVs). Nowadays, UAVs have experienced remarkable progress and can be classified into two main types, i.e. fixed-wing UAVs and VTOL UAVs. The mathematical model of tilt rotor UAV is time variant, multivariable and non-linear in nature. Solving and understanding these plant models is very complex. Developing a control algorithm to improve the performance and stability of a UAV is a challenging task.

Design/methodology/approach

This paper gives a thorough description on modeling of VTOL tilt rotor UAV from first principle theory. The review of the design of both linear and non-linear control algorithms are explained in detail. The robust flight controller for the six degrees of freedom UAV has been designed using H-infinity optimization with loop shaping under external wind and aerodynamic disturbances.

Findings

This review will act as a basis for the future work on modeling and control of VTOL tilt rotor UAV by the researchers. The development of self-guided and fully autonomous UAVs would result in reducing the risk to human life. Civil applications include inspection of rescue teams, terrain, coasts, border patrol buildings, police and pipelines. The simulation results show that the controller achieves robust stability, good adaptability and robust performance.

Originality/value

The review articles on quadrotors/quadcopters, hybrid UAVs can be found in many literature, but there are comparatively a lesser amount of review articles on the detailed description of VTOL Tilt rotor UAV. In this paper modeling, platform design and control algorithms for the tilt rotor are presented. A robust H-infinity loop shaping controller in the presence of disturbances is designed for VTOL UAV.

Details

International Journal of Intelligent Unmanned Systems, vol. 8 no. 3
Type: Research Article
ISSN: 2049-6427

Keywords

Article
Publication date: 13 April 2015

Dennis Michael Rose and Raymond Gordon

The purpose of this paper is to examine the evidence for age-related changes in cognition and the implications for leadership styles. In particular, a case is argued for…

1451

Abstract

Purpose

The purpose of this paper is to examine the evidence for age-related changes in cognition and the implications for leadership styles. In particular, a case is argued for distributed forms of leadership that encourage contribution across the age spectrum and hierarchical levels.

Design/methodology/approach

This paper takes a conceptual approach, combining the psychology and management literatures in arguing the case for newer leadership forms, appropriate to an ageing workforce.

Findings

Three principal components of intelligence (fluid, and crystallised intelligence and working memory) are considered and it is argued that high levels of fluid intelligence, generally higher in younger employees, should be accessed while being balanced by crystallised intelligence (experience). Distributed leadership has been mainly applied in educational settings. This paper argues for distributed leadership to maximise creativity and innovation.

Practical implications

Leadership forms that maximise creative input from staff across all age levels are likely to contribute to firm innovation and sustainability. Additionally, job satisfaction and turnover among junior staff may be positively influenced through opportunities for greater participation.

Social implications

The elements discussed in this paper address important leadership issues for managing a multigenerational workforce.

Originality/value

Distributed leadership has been discussed in educational and health literatures for some time; however it is only recently that this approach to leadership has appeared in mainstream management literature. The discussion of age-related changes and distributed leadership introduces and important topic for further research in newer forms of leadership.

Details

Journal of Management Development, vol. 34 no. 3
Type: Research Article
ISSN: 0262-1711

Keywords

Article
Publication date: 5 March 2018

Haiying Liu, Xin Jiang, Yazhou Yue and Guangen Gao

The study aims to propose reverse processing solution to improve the performance of strapdown inertial navigation system (SINS) initial alignment and SINS-/global positioning…

260

Abstract

Purpose

The study aims to propose reverse processing solution to improve the performance of strapdown inertial navigation system (SINS) initial alignment and SINS-/global positioning system- (GPS) integrated navigation. The proposed scheme can be well applied in the fields of aircraft and aerospace navigation.

Design/methodology/approach

For the SINS alignment phase, a fast initial alignment scheme is proposed: the initial value of reverse filter is determined by the final result of forward filter, and then, the reverse filter is carried out using the stored data. Multiple iterations are performed until the accuracy is satisfied. For the SINS-/GPS-integrated phase, a forward–reverse navigation algorithm is proposed: first, the standard forward filter is used, and then, the reverse filter is carried out using the initial value determined by the forward filter, and the final fusion results are achieved by the weighted smoothing of the forward and reverse filtering results.

Findings

The simulation and the actual test results show that in the initial alignment stage, the proposed reverse processing method can obviously shorten the SINS alignment time and improve the alignment accuracy. In the SINS-/GPS-integrated navigation data fusion stage, the proposed forward–reverse data fusion processing can, obviously, improve the performance of the navigation solution.

Practical implications

The proposed reverse processing technology has an important application in improving the accuracy of navigation and evaluating the performance of real-time navigation. The proposed scheme can be not only used for SINS-/GPS-integrated system but also applied to other integrated systems for general aviation aircraft.

Originality/value

Compared with the common forward filtering algorithm, the proposed reverse scheme can not only shorten alignment time and improve alignment accuracy but also improve the performance of the integrated navigation.

Details

Aircraft Engineering and Aerospace Technology, vol. 90 no. 2
Type: Research Article
ISSN: 1748-8842

Keywords

1 – 10 of over 47000