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Article
Publication date: 1 July 2006

Nkgatho Sylvester Tlale

In this paper, two omni‐directional mobile vehicles are designed and controlled implementing distributed mechatronics controllers. Omni‐directionality is the ability of mobile…

1541

Abstract

Purpose

In this paper, two omni‐directional mobile vehicles are designed and controlled implementing distributed mechatronics controllers. Omni‐directionality is the ability of mobile vehicle to move instantaneously in any direction. It is achieved by implementing Mecanum wheels in one vehicle and conventional wheels in another vehicle. The control requirements for omni‐directionality using the two above‐mentioned methods are that each wheel must be independently driven, and that all the four wheels must be synchronized in order to achieve the desired motion of each vehicle.

Design/methodology/approach

Distributed mechatronics controllers implementing Controller Area Network (CAN) modules are used to satisfy the control requirements of the vehicles. In distributed control architectures, failures in other parts of the control system can be compensated by other parts of the system. Three‐layered control architecture is implemented for; time‐critical tasks, event‐based tasks, and task planning. Global variables and broadcast communication is used on CAN bus. Messages are accepted in individual distributed controller modules by subscription.

Findings

Increase in the number of distributed modules increases the number of CAN bus messages required to achieve smooth working of the vehicles. This requires development of higher layer to manage the messages on the CAN bus.

Research limitations/implications

The limitation of the research is that analysis of the distributed controllers that were developed is complex, and that there are no universally accepted tool for conducting the analysis. The other limitation is that teh mathematical models of the mobile robot that have been developed need to be verified.

Practical implications

In the design of omni‐directional vehicles, reliability of the vehicle can be improved by modular design of mechanical system and electronic system of the wheel modules and the sensor modules.

Originality/value

The paper tries to show the advantages of distributed controller for omni‐directional vehicles. To the author's knowledge, that is a new concept.

Details

Industrial Robot: An International Journal, vol. 33 no. 4
Type: Research Article
ISSN: 0143-991X

Keywords

Article
Publication date: 20 March 2019

Yanchao Sun, Liangliang Chen and Hongde Qin

This paper aims to investigate the distributed coordinated fuzzy tracking problems for multiple mechanical systems with nonlinear model uncertainties under a directed…

Abstract

Purpose

This paper aims to investigate the distributed coordinated fuzzy tracking problems for multiple mechanical systems with nonlinear model uncertainties under a directed communication topology.

Design/methodology/approach

The dynamic leader case is considered while only a subset of the follower mechanical systems can obtain the leader information. First, this paper approximates the system uncertainties with finite fuzzy rules and proposes a distributed adaptive tracking control scheme. Then, this paper makes a detailed classification of the system uncertainties and uses different fuzzy systems to approximate different kinds of uncertainties. Further, an improved distributed tracking strategy is proposed. Closed-loop systems are investigated using graph theory and Lyapunov theory. Numerical simulations are performed to verify the effectiveness of the proposed methods.

Findings

Based on fuzzy control and adaptive control theories, the desired distributed coordinated tracking control strategies for multiple uncertain mechanical systems are developed.

Originality/value

Compared with most existing literature, the proposed distributed tracking algorithms use fuzzy control and adaptive control techniques to cope with system nonlinear uncertainties of multiple mechanical systems. Moreover, the improved control strategy not only reduces fuzzy rules but also has higher control accuracy.

Details

Assembly Automation, vol. 39 no. 1
Type: Research Article
ISSN: 0144-5154

Keywords

Article
Publication date: 7 August 2019

Zhengyu Huang, Lingyu Chen, Lianchao Zhang, Shixun Fan and Dapeng Fan

This paper aims to analyze the key factors influencing the synchronization performance of distributed motion control system and to improve the synchronization performance for…

Abstract

Purpose

This paper aims to analyze the key factors influencing the synchronization performance of distributed motion control system and to improve the synchronization performance for peripherals control of this system.

Design/methodology/approach

This paper deals with the software synchronization problems of distributed motion control system based on real-time Ethernet. First, combined with communication and control tasks, the key factors affecting synchronization performance of system are analyzed. Then, aiming at key factors and considering the synchronization of system bus, protocol conversion and task scheduling, a software synchronization method based on CANopen protocol and real-time Ethernet is proposed. Finally, the feasibility of this method is verified by establishing distributed motion control system and testing the synchronization performance of terminal control signals of slaves.

Findings

Based on this method, the results show that the synchronization accuracy for peripherals control of all slaves could be about 100 ns.

Practical implications

This research provides high-precision synchronization method, which could lay a foundation for the application of distributed motion control system in the field of assembly automation, such as multi-axis assembly robots control.

Originality/value

In distributed motion control system, many factors affect the synchronization performance. At present, there is no synchronization method that could comprehensively consider these factors. This paper not only analyzes the key factors influencing the synchronization performance of system but also proposes a synchronization method. Therefore, the method proposed in this paper has certain theoretical value and engineering significance.

Details

Assembly Automation, vol. 39 no. 5
Type: Research Article
ISSN: 0144-5154

Keywords

Article
Publication date: 1 June 1976

B.M. Doouss and G.L. Collins

This monograph defines distributed intelligence and discusses the relationship of distributed intelligence to data base, justifications for using the technique, and the approach…

67

Abstract

This monograph defines distributed intelligence and discusses the relationship of distributed intelligence to data base, justifications for using the technique, and the approach to successful implementation of the technique. The approach is then illustrated by reference to a case study of experience in Birds Eye Foods. The planning process by which computing strategy for the company was decided is described, and the planning conclusions reached to date are given. The current state of development in the company is outlined and the very real savings so far achieved are specified. Finally, the main conclusions of the monograph are brought together. In essence these conclusions are that major savings are achievable using distributed intelligence, and that the implementation of a company data processing plan can be made quicker and simpler by its use. However, careful central control must be maintained so as to avoid fragmentation of machine, language skills, and application taking place.

Details

Management Decision, vol. 14 no. 6
Type: Research Article
ISSN: 0025-1747

Article
Publication date: 4 June 2024

Subhi Jleilaty, Anas Ammounah, Ghiath Abdulmalek, Lydie Nouveliere, Hang Su and Samer Alfayad

This paper aims to develop an adaptable control architecture for electrohydraulic humanoid robots (HYDROïD) that emulate the functionality of the human nervous system. The…

Abstract

Purpose

This paper aims to develop an adaptable control architecture for electrohydraulic humanoid robots (HYDROïD) that emulate the functionality of the human nervous system. The developed control architecture overcomes the limitations of classical centralized and decentralized systems by distributing intelligence across controllers.

Design/methodology/approach

The proposed solution is a distributed real-time control architecture with robot operating system (ROS). The joint controllers have the intelligence to make decisions, dominate their actuators and publish their state. The real-time capabilities are ensured in the master controller by using a Preempt-RT kernel beside open robot control software middleware to operate the real-time tasks and in the customized joint controllers by free real-time operating systems firmware. Systems can be either centralized, where all components are connected to a central unit or decentralized, where distributed units act as interfaces between the I/Os and the master controller when the master controller is without the ability to make decisions.

Findings

The proposed architecture establishes a versatile and adaptive control framework. It features a centralized hardware topology with a master PC and distributed joint controllers, while the software architecture adapts based on the task. It operates in a distributed manner for precise, force-independent motions and in a decentralized manner for tasks requiring compliance and force control. This design enables the examination of the sensorimotor loop at both low-level joint controllers and the high-level master controller.

Originality/value

It developed a control architecture emulating the functionality of the human nervous system. The experimental validations were performed on the HYDROïD. The results demonstrated 50% advancements in the update rate compared to other humanoids and 30% in the latency of the master processor and the control tasks.

Details

Robotic Intelligence and Automation, vol. 44 no. 4
Type: Research Article
ISSN: 2754-6969

Keywords

Article
Publication date: 1 August 1997

N.P. Mahalik and P.R. Moore

During recent years, in the field of real‐time instrumentation and process control, there has been a trend away from centralized control system. Distributed control by using…

Abstract

During recent years, in the field of real‐time instrumentation and process control, there has been a trend away from centralized control system. Distributed control by using fieldbus technology is only the first step to application of intelligence in the field devices. Compares centralized systems with the distributed systems, differentiates the conventional LANs from the fieldbus technology and reviews the related technology and the current status of the international fieldbus standards. Describes some of the standard fieldbuses. Highlights the advantages of using fieldbuses in the real‐time process control and discusses what are the points to be considered before selecting a fieldbus. Highlights fieldbus‐based design development methodology involved in order to build a real‐time industrial distributed control system (RIDCS). Presents a case study with the LonWorks Technology; a fieldbus category system.

Details

Integrated Manufacturing Systems, vol. 8 no. 4
Type: Research Article
ISSN: 0957-6061

Keywords

Article
Publication date: 26 January 2010

Lixuan Lu and Jianhe Lei

Proper function of landing gear plays a crucial role in the safe operation of an airplane. Traditional landing gear control system utilizes centralized control technology. The…

1099

Abstract

Purpose

Proper function of landing gear plays a crucial role in the safe operation of an airplane. Traditional landing gear control system utilizes centralized control technology. The relatively heavy wire harness and low reliability accompanied with this technology make it logical to transfer from traditional control to real‐time distributed control. This paper aims to look into a new landing gear control system based on time‐triggered architecture (TTA).

Design/methodology/approach

In this paper, a new landing gear control system based on TTA is proposed. The reliability of the proposed system is investigated using a combination of Markov analysis and MIL‐HDBK‐217 methods.

Findings

The results show that by integration of TTP/C and TTP/A technologies, the advantages of both are achieved. A very high level of reliability is obtained. This increases the confidence when adopting distributed landing gear control technology.

Originality/value

The paper presents a new landing gear control system based on TTA, the reliability of which is very high.

Details

Aircraft Engineering and Aerospace Technology, vol. 82 no. 1
Type: Research Article
ISSN: 0002-2667

Keywords

Article
Publication date: 5 September 2016

S. Vahid Naghavi, A.A. Safavi, Mohammad Hassan Khooban, S. Pourdehi and Valiollah Ghaffari

The purpose of this paper is to concern the design of a robust model predictive controller for distributed networked systems with transmission delays.

Abstract

Purpose

The purpose of this paper is to concern the design of a robust model predictive controller for distributed networked systems with transmission delays.

Design/methodology/approach

The overall system is composed of a number of interconnected nonlinear subsystems with time-varying transmission delays. A distributed networked system with transmission delays is modeled as a nonlinear system with a time-varying delay. Time delays appear in distributed systems due to the information transmission in the communication network or transport of material between the sub-plants. In real applications, the states may not be available directly and it could be a challenge to address the control problem in interconnected systems using a centralized architecture because of the constraints on the computational capabilities and the communication bandwidth. The controller design is characterized as an optimization problem of a “worst-case” objective function over an infinite moving horizon.

Findings

The aim is to propose control synthesis approach that depends on nonlinearity and time varying delay characteristics. The MPC problem is represented in a time varying delayed state feedback structure. Then the synthesis sufficient condition is provided in the form of a linear matrix inequality (LMI) optimization and is solved online at each time instant. In the rest, an LMI-based decentralized observer-based robust model predictive control strategy is proposed.

Originality/value

The authors develop RMPC strategies for a class of distributed networked systems with transmission delays using LMI-Based technique. To evaluate the applicability of the developed approach, the control design of a networked chemical reactor plant with two sub-plants is studied. The simulation results show the effectiveness of the proposed method.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 35 no. 5
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 1 February 2016

Yang Meng and Zi Wang

This paper aims to study that for multi-agent systems, how to find proper control protocols to ensure synchronization when the input set of each agent is not the whole real axis…

Abstract

Purpose

This paper aims to study that for multi-agent systems, how to find proper control protocols to ensure synchronization when the input set of each agent is not the whole real axis but a discrete set, and how the coarseness of imprecise input sets affect the synchronization control of the multi-agent systems.

Design/methodology/approach

The paper uses a relative state feedback method and non-linear mapping functions to design a proper control protocol which matches the coarseness of the input set and ensures synchronization. For theoretical analysis, the paper uses an error analysis method and mathematic induction to prove the effectiveness of the designed control protocol. The paper also uses a numerical example to show the correctness of the theoretical results.

Findings

The paper provides a method for protocol design when the input set of each agent is imprecise. The paper establishes a bi-direction relationship which suffices for synchronization between the coarseness of the input set and the synchronization precision, and finds that this relationship describes how the coarseness of the input set affects the synchronization control of the multi-agent system.

Research limitations/implications

This paper only studies the case with logarithmically distributed and uniformly distributed discrete input sets. The authors are encouraged to study the synchronization control of multi-agent systems under input sets with more general distributions.

Practical implications

The paper includes implications for coordination control of multi-agent networks when the actuator of each agent is with a limited capacity, which leads to the case of discrete input sets with limit precision.

Originality/value

This paper fulfils an identified need to study how the coarseness of the input set of each agent affects the synchronization control of the whole multi-agent system.

Details

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

Keywords

Article
Publication date: 2 May 2017

Sergio Barile, Cristina Simone and Mario Calabrese

This paper aims to focus on distributed technologies with the aim of highlighting their economic-organizational dimensions. In particular, the contribution first presents a deeper…

Abstract

Purpose

This paper aims to focus on distributed technologies with the aim of highlighting their economic-organizational dimensions. In particular, the contribution first presents a deeper understanding of the nature and the dynamics of the economies and diseconomies that arise from the adoption and diffusion of distributed technologies. Second, it aims to shed light on the increasing tension between the hierarchy-based model of production and peer-to-peer (p2p) production, which involves the pervasive diffusion of distributed technologies.

Design/methodology/approach

Adopting an economic-organizational perspective, which is deeply rooted in the related extant literature, an analytically consistent model is developed to simultaneously take into account the following variables: adoption density independent variable) and economies of knowledge integration and organizational diseconomies (the costs of a loss of control and the costs of organizational decoupling and recoupling) as dependent variables.

Findings

Distributed technologies allow access to a large quantity and a wide variety of cognitive slacks that have not been possible until now. In doing so, they are leading the transition towards p2p. This is an emerging production paradigm that is characterized – with respect to mass production – by a shift in the relative importance of cognitive slack in comparison with tangible slack. Nevertheless, the unrestrainable diffusion of distributed technologies is not neutral for organizations. On the one hand, these technologies allow for the integration of economies of knowledge, and on the other hand, they involve organizational diseconomies that should not be ignored by managers and researchers.

Originality/value

This paper fills a gap in the literature by developing a consistent analytical framework that simultaneously takes into account the economies of knowledge integration and potential organizational diseconomies (the costs of coordination and the loss of control) that arise from the adoption and diffusion of distributed technologies.

Details

Kybernetes, vol. 46 no. 5
Type: Research Article
ISSN: 0368-492X

Keywords

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