• Journal of Power System Engineering
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• v.13 no.2
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• pp.71-82
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• 2009

This paper presents a real-time haptic rendering method for a realistic force feedback in a remote environment with varying communication time-delay. The remote environment is assumed as a virtual environment based on a computer graphics, for example, on-line shopping mall, internet game and cyber-education. The properties of a virtual object such as stiffness and viscosity are assumed to be unknown because they are changed according to the contact position and/or a penetrated depth into the object. The DARMAX model based output estimator is proposed to trace the correct impedance of the virtual object in real-time. The output estimator is developed on the input-output relationship. It can trace the varying impedance in real-time by virtue of P-matrix resetting algorithm. And the estimator can trace the correct impedance by using a white noise that prevents the biased input-output information. Realistic output forces are generated in real-time, by using the inputs and the estimated impedance, even though the communication time delay and the impedance of the virtual object are unknown and changed. The generated forces trace the analytical forces computed from the virtual model of the remote environment. Performance is demonstrated by experiments with a 1-dof haptic device and a spring-damper-based virtual model.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.34-34
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• 2000

One of the basic goals, when considering networks for communication in industrial control applications, is the reduction of complexity of related wiring harnesses. In addition, the networking offers the advantages for industrial control applications, such as ease of cabling, ease of changes in the cabling, ease of adding controller modules, etc. CAN (Controller Area Network) is generally applied in car networking in order to reduce the complexity of the related wiring harnesses. These traditional CAN application techniques are modified to achieve the real time communication for the industrial control applications. In this paper, we propose the method of CAN Identifier assignment for Real-Time network system. This method is can be used to scheduling messages on CAN for Real-Time network system. And also, the real-time network system is developed and the proposed moth(Ids are verified experimentally.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.9 no.3
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• pp.244-248
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• 2009

This paper describes a real-time EtherCAT Master library. The library is developed using Xenomai. Xenomai is a real-time development framework. It cooperates with the Linux kernel, in order to provide a pervasive, interface-agnostic, hard real-time support to user-space applications, seamlessly integrated into the GNU/Linux environment. The proposed master library implements EtherCAT protocol for master side, and supports Application Programming Interfaces(APIs) for programming of real-time application which controls EtherCAT slave.

• Proceedings of the Acoustical Society of Korea Conference
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• 1998.06c
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• pp.351.1-355
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• 1998

Network-based real-time multimedia applications require guaranteed performances of communication service. Also according to increased bandwidth and processing performance in the future high speed networks, it is possible to make multimedia real-time applications such as distributed real-time applications including video conference, medical imaging, and video education. These applications have characteristics of stringent performance requirements in terms of delay, delay jitter and maximum loss rate. This paper proposes a new delay control for Broadband networks with FCFS queueing. The delay control provides an alternative solution to a current problem in real-time communication; traffic distortion, which makes it difficult to meet such real-time requirements. In simulations, it shows that the proposed delay control can guarantee local and end-to-end delay.

• Journal of information and communication convergence engineering
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• v.10 no.4
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• pp.372-377
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• 2012

In this paper, we propose an implementation of a real-time operating system for the two-wheel mobile robot. With this implementation, we have the ability to control the complex embedded systems of the two-wheel mobile robot. The advantage of the real-time operating system is increasing the reliability and stability of the two-wheel mobile robot when they work in critical environments such as military and industrial applications. The real-time operating system which was ported to this implementation is open systems and the corresponding interfaces for automotive electronics (OSEK/VDX). It is known as the set of specifications on automotive operating systems, published by a consortium founded by the automotive industry. The mechanical design and kinematics of the two-wheel mobile robot are described in this paper. The contributions of this paper suggest a method for adapting and porting OSEK/VDX real-time operating system to the two-wheel mobile robot with the differential drive method, and we are also able to apply the real-time operating system to any complex embedded system easily.

• International Journal of Internet, Broadcasting and Communication
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• v.14 no.1
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• pp.129-135
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• 2022

Real human digital models appear more and more frequently in VR/AR application scenarios, in which real-time markerless face capture animation of personalized virtual human faces is an important research topic. The traditional way to achieve personalized real human facial animation requires multiple mature animation staff, and in practice, the complex process and difficult technology may bring obstacles to inexperienced users. This paper proposes a new process to solve this kind of work, which has the advantages of low cost and less time than the traditional production method. For the personalized real human face model obtained by 3D reconstruction technology, first, use R3ds Wrap to topology the model, then use Avatary to make 52 Blend-Shape model files suitable for AR-Kit, and finally realize real-time markerless face capture 3D real human on the UE4 platform facial motion capture, this study makes rational use of the advantages of software and proposes a more efficient workflow for real-time markerless facial motion capture of personalized 3D real human models, The process ideas proposed in this paper can be helpful for other scholars who study this kind of work.

• Journal of Institute of Control, Robotics and Systems
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• v.6 no.7
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• pp.602-610
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• 2000

In communication networks used in safety-critical systems such as control systems in nuclear power plants there exist three types of data traffic : urgent or asynchronous hard real-time data hard real-time periodic data and soft real-time periodic data. it is necessary to allocate a suitable bandwidth to each data traffic in order to meet their real-time constraints. This paper proposes a method to meet the real-time constraints for the three types of data traffic simultaneously under a timer-controlled token bus protocol or the IEEE 802.4 token bus protocol and verifies the validity of the presented method by an example. This paper derives the proper region of the high priority token hold time and the target token rotation time for each station within which the real-time constraints for the three types of data traffic are met, Since the scheduling of the data traffic may reduce the possibility of the abrupt increase of the network load this paper proposes a brief heuristic method to make a scheduling table to satisfy their real-time constraints.

• Journal of information and communication convergence engineering
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• v.8 no.2
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• pp.212-218
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• 2010

In wireless sensor networks (WSNs), both efficient energy management and Quality of Service (QoS) are important issues for some applications. For creating robust networks, real-time services are usually employed to satisfy the QoS requirements. In this paper, we proposed a hierarchical real-time MAC (medium access control) protocol for (m,k)-firm constraint in wireless sensor networks shortly called HRTS-MAC. The proposed HRTS-MAC protocol is based on a dynamic priority assignment by (m,k)-firm constraint. In a tree structure topology, the scheduling algorithm assigns uniform transmitting opportunities to each node. The paper also provides experimental results and comparison of the proposed protocol with E_DBP scheduling algorithm.

• ETRI Journal
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• v.21 no.4
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• pp.52-64
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• 1999

QoS monitoring is a kind of real-time systems which allows each level of the system to track the ongoing QoS levels achieved by the lower network layers. For these systems, real-time communications between corresponding transport protocol objects is essential for their correct behavior. When two or more entities are employed to perform a certain task as in the case of communication protocols, the capability to do so is called interoperability and considered as the essential aspect of correctness of communication systems. This paper describes a formal approach on modeling and interoperability test case generation of a real-time QoS monitoring protocol. For this, we specify the behavior of flow monitoring of transport layer QoS protocol, i.e., METS protocol, which is proposed to address QoS from an end-to-end's point of view, based on QoS architecture model which includes ATM net work in lower layers. We use a real-time Input/Output finite State Machine to model the behavior of real-time flow monitoring over time. From the modeled real-time I/OFSM, we generate interoperability test cases to check the correctness of METS protocol's flow monitoring behaviors for two end systems. A new approach to efficient interoperability testing is described and the method of interoperability test cases generation is shown with the example of METS protocol's flow monitoring. The current TTCN is not appropriate for testing real-time and multimedia systems. Because test events in TTCN are for message-based system and not for stream-based systems, the real-time in TTCN can only be approximated. This paper also proposes the notation of real-time Abstract Test Suite by means of real-time extension of TTCN. This approach gives the advantages that only a few syntactical changes are necessary, and TTCN and real-time TTCN are compatible. This formal approach on interoperability testing can be applied to the real-time protocols related to IMT-2000, B-ISDN and real-time systems.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.54 no.11
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• pp.660-668
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• 2005

Digital communication networks have become a core technology in advanced building automation systems. BACnet (Building Automation and Control networks) is a standard data communication protocol designed specifically for building automation and control systems. BACnet adopts Master-Slave/Token-Passing (MS/TP) protocol as one of its field level networks. Tn this study, we introduce a method of implementing bandwidth allocation scheme in the MS/TP protocol. The bandwidth allocation scheme improves the capability of real-time communication of the original MS/TP protocol. The bandwidth allocation scheme introduced in this paper can be easily implemented in the existing MS/TP protocol with a slight modification. In this study, we examined the validity of bandwidth allocation scheme using simulation models. The results from the simulation experiment show that the proposed scheme satisfies the requirements of real-time communication.