IEEE Transactions on Industrial Electronics

Volume 49, Number 6, Dec 2002 Access to the journal on IEEE XPLORE IE Transactions Home Page

Special Sections on Factory Communication System

49.6.1	R. Zurawski, "Guest editorial," IEEE Trans. on Industrial Electronics, vol. 49, no. 6, pp. 1186- 1188, Dec 2002. Abstract Link Full Text Abstract: Not Available
49.6.2	L. Almeida, P. Pedreiras, J.A.G. Fonseca, "The FTT-CAN protocol: why and how," IEEE Trans. on Industrial Electronics, vol. 49, no. 6, pp. 1189- 1201, Dec 2002. Abstract Link Full Text Abstract: The requirement for flexible operation is becoming increasingly important in modern industrial systems. This requirement has to be supported at all system levels, including the field level in process industry, as well as the cell and machine control levels in manufacturing industry, where fieldbus-based communication systems are commonly found. Furthermore, typical applications at these levels require both time- and event-triggered communication services, in most cases under stringent timing constraints, to convey state data in the former case and alarms and management data in the latter. However, neither the requirement for flexible operation under guaranteed timeliness nor for joint support of time and event-triggered traffic are efficiently fulfilled by most of existing fieldbus systems. This paper presents a new protocol, flexible time-triggered communication on controller area network, which fulfills both requirements: it supports time-triggered communication in a flexible way as well as being an efficient combination of both time- and event-triggered traffic with temporal isolation. These types of traffic are handled by two complementary subsystems, the synchronous and the asynchronous messaging systems, respectively. The paper includes a justification for the new protocol as well as its description and worst case temporal analysis for both subsystems. This analysis shows the capability of the protocol to convey real-time traffic of either type.
49.6.3	G. Cena, A. Valenzano, "Achieving round-robin access in controller area networks," IEEE Trans. on Industrial Electronics, vol. 49, no. 6, pp. 1202- 1213, Dec 2002. Abstract Link Full Text Abstract: Because of their low implementation costs, optimum responsiveness, and widespread availability, controller area networks (CANS) are being used more and more today to support communications in real-time systems. However, under heavy traffic conditions the CAN access protocol may exhibit a quite unfair behavior, in particular, when the control applications require the same quality of service to be ensured to a number of different objects. In this paper, a new technique is proposed which is based on CAN and introduces few changes to the original protocol. Such a solution is able to ensure a very fair behavior-which resembles the one obtained in token-based networks-while maintaining, at the same time, the reduced access delays typical of CAN when operating in low traffic conditions. Furthermore, it preserves an optimum degree of compatibility with the existing devices and applications based on CAN.
49.6.4	M. Conti, L. Donatiello, M. Furini, "Design and analysis of RT-Ring: a protocol for supporting real-time communications," IEEE Trans. on Industrial Electronics, vol. 49, no. 6, pp. 1214- 1226, Dec 2002. Abstract Link Full Text Abstract: Distributed applications with quality of service (QoS) requirements are more and more used in several areas (e.g., automated factory networks, embedded systems, conferencing systems). These applications produce a type of traffic with hard timing requirements, i.e., transmissions must be completed within specified deadlines. To handle these transmissions, the communication system must use real-time protocols to provide a communication service that is able to satisfy the QoS requirements of the distributed applications. In this paper, the authors propose a new real-time protocol, called RT-Ring, able to support transmissions of both real-time and generic traffic over a ring network. RT-Ring provides both network guarantees and high network resource utilization, while ensuring the compatibility with the emerging differentiated service architectures. Network guarantees are fully proved and high network utilization is highlighted by a comparative study with the FDDI protocol. This comparison shows that RT-Ring network capacities are greater than the corresponding FDDI capacities. In fact, by assuming the FDDI frames with a length equal to the RT-Ring slot size and by using the same traffic load the authors show that the capacities of FDDI are equal to the lower bound capacities of RT-Ring.
49.6.5	G. Cena, A. Valenzano, "A multistage hierarchical distributed arbitration technique for priority-based real-time communication systems," IEEE Trans. on Industrial Electronics, vol. 49, no. 6, pp. 1227- 1239, Dec 2002. Abstract Link Full Text Abstract: ISO 11898 is a communication protocol based on the carrier sense multiple access with collision detection and arbitration on message priority (CSMA/CD+AMP) technique, which at present is largely used as a real-time network for industrial environments. Unfortunately, because of the peculiarities of the arbitration technique it adopts, it suffers from severe limitations on the maximum extension of the network, which cannot be overcome simply by means of improvements in the transceiver's technology as they depend on the limited propagation speed of the signals on the communication support. In this paper, a new kind of network is presented that features a behavior very similar to ISO 11898, but which achieves noticeably larger areas to be covered without having to reduce the bit rate. It relies on a tree topology and adopts a brand new multistage hierarchical distributed arbitration technique, which takes the increased propagation delays into account properly.
49.6.6	H.A. Hansson, T. Nolte, C. Norstrom, S. Punnekkat, "Integrating reliability and timing analysis of CAN-based systems," IEEE Trans. on Industrial Electronics, vol. 49, no. 6, pp. 1240- 1250, Dec 2002. Abstract Link Full Text Abstract: This paper presents and illustrates a reliability analysis method developed with a focus on controller-area-network-based automotive systems. The method considers the effect of faults on schedulability analysis and its impact on the reliability estimation of the system, and attempts to integrate both to aid system developers. The authors illustrate the method by modeling a simple distributed antilock braking system, and showing that even in cases where the worst case analysis deems the system unschedulable, it may be proven to satisfy its timing requirements with a sufficiently high probability. From a reliability and cost perspective, this paper underlines the tradeoffs between timing guarantees, the level of hardware and software faults, and per-unit cost.
49.6.7	P. Castelpietra, Ye-Qiong Song, F. Simonot-Lion, M. Attia, "Analysis and simulation methods for performance evaluation of a multiple networked embedded architecture," IEEE Trans. on Industrial Electronics, vol. 49, no. 6, pp. 1251- 1264, Dec 2002. Abstract Link Full Text Abstract: This paper deals with the modeling and the validation of multiple networked embedded computer systems supporting in-vehicle applications. In this context, the authors developed a modular modeling and simulation technique. This approach allowed the development of reusable component models with clearly defined interfaces. The building of a whole application model is then obtained by the integration of these components, so that model construction and result analysis are made easy. In fact, thanks to the formal definition of components, interfaces, and composition rules, this step is automatically achieved. In the context of the CAROSSE project, we implemented this methodology in the Carosse-Perf tool. Herein, the authors detail the methodology together with its modeling principles and the resulting definition of basic components and interfaces. Finally, they apply it to a case study drawn from a PSA Peugeot-Citroen application.
49.6.8	A. Willig, M. Kubisch, C. Hoene, A. Wolisz, "Measurements of a wireless link in an industrial environment using an IEEE 802.11-compliant physical layer," IEEE Trans. on Industrial Electronics, vol. 49, no. 6, pp. 1265- 1282, Dec 2002. Abstract Link Full Text Abstract: The design and simulation of coding schemes, medium access control (MAC), and link-layer protocols for future industrial wireless local area networks can be supported by some understanding of the statistical properties of the bit error patterns delivered by a wireless link (which is an ensemble of transmitter, channel, receiver, modems). The authors present results of bit error measurements taken with an IEEE 802.11-compliant radio modem in an industrial environment. In addition to reporting the most important results, they draw some conclusions for the design of MAC and link-layer protocols. Furthermore, they show that the popular Gilbert/Elliot model and a modified version of it are a useful tool for simulating bit errors on a wireless link, despite their simplicity and failure to match certain measured statistics.
49.6.9	S. Senini, P.J. Wolfs, "Analysis and design of a multiple-loop control system for a hybrid active filter," IEEE Trans. on Industrial Electronics, vol. 49, no. 6, pp. 1283- 1292, Dec 2002. Abstract Link Full Text Abstract: This paper investigates the control of a hybrid active filter consisting of a single tuned resonant branch and an active element. This filter is capable of suppressing multiple harmonics using a multiple-loop control system. Linear continuous-time models are first developed in the dq reference frame. This results in a two-input/two-output system with cross coupling. The continuous model is discretized and the design of a multiple-loop discrete-time controller is examined. Wideband current feedback loops are shown to affect the coupling between the d- and q-axis controllers and provide a resistance-like damping effect. Variations in stability with processing delay times are examined. Finally, this work is extended to include narrowband harmonic specific controls. The results of the control study are confirmed by simulation and experimental results. Power Electronics
49.6.10	J. Hamar, I. Nagy, "Control features of dual-channel DC-DC converters," IEEE Trans. on Industrial Electronics, vol. 49, no. 6, pp. 1293- 1305, Dec 2002. Abstract Link Full Text Abstract: This paper presents the steady-state behavior of a two-channel resonant converter family in symmetrical operation. Six configurations will be investigated, including step-down, step-up/down, and step-up ones in continuous conduction mode (CCM) and in discontinuous conduction mode (DCM). Exploring the conditions of transition from CCM to DCM or back, it becomes evident that the CCM operation is definitely restricted, that is, sometimes the converter cannot he operated in CCM at all. The most important relations among the input, output, and control variables are derived and verified by simulation and experimental results. Emerging Technology
49.6.11	N.M. Botros, Jian Yang, P. Feinsilver, R. Schott, "Hardware realization of Krawtchouk transform using VHDL modeling and FPGAs," IEEE Trans. on Industrial Electronics, vol. 49, no. 6, pp. 1306- 1312, Dec 2002. Abstract Link Full Text Abstract: In this paper, the authors present a hardware realization of a simplified Krawtchouk transform. The transform is realized on a Xilinx field-programmable gate arrays chip. The hardware is stand-alone and operates on a real-time basis. Very high speed integrated circuit hardware descriptive language structural, behavioral, and data flow modeling are implemented to describe, simulate, and realize the transform. The hardware consists mainly of an 8 /spl times/ 8-2's-complement multiplier, a 16-b accumulator, a 16 /spl times/ 16-b RAM, a 64 /spl times/ 8-b ROM, and a microprogram-based control unit. A brief analysis of the transform and a contrast between its hardware and that of Fourier transform are presented. The hardware is tested by inputting an eight-point data vector to the input pins of the chip. The results of the transform are read from the output pins of the chip. The results are compared with those obtained from a software program executing the same transform for the same input data vector as the hardware. It is found that results from the hardware match those of the software. Robotics and Vision
49.6.12	Kao-Shing Hwang, Ming-Yi Ju, "A propagating interface model strategy for global trajectory planning among moving obstacles," IEEE Trans. on Industrial Electronics, vol. 49, no. 6, pp. 1313- 1322, Dec 2002. Abstract Link Full Text Abstract: A global trajectory planning method which employs a collision-trend index and a propagating interface model to perform mobile robot navigation is presented in this paper. To simplify the mathematical representation and geometrical approximation, all the objects in the workspace are modeled as ellipses. Using a series of geometrical transformations between the ellipses, which represent the mobile robot and obstacles, the computational complexity of collision detection in trajectory planning can be reduced tremendously. To keep the front propagating in the normal direction with positive propagating speed, the collision-trend index plays an important role in determining the propagating speed for a front over workspace. The index is obtained by mapping the geometrical relationship between the ellipses into the profile of a Gaussian distribution. Several simulations to demonstrate the performance of the proposed method are given. The results reveal that the proposed method is always able to generate an optimal collision-free trajectory for a mobile robot navigating in an environment with dynamic and static obstacles. Letters to the Editor
49.6.13	Rong-Jong Wai, "Development of new training algorithms for neuro-wavelet systems on the robust control of induction servo motor drive," IEEE Trans. on Industrial Electronics, vol. 49, no. 6, pp. 1323- 1341, Dec 2002. Abstract Link Full Text Abstract: A robust wavelet neural network control (RWNNC) system is proposed to control the rotor position of an induction servo motor drive in this paper. In the proposed RWNNC system, a wavelet neural network controller is the main tracking controller that is used to mimic a computed torque control law, and a robust controller is designed to recover the residual approximation for ensuring the stable control performance. Moreover, to relax the requirement for a known bound on lumped uncertainty, which comprises a minimum approximation error, optimal network parameters and higher order terms in a Taylor series expansion of the wavelet functions, an RWNNC system with adaptive bound estimation was investigated for the control of an induction servo motor drive. In this control system, a simple adaptive algorithm was utilized to estimate the bound on lumped uncertainty. In addition, numerical simulation and experimental results due to periodic commands show that the dynamic behaviors of the proposed control systems are robust with regard to parameter variations and external load disturbance.
49.6.14	C.C. Chan, Zheng Ming Zhao, C. Qian, S. Meng, "Comparisons of PWM and one-cycle control for power amplifier with multilevel converter," IEEE Trans. on Industrial Electronics, vol. 49, no. 6, pp. 1342- 1344, Dec 2002. Abstract Link Full Text Abstract: Based on the concepts of cascade multilevel converters and one-cycle technique, comparisons are conducted to characterize the distortion of the pulsewidth modulation (PWM) and one-cycle control methods that were applied to converters. Simulation results for the different control schemes are obtained in PSIM software initially to see the effect of one-cycle control different from that of PWM control. Through the comparisons, the advantages and disadvantages are identified for each method. The one-cycle scheme is better than PWM control in reducing undesirable harmonics and tracing dynamic waveforms. Simulation and experimental results are also provided to verify the conclusions.
49.6.15	C. Mademlis, N. Margaris, "Loss minimization in vector-controlled interior permanent-magnet synchronous motor drives," IEEE Trans. on Industrial Electronics, vol. 49, no. 6, pp. 1344- 1347, Dec 2002. Abstract Link Full Text Abstract: An efficiency optimization method for vector-controlled interior permanent-magnet synchronous motor drives is presented. Based on theoretical analysis, a loss minimization condition that determines the optimal d-axis component of the armature current is derived. Selected experimental results are presented to validate the effectiveness of the proposed control method.
49.6.16	"Author Index," IEEE Trans. on Industrial Electronics, vol. 49, no. 6, pp. 1348- 1353, Dec 2002. Abstract Link Full Text Abstract: Not Available
49.6.17	"Subject Index," IEEE Trans. on Industrial Electronics, vol. 49, no. 6, pp. 1353- 1371, Dec 2002. Abstract Link Full Text Abstract: Not Available