As the popularization of dual ring fieldbus, the optimized dual ring synchronization methods are still in short. The current synchronization methods are generally established in traditional industrial fieldbus, in whi...As the popularization of dual ring fieldbus, the optimized dual ring synchronization methods are still in short. The current synchronization methods are generally established in traditional industrial fieldbus, in which transmission is commonly considered in single track, the two-way transmitting cannot take full effect, and would result in unwanted idle load on equipment lines. In stamp-transferring part, the synchronizing algorithm is not properly processed to diminish the latency, so the real-time performance of entire system cannot be ensured. To support the synchronization control of stations in the CNC system, a real-time time synchronization method for dual ring fieldbus in the CNC system is designed in this paper. In this method a synchronizing message transmission scheme based on dual ring architecture and the synchronization algorithm between master and secondary stations are integrated. In the scheme, the clock models of both master and secondary stations are optimized with corresponding modules and the stamp data transmission based on the dual ring fieldbus is devised exclusively, so the transmitting efficiency improves with less idle work. In the algorithm, all the secondary stations can accomplish the consistent state with master station by updating clock discrepancy information in one communication cycle, and it takes the advantage of two-way transmitting and makes the best use of dual ring structure, so the real-time performance of the system can be promoted while retaining the precision of synchronization. To evaluate the performance, the costs of the method and errors during synchronizing are noted and analyzed based on the actual running environment in the industrial fieldbus. The results show that it reduces communication cost and ensures the smoothness of the system with low lag effects under heavy load. The proposed time synchronization method optimizes the architecture of sync message transmission in dual ring fieldbus, and improves the efficiency of time synchronization in the stations of CNC system.展开更多
Fieldbus and industrial Ethernet standards can guide the specification andcoordinate bus optimization. The standards are the basis for the development of field-bus and industrial Ethernet. In this paper, we review com...Fieldbus and industrial Ethernet standards can guide the specification andcoordinate bus optimization. The standards are the basis for the development of field-bus and industrial Ethernet. In this paper, we review complex standard systems allover the world. We discuss 18 fieldbus standards, including the International Electro-technical Commission(IEC) 61158, the IEC 61784 standard matched with IEC 61158,the controller and device interface standard IEC 62026 for low voltage distributionand control devices, and the International Organization for Standardization(ISO)11898 and ISO 11519 standards related to the controller area network(CAN) bus. Wealso introduce the standards of China, Europe, Japan and America. This paper pro-vides a reference to develop fieldbus and industrial Ethernet products for Chinese en-terprises.展开更多
The wireless fieldbus is a vital part in present industrial automatic controls and software-defined systems. Accompanying, security is an upcoming problem determines its future leapfrog development. Wireless fieldbus ...The wireless fieldbus is a vital part in present industrial automatic controls and software-defined systems. Accompanying, security is an upcoming problem determines its future leapfrog development. Wireless fieldbus systems can be made secure by encrypting the data. Unfortunately, the diffusion character of encryption brings significant vulnerabilities in terms of deteriorated error performance and energy efficiency. In this paper, we first propose an AES-dependent Hsiao(AD-Hsiao) code to improve the error correction capability, which leverages the prior information of data similarity and AES decryption to assist syndrome decoding. Then, we develop "Random Coset" scheme to reduce energy consumption. Based on mapping written data into several data candidates, this scheme lessens the number of bits written to memory and thereby boosts the write energy efficiency. Simulation results show that the AD-Hsiao code can correct majority of double errors in a single codeword with limited latency and area cost as the Hamming code. Moreover, the(72,64) AD-Hsiao code improves the reliability by 102 over the(72,64) Hamming code at 8 dB AWGN channel, and also exceeding the high cost(78,64) BCH code. In addition, the "Random Coset" improves energy efficiency by 6.6~14% than the current scheme while re-quires small ROM storage.展开更多
Technical features about CAN bus are described. One kind of scheme in Hotel Guest Room Service and Management System based on CAN bus is presented. The system's structure and main function are expounded. The work ...Technical features about CAN bus are described. One kind of scheme in Hotel Guest Room Service and Management System based on CAN bus is presented. The system's structure and main function are expounded. The work principle and design of the system's hardware and software are explained. The realization of the system's hardware and software is detailed from aspects of improving system's anti-jamming and fault self-examined capability, and the block diagram of each part's circuit is given. Finally, features of the system are summarized, and a comparison with the system based on RS485 was made to prove the advantages of the system. By practice, CAN bus in the system can transmit data steadily and reliably.展开更多
基金supported by National Projects for Science and Technology Development of China(Grant No.2011ZX04016-071)National Basic Research Program of China(973 Program,Grant No.2011CB302400-G,the mathematical mechanization method and its application in digital design and manufacturing)
文摘As the popularization of dual ring fieldbus, the optimized dual ring synchronization methods are still in short. The current synchronization methods are generally established in traditional industrial fieldbus, in which transmission is commonly considered in single track, the two-way transmitting cannot take full effect, and would result in unwanted idle load on equipment lines. In stamp-transferring part, the synchronizing algorithm is not properly processed to diminish the latency, so the real-time performance of entire system cannot be ensured. To support the synchronization control of stations in the CNC system, a real-time time synchronization method for dual ring fieldbus in the CNC system is designed in this paper. In this method a synchronizing message transmission scheme based on dual ring architecture and the synchronization algorithm between master and secondary stations are integrated. In the scheme, the clock models of both master and secondary stations are optimized with corresponding modules and the stamp data transmission based on the dual ring fieldbus is devised exclusively, so the transmitting efficiency improves with less idle work. In the algorithm, all the secondary stations can accomplish the consistent state with master station by updating clock discrepancy information in one communication cycle, and it takes the advantage of two-way transmitting and makes the best use of dual ring structure, so the real-time performance of the system can be promoted while retaining the precision of synchronization. To evaluate the performance, the costs of the method and errors during synchronizing are noted and analyzed based on the actual running environment in the industrial fieldbus. The results show that it reduces communication cost and ensures the smoothness of the system with low lag effects under heavy load. The proposed time synchronization method optimizes the architecture of sync message transmission in dual ring fieldbus, and improves the efficiency of time synchronization in the stations of CNC system.
基金supported by ZTE Industry-Academia-Research Cooperation Funds under Grant No.2016ZTE04-08
文摘Fieldbus and industrial Ethernet standards can guide the specification andcoordinate bus optimization. The standards are the basis for the development of field-bus and industrial Ethernet. In this paper, we review complex standard systems allover the world. We discuss 18 fieldbus standards, including the International Electro-technical Commission(IEC) 61158, the IEC 61784 standard matched with IEC 61158,the controller and device interface standard IEC 62026 for low voltage distributionand control devices, and the International Organization for Standardization(ISO)11898 and ISO 11519 standards related to the controller area network(CAN) bus. Wealso introduce the standards of China, Europe, Japan and America. This paper pro-vides a reference to develop fieldbus and industrial Ethernet products for Chinese en-terprises.
基金supported by the National Natural Science Foundation of China (NSFC, 91538202, 91338103)the new strategic industries development projects of Shenzhen City (JCYJ20160520140157342,CXZZ20150928165834560)
文摘The wireless fieldbus is a vital part in present industrial automatic controls and software-defined systems. Accompanying, security is an upcoming problem determines its future leapfrog development. Wireless fieldbus systems can be made secure by encrypting the data. Unfortunately, the diffusion character of encryption brings significant vulnerabilities in terms of deteriorated error performance and energy efficiency. In this paper, we first propose an AES-dependent Hsiao(AD-Hsiao) code to improve the error correction capability, which leverages the prior information of data similarity and AES decryption to assist syndrome decoding. Then, we develop "Random Coset" scheme to reduce energy consumption. Based on mapping written data into several data candidates, this scheme lessens the number of bits written to memory and thereby boosts the write energy efficiency. Simulation results show that the AD-Hsiao code can correct majority of double errors in a single codeword with limited latency and area cost as the Hamming code. Moreover, the(72,64) AD-Hsiao code improves the reliability by 102 over the(72,64) Hamming code at 8 dB AWGN channel, and also exceeding the high cost(78,64) BCH code. In addition, the "Random Coset" improves energy efficiency by 6.6~14% than the current scheme while re-quires small ROM storage.
文摘Technical features about CAN bus are described. One kind of scheme in Hotel Guest Room Service and Management System based on CAN bus is presented. The system's structure and main function are expounded. The work principle and design of the system's hardware and software are explained. The realization of the system's hardware and software is detailed from aspects of improving system's anti-jamming and fault self-examined capability, and the block diagram of each part's circuit is given. Finally, features of the system are summarized, and a comparison with the system based on RS485 was made to prove the advantages of the system. By practice, CAN bus in the system can transmit data steadily and reliably.