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Aiming at the problems of limited coverage and imperfect function caused by the inflexible communication mode of the existing mine broadcast system, a design scheme of mine broadcast system integrating Ethernet, CAN bus and analog audio transmission is researched and designed, and the system architecture, hardware and software design and core technology of the system are described. The hardware of the system is composed of broadcast terminal and broadcast intercom speaker. The broadcast terminal uses Ethernet communication to realize network IP telephone and complete long-distance communication; broadcast intercom speaker through the CAN bus, combined with analog audio to achieve two-way intercom and streaming media online playback, with CAN relay function, can be unlimited cascaded, can be deployed where the optical fiber can not cover. The whole set of broadcasting system can realize full coverage of underground voice in coal mines, with the advantages of easy installation and low hardware cost, and provide strong support for daily safe production scheduling and disaster prevention and avoidance in coal mines.

In response to the problems of current electromagnetic compatibility testing methods for elevator control cabinets, including low intelligence, cumbersome operation, and lack of elevator system status monitoring, this paper proposes an electromagnetic compatibility testing method for elevator control cabinets and designs a set of electromagnetic compatibility testing and control system for elevator control cabinets. The author constructed an "upper computer+ lower computer" control system architecture, developed an embedded controller based on ARM, designed application software for upper and lower computers of the automatic testing process and control system, implemented such functions as sensor signal acquisition and CAN bus communication for elevator control cabinets, and realized the real-time monitoring of electromagnetic compatibility testing of elevator control cabinets and elevator system status. Then, the author used this system to carry out the conducted immunity, voltage dip, voltage interruption, electrical fast transient pulse group and surge tests on elevator control cabinets, and conducted simulation tests on elevator control cabinets for sensor signal abnormalities, power supply failures, and communication anomalies. The results show that the electromagnetic compatibility testing and control system of the elevator control cabinet operates stably, with accurate data collection and simple operation, accurately and efficiently identifies various types of faults, meets the needs of elevator manufacturers and testing institutions for electromagnetic compatibility testing, and compared with previous testing methods, reduces testing manpower input by about 67%.

Copyright of Journal of Computer Engineering & Applications is the property of Beijing Journal of Computer Engineering & Applications Journal Co Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Railway Signalling & Communication Engineering is the property of Railway Signalling & Communication Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ordnance Industry Automation is the property of Editorial Board for Ordnance Industry Automation and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In the intelligent connected age, CAN bus transmission faces the urgent demand of light weighted security encryption.Based on this, a fast response and high security CAN bus data encryption method was proposed.Since the 64 bit CAN packets were sent periodically, an online-offline block encryption algorithm coupled with message transmission cycle was proposed.In offline phase, the dynamic session key was generated by using advanced encryption standard.In online phase, the dynamic session key was used to quickly respond to encryption and decryption requests.The online computation delay was greatly reduced by the pre-encryption computation in offline phase, which helped achieving low latency and lightweight computation.At the same time, the ciphertext policy attribute based encryption was used to encrypt the block cipher.The access control policy made by the data sending OBU ensures that only the target OBU can decrypt the block cipher, so as to achieve targeted encryption.

Copyright of Computer Measurement & Control is the property of Magazine Agency of Computer Measurement & Control and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In the intelligent connected age, CAN bus transmission faces the urgent demand of light weighted security encryption. Based on this, a fast response and high security CAN bus data encryption method was proposed. Since the 64 bit CAN packets were sent periodically, an online-offline block encryption algorithm coupled with message transmission cycle was proposed. In offline phase, the dynamic session key was generated by using advanced encryption standard. In online phase, the dynamic session key was used to quickly respond to encryption and decryption requests. The online computation delay was greatly reduced by the pre-encryption computation in offline phase, which helped achieving low latency and lightweight computation. At the same time, the ciphertext policy attribute based encryption was used to encrypt the block cipher. The access control policy made by the data sending OBU ensures that only the target OBU can decrypt the block cipher, so as to achieve targeted encryption. [ABSTRACT FROM AUTHOR]

In view of the problems that the lack of portable CAN bus analysis equipment to quickly locate the CAN bus network fault nodes, interference elimination and reliability testing in the process of installation, debugging and daily maintenance of various CAN bus equipment in the coal mine, a portable mining CAN bus analyzer based on CAN bus analysis theory was researched and designed. The analyzer uses the main control chip STM32F429 as the core, and realizes the functions of CAN bus baud rate self-recognition, bus quality analysis and fault detection, message parsing, display and storage. The test results show that the analyzer can accurately analyze the communication quality of the bus and identify the bus faults which have important practical significance for the rapid troubleshooting of the bus faults and the improvement of the rationality and reliability of the bus network.

Copyright of Railway Signalling & Communication Engineering is the property of Railway Signalling & Communication Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Taking the gas drainage system as the platform and the industrial pointer instrument as the design object, this paper proposes and designs an automatic identification device for industrial instruments, which uses the camera to obtain the instrument image, obtains the instrument reading and local display through image recognition technology, and has CAN bus transmission. It solves the problems that a large number of industrial instruments in the gas drainage field need manual inspection, and do not have the data communication ability, and cannot communicate with the existing gas drainage system, and the purpose of accelerating the construction of intelligent mine has been achieved.

Copyright of Smart Rail Transit is the property of Smart Rail Transit Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In view of the difficulties in the field program upgrade of mine sensors in underground coal mines, a remote program update method based on CAN bus and IAP function is designed to get rid of the dependence of embedded software upgrade on the programmer. By designing the Flash programming method and program starting and guiding mode of STM32F103 microprocessor, the on-line upgrade of mine sensors in underground coal mine is realized. This paper introduces the overall implementation framework, upgrades program structure and process, and elaborates the IAP program update principle. The mine bus sensor program can be updated online by field application verification.

To deal with the complicated environmental conditions of the coal mine, in order to improve the flexibility, accuracy and timeliness of information interaction between coal mine safety monitoring system and equipment, in this paper, a monitoring sub-station based on CAN bus multi-master communication technology is designed. Firstly, the hardware circuit of the monitoring sub-station is designed as a whole, and then the communication protocol of CAN bus is optimized. The optimized protocol can realize multi-master communication of monitoring sub-station through reasonable design of address domain and address arrangement. Multi-master communication monitoring sub-station can effectively support bus multi-master communication, and the communication efficiency and flexibility of the system have been greatly improved.

CAN has become the most extensive fieldbus for contemporary automotive applications due to its outstanding reliability and flexibility.However,the standard CAN protocol does not provide sufficient security measures and is vulnerable to eavesdropping,replay,flooding,and denial of service attacks.In order to effectively detect whether the CAN bus is attacked,and to filter malicious messages when subjected to flooding attacks.The characteristics of vehicle CAN bus message communication were analyzed,and an intrusion detection method was proposed,which could effectively perform intrusion detection and malicious message filtering.Through experimental verification,the method can detect whether the CAN bus is attacked by 100%,and the accuracy of malicious packet filtering can reach over 99%.

CAN has become the most extensive fieldbus for contemporary automotive applications due to its outstanding reliability and flexibility. However, the standard CAN protocol does not provide sufficient security measures and is vulnerable to eavesdropping, replay, flooding, and denial of service attacks. In order to effectively detect whether the CAN bus is attacked, and to filter malicious messages when subjected to flooding attacks. The characteristics of vehicle CAN bus message communication were analyzed, and an intrusion detection method was proposed, which could effectively perform intrusion detection and malicious message filtering. Through experimental verification, the method can detect whether the CAN bus is attacked by 100%, and the accuracy of malicious packet filtering can reach over 99%.

Copyright of Railway Signalling & Communication Engineering is the property of Railway Signalling & Communication Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Test & Measurement Technology is the property of Publishing Center of North University of China and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ordnance Industry Automation is the property of Editorial Board for Ordnance Industry Automation and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Most calibration systems developed in our country for now are based on the CAN calibration protocol(CCP), which is specially designed for the CAN bus, and thus has poor compatibility and expansibility for other buses. However, the protocol layer of the universal measurement and calibration protocol(XCP) is independent from any specific physical transport layer. Based on that, a multi-bus supported ECU calibration system is implemented, which is in accordance with the widely accepted industry norms of measurement, calibration and diagnostic system made by association for standardization of automation and measuring system(ASAM-MCD). The XCP driver is developed in both master and slave nodes, and XCP transport layers for CAN and FlexRay are designed respectively on the basis of the same protocol layer, so that the system is suitable for both the mature CAN bus and the promising FlexRay bus. The system is tested through measurement and calibration experiments, and the results demonstrate that it satisfies the requirements well.

In view of the problem that traditional technology can not meet the requirement of modem automatic control intelligent system with general controllers such as PLC, This study designs an intelligent auxiliary system controller for marine automatic control based on DSP/F28335 by using DSP with high speed, good real - Time performance and built - in CAN controller interface and variable universe PID control algorithm. The system strncture is eitabtisked and the variable universe PID algorithm is introduced. The pe1turbation experiments rule caffied out on the real - time hybrid simulation platform of the system, and the control effect based on the traditional PID controller system is compared. Experiments show that the DSP controller using variable universe fuzzy PID control algorithm greatly improves the real - Time, anti - interference and self - adaplability of the mruine automatic intelligent control auxitiru-y system. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Xinyang Normal University Natural Science Edition is the property of Journal of Xinyang Normal University Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Shanghai University of Engineering Science / Shanghai Gongcheng Jishu Daxue Xuebao is the property of Journal of Shanghai University of Engineering Science Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to solve the problem of loose hosiery products that caused by the poor stability and low real-time performance of the domestic cotton socks machine control system, a control system based on STM32F207 main control chip was proposed. Based on the research of the structure and technology of the cotton socks machine, through the analysis of the key process of the socks machine, especially the trajectory of each step, the overall hierarchical control structure was proposed, and the hardware system of main control chip based on STM32F207 was designed. The control system of the needle selector, air valve and motor board based on Freescale KE06 chip was designed. The data transmission form between the main control and the drive board was designed based on CAN bus protocol. According to the external encoder pulse count, the current needle number and needle position signal were obtained and the zero-detection circuit was designed. The function test was carried out in combination with RUMI WELLKNIT's AOTU RSD model cotton socks machine. The research results show that the designed control system can precisely control the actuator with good coordination, and the accurate needle position capture and the high real-time performance is achieved. The pattern of woven socks is well connected and socks has no detachment or loose. [ABSTRACT FROM AUTHOR]

In view of problems of poor extensibility, single communication mode and difficult locating of fault point existed in current miner's lamp charging monitoring and management system, an intelligent miner's lamp charging monitoring and management system was designed. In the system, charging unit collects miner's lamp condition in real-time, control unit receives the collected data through RS485 bus and transmits it to CAN/Ethernet module through CAN bus, server receives the data through Ethernet,monitoring software displays charging condition according to the data uploaded by the server and sends miner's information to the charging unit. The test results show that the system can accurately collectminer's lamp condition and realize real-time miner's lamp monitoring and miner's information management.

Copyright of Computer Measurement & Control is the property of Magazine Agency of Computer Measurement & Control and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Most of the motor drivers and monitoring sensors used in domestic electric drive precision maize planter are directly connected to the main controller. It’s difficult to expand the number of sowing rows and cannot meet the requirements of variable sowing operation for independent control of each single sowing unit. In order to reduce the coupling of the control system and alleviate the calculation pressure of the main controller, a hardware structure of row-unit controller based on STM32F103 was built, including motor drive circuit and seed quality detection circuit. The P-N 3-phase full-bridge BLDC (brushless direct current) motor drive circuit was based on FAN3278, which could regulate the rotate speed and prevent overload. The seed quality detection circuit was based on photoelectric sensor, which could realize photoelectric isolation and shaping of the sensor signal. The results of signal integrity test indicated that ripple voltage reduced 46.5%, signal transmission of each module was stable and working logic was reasonable. Moreover, a software architecture of the row-unit controller was constructed, the core algorithm included BLDC motor driving program and seed quality detection program was designed. A PID closed-loop control algorithm was used for BLDC motor driver to overcome the shortcomings of open-loop control. The final tuned PID parameter values：Proportional constant was 0.000 04，integration constant was 0.000 3，differential constant was 0.000 01. The results of no-load starting test on BLDC motor indicated that: within a set speed range of 300 -1 800 r/min, the max rise time was 0.4 s and the maximum overshoot was 1.56% on the speed response curve, the start performance met the requirement and speed of motor was improved. The data exchanged between the row-unit driver and the main controller via the CAN bus. The overall test results of the row-unit driver confirmed that it could realize the function of the seed metering driving, the seeding quality detection, and CAN communication with the main controller. The performance test results of seed metering device driving showed that the qualified index was more than 95.7% , the miss index was less than 4.3%, and the multiple index was less than 1.4% when travel speed was 3-9 km/h, which was higher than the national standard GB/T 6973-2005 requirement. The comparison test between the designed single unit driver and seed meter detector for performance evaluation revealed that the detection results were basically coincident. The maximum difference of precision index was only 0.1 percentage points when the speed was 3 km/h. The difference of the qualified index between the seed meter detector and the single unit driver was no more than 2 percentage points, the multiple index was no more than 1.1 percentage points, and the miss index was no more than 0.9 percentage points under different speed gradients. To sum up, the performance of the developed row-unit driver is applicable, and it can be applied in variable rate seeding. [ABSTRACT FROM AUTHOR]

Based on Vehicle Spy 3, an experimental platform for the permanent magnet synchronous motor towing is built. This platform can realize the functions of the data acquisition, data analysis and playback simulation, and communicate with motor controller through the CAN bus. In the experiment of the torque control accuracy, the change of actual motor torque is stable in the range of ±30 N. m after the target torque is increased by the upper computer. In the efficiency experiment of the motor system, the efficiency interval above 80% accounts for 69.7% in the case of electric power and 65% in the case of power generation. This experimental platform adopts the combination of hardware and software, which helps students to master CAN bus technology and enhance their hands-on operation ability, which has high practicability. [ABSTRACT FROM AUTHOR]

Copyright of Computer Measurement & Control is the property of Magazine Agency of Computer Measurement & Control and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To meet the high emission standard and improve the performance of construction machinery,it’s very important to build an engine bench test and carry out performance test. Taking the Cummins QSB6. 7-C220 model engine as object,the function of the engine bench test was analyzed,and the bench test platform was proposed by the way of the dynamometer loading and the measurement of the fuel consumption meter. Based on J1939 protocol,LabVIEW and PEAK USB/CAN card were taken as software development platform and hardware platform, the queue message technology and global variables method were employed to design the monitor software. System tests were carried on the bench test platform. The results indicate that the engine bench test platform can realize the performance test of the engine,the monitor system has a good real-time performance and it can realize the function of automatic parse of J1939 frame data and display of the setting parameters. The monitor system provides a foundation for the flexible engine fuel consumption bench test. [ABSTRACT FROM AUTHOR]

To reduce the error rate and packet loss rate of transmission data in embedded soft PLC system, a circle buffer of embedded soft PLC system was designed, mathematical model of the circle buffer was established. The state equation and the state transition probabilities of the circle buffer were analyzed, and its capacity and the formula of probability of being filled were also discussed. At last, the factors affecting the size of the buffer capacity under different conditions were obtained by simulating, and the relation of data buffer size and the difference between the input stream and output stream were concluded under the premise of no data loss: in the case of other conditions unchanged, the greater the difference between input stream rate and output stream rate, the greater the needed capacity for circle buffer.

For limitations of broadcasting systems of traditional constant-pressure broadcasting, local amplified phone and personal handphone system, the paper proposed a design scheme of voice broadcasting system of coal mine based on Ethernet and CAN bus and introduced structure, design of hardware and software, key technologies of the system. The system can realize remote voice transmission at lower speed and streaming media online broadcasting, which adopts audio codec method of PCM and Ogg Vorbis and Ethernet and CAN bus to transmit data.

UPS is an important solution to power quality problems in power systems. The problem of circulation suppression is the focus and difficulty in the study of multiple UPS parallel technology. Based on the above problems, the parallel control strategy of modular UPS based on CAN bus is proposed. The method uses virtual multi-loop output impedance droop control and CAN bus communication to realize synchronization and current sharing control among parallel UPS modules. The experimental results show that the proposed method not only inhibits the circulation of sub-modules, but also resolves the signal stability problem of distributed system, and ensures the accuracy and real-time data transmission of modular UPS parallel system. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Harbin University of Science & Technology is the property of Journal of Harbin University of Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Computer Measurement & Control is the property of Magazine Agency of Computer Measurement & Control and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Mine Automation is the property of Industry & Mine Automation Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In view of wiring complexity and low reliability of data transmission existed in wired pressure monitoring system of hydraulic support, a pressure monitoring system of hydraulic support based on wireless sensor network was designed. The system takes CC2530 chip as core, collects pressure value of hydraulic support through data collection node. Routing node receives the collected pressure value and sends it to Sink node by multi-hop mode. The Sink node uploads the pressure value to upper computer through CAN bus, so as to realize pressure monitoring of hydraulic support in covered scope of wireless sensor network. The test result shows that the system can realize real-time and accurate monitoring of pressure data of underground hydraulic support.

In view of problems of complex wiring and bad reliability because current driving device of scraper conveyor uses wired detection mode, a wireless detection system of driving device of scraper conveyor based on RFID technology was designed. Parameters collected by various sensors are sent to nRF24LE1 radio frequency module, and the nRF24LE1 radio frequency module sends the data to wireless receiving substation which includes embedded chip S3C4510B through antenna. The wireless receiving substation transmits the data to CAN/Ethernet gateway of roadway through CAN bus. The debugging result shows that the system has high reliability and can detect each parameter of the driving device of scraper conveyor without wire connection.

In view of situation of complexity of coal mine environment and a wide variety of testing nodes and parameters, a coal mine monitoring and control system based on dual network architecture was proposed. According to different monitored objects, the system uses different networks for data transmission, video streaming data uses Ethernet to transmit, mine environment monitoring data adopts CAN network to transmit. Moreover, the dual networks share the same physical line. The system has some advantages, such as the uniform testing and overall networking of all monitored objects, high network utilization and so on.

Copyright of Computer Measurement & Control is the property of Magazine Agency of Computer Measurement & Control and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to solve the traditional computerized flat knitting machined defects existing in the static electric equipment in the test. The CAN bus was used to construct the network de­tection system. The system was detected as the node on the bus with the method of controlling unit with S3F84I9 single chip microcomputer. The communication protocol of CAN bus applica­tion layer was developed and realized by connecting the corresponding interface circuit to the test node. The result shows that the system has good real-time data acquisition, processing and communication functions, and the data processing result can be uploaded to the host computer through CAN bus. Real time monitoring, state detection and on-line fault diagnosis of the static electricity system in computerized flat knitting machine is realized. [ABSTRACT FROM AUTHOR]

The use of large-scale instruments is very important to scientific research, and it should be done to improve instruments utilization rate and reduce the cost of management of the instruments as far as possible. In this paper, based on CAN bus and cloud platform, it was designed the hardware system of STM32F103 core processor and the application of SaaS in real time. The experiment selected the use log of large-scale instruments in East China Normal School to compare the utilization rate with using or without using the system. As a result, it can increase the utilization rate, reduce the cost of management of the instruments and make the laboratory opening personalized. [ABSTRACT FROM AUTHOR]

In view of problems that management of lead-acid battery miner's lamp controlled by labor is inefficient, lamp taking and returning need long time, charging status can not be monitored, and querying is not convenient, an intelligent charging management system for Li-ion battery miner's lamp based on STM32F107 was designed, and designs of hardware and software of intelligent charging interface were introduced. A dedicated Li-ion battery charging management chip BQ24272 with a wide range of DC input was used for intelligent charging interface to realize charging process management. Intelligent charging interface is adapted to charging racks of various types and achieves functions of lamp in position detection, charge control, charging information detection and update, fault alarm, real-time display and communication with PC.

In view of problem that power quality is influenced by factors of short circuit, open circuit, leakage and harmonics, a monitoring system of power quality with multifunction based on DSP was designed. Design of three parts of the system namely front signal collection circuit, lower computer and analyzing software of upper computer were introduced in details. The experiment result showed that the system can real-timely detect and calculate power parameters of voltage, current, power, power factor, frequency and harmonics and it has better monitoring effect.

In order to avoid missing key message caused by sending fault of CAN node in mine-used new energy electric locomotive, a sending fault tolerant method of CAN bus based on TTCAN protocol was proposed, that is, message sent unsuccessfully by CAN node will be resent until the message is sent successfully or resending times reach the maximum resending times. At the same time, a high-efficient receiving and processing message method of CAN bus was proposed. Message is cached during interrupt receiving message, meanwhile, amount of received message is modified, and message in cache is processed by main program based on the modified amount, which realizes time-sharing operation between receiving and processing of message. The test results show that the optimization method can improve real-time ability and reliability of CAN bus communication effectively, decrease working time of CPU in each CAN node and improve working efficiency.

In order to real-timely monitor process parameter of mine-used full hydraulic drilling machine and to realize rapid fault diagnosis of drilling machine, a drilling parameter monitor based on CAN bus was designed, designs of hardware, software and characteristics of the monitor were introduced in details. The monitor adopts distributed control, uses CAN bus to exchange data, not only can real-timely monitor and display pump pressure, rotating speed, pump volume and temperature of fuel tank , oil level and gas concentration, but also can achieve data transmission through computer, which satisfies requirements of site construction.