Research and application of unattended remote metering system

Preface

With the continuous expansion of Laigang's production scale, the number of material measurement sites has also increased. In order to solve the contradiction between the increase in equipment and the relatively small number of personnel, and to optimize and rationally utilize human resources, we decided to learn from the successful experience of unattended substations. After more than three months of hard work, we successfully developed a remote weighing and metering system, and built the first unattended metering station in China with two scales located in the raw material department's freight yard as a pilot. The metering personnel can identify the vehicle number, adjust the position, collect and store data, and print statistics for the vehicles weighed on site from a kilometer away. It has achieved the design requirements of remote control, no need for on-duty, and immersive, laying a solid foundation for the realization of highly intelligent online measurement. In November 2003, the project successfully passed the technical appraisal organized by the Shandong Provincial Department of Science and Technology, and it was believed that the remote measurement monitoring technology has reached the domestic advanced level.

1. Project proposal and plan determination

The development of an unattended remote metering system is mainly to solve the contradiction between the increase in metering sites and the shortage of personnel, and to make technical preparations for the next step of realizing centralized monitoring and online measurement of material measurement. We selected a static track scale and an electronic truck scale located in the Yanzhuang Cargo Factory of the Raw Materials Department as the pilot. The two scales are located at the north and south ends of the cargo yard, about 2 kilometers apart. After visiting the site many times to understand the measurement methods, data flow, logistics varieties and other information of the two scales, we determined that the 60-ton electronic truck scale room located in the office area at the south end of the cargo yard would be the main control room. Monitoring and transmission equipment would be installed in the track scale room to send the audio, video and data signals of the track scale site to the main control room. The measurement personnel in the truck scale room would control and measure the vehicles on the track scale site through the various information received.

2. Working principle and technical features

Using closed-circuit television monitoring and audio and video transmission technology combined with computer network technology, a remote weighing control system integrating image, sound, data and on-site equipment control is established. Successfully applied advanced technologies such as television monitoring, optical fiber communication, and sound and light alarm to the measurement system, completely solved the measurement problems in remote and dangerous environments, realized the on-site unattended measurement method and localized measurement of remote data transmission, and the entire measurement process was remotely controlled (including zero point monitoring and adjustment) without the need for personnel to go to the site for operation. It includes the applications of weighing, security, monitoring, broadcasting, data acquisition, field equipment control, signal transmission, audio and video optical transceiver, etc. It has obvious practicality, safety, reliability and advancement. It can greatly improve work efficiency and reduce production costs. The system has advanced technology, convenient operation, fast operation speed, friendly operation interface, and good versatility. The connection method is shown in Figure 1.

[page]

3. System Overview

The unattended remote metering control system is mainly composed of four modules: field control, safety protection, system control, and system software.

1. The field control part consists of two TC-623 "night owl" low-light automatic aperture cameras, equipped with SSL-06060M ten-fold electric three-variable lens, two photoelectric sensors, an MP-300P power amplifier host, two DSP-108 outdoor broadcast speakers, field metering instruments, and computers. It is responsible for the vehicle number recognition, parking space control, data, audio, and video collection of metering vehicles.

2. The safety protection module is an important part of the system, consisting of a TC-623 "night owl" low-light automatic aperture camera, a TD-223 hemispherical camera, an infrared detection alarm, and an audible and visual alarm, which are used in conjunction with each other. After the far-infrared probe at the door detects the infrared signal emitted by the human body in the restricted area, it starts the indoor camera to record, store and transmit the image, and at the same time, it issues an audible and visual alarm.

3. The system control module is mainly composed of two VADT/R7230 optical transceivers with four-channel video, one-channel audio, and two-channel data, a GECDR-04P "storage king" hard disk recorder, a computer, a broadcast microphone, and a communication optical cable. It is responsible for the sending, receiving, and processing of data, audio, and video. It uses ST optical interface, single-mode transmission mode, PAL format for image transmission, and a two-way RS232 interface for data transmission. It controls the on-site camera and optical transceiver, and completes the PTZ lens control, wiper control, fan control, alarm monitoring, full-screen or frame-sampling recording.

4. The system software is the core of the entire system. The software design is developed using VISUAL BASIC 6.0, an object-oriented visual programming language based on WINDOWS98. It has a friendly interface, is easy to operate, and has strong human-computer interaction. The program is mainly designed for data transmission, so that the program can be operated remotely. It is mainly divided into two parts. One part is the software compilation of the sending end, which is mainly responsible for the information collection and transmission of the metering data. The metering data is received from the instrument and then sent to the computer and then to the optical terminal, and then transmitted to the main control room through the optical cable. The other part is the software compilation of the receiving end. It mainly completes the data reception, maintenance, monitoring, uploading, statistics, printing, query and zero tracking adjustment of the on-site metering equipment. The schematic diagram of the system software composition is shown in Figure 2.

IV. Brief description of the measurement process

When the train enters the track weighing platform, the two cameras installed at the front of the original duty room on site and the photoelectric sensors installed at both ends of the scale body start working, and the measurement data acquisition system automatically starts. The real-time measurement data and the audio and video signals on site are collected, stored and transmitted by the instruments, computers, industrial computers and optical terminals installed on site, and remotely transmitted to the main control room through optical cables. The optical terminal receiver and video industrial computer (hard disk recorder) in the main control room receive, monitor, record and store data image signals in real time, and automatically classify and identify signals and print data statistics. When the vehicle is in an abnormal position, the scale operator can identify it in the main control room through images and photoelectric sensors, and use microphones and speakers installed on site to remind locomotive personnel to adjust the parking position in time.

V. Application effect

Since the system was put into use on June 20, 2003, the system has been running stably, the measurement data is accurate, the audio and video images are clear and stable without jitter, and the anti-theft alarm test has no false alarm or missed alarm. The number of scale operators was reduced from 8 to 4, which improved work efficiency and achieved good economic and social benefits. (end)