This design is an intelligent traceability system, which uses intelligent platform to realize fully intelligent traceability of shock absorber assembly, effectively control the cost of traceability and reach the domestic advanced level. The system framework is shown in Figure 1.
The main research and development contents of the traceability system are divided into two parts: hardware and software. Among them, the main contents of the hardware part are as follows.
1.1 SCADA (Supervisory Control And Data Acquisition data acquisition and monitoring control system)
At present, the stations involved in the assembly line and the data to be collected are: the cleaning machine needs to collect the cleaning temperature, rinsing temperature, torque and displacement of the wire feeding machine; Riveting force of stop riveting machine; Oil filling quantity of oil filling machine; Time and displacement of indicator; Pressure of sealing machine; Inflating pressure and rebound force of inflator; Pressure and displacement of working cylinder bottom valve press machine, etc. For these stations, we can add corresponding sensors or communication modules. PLC can adopt small S7-1200 or S7-200 Smart, and add analog input and output modules.
1.2 Scan code of incoming materials and code into SCADA system
In the process of vehicle parts and other intelligent assembly lines, firstly, the bar code should be printed on the main parts, and then the bar code information should be stored in the industrial computer database. For each barcode, it is the unique identifier of each product. No matter where the product is sent, there will be recorded information in the barcode. When there is a problem with the product, the relevant information of the product can be found in the corresponding database by scanning the barcode, thus solving the problems of after-sales service and quality tracking.
In this item, you can scan codes individually or in batches. For the installation of code scanning equipment, one part should be fixed and can scan code accurately from a single angle, and the other part should be movable to realize multi-angle code scanning. High sensitivity is required for code scanning equipment, and both command control and automatic scanning modes are supported. Avoid the unstable scanning condition of barcode scanning equipment [2].
In the process of scanning code, the product code will be constantly adjusted according to the actual needs. If the barcode length is too long, it is necessary to shorten the barcode length or change it to a two-dimensional code; The paste position of bar code should be fixed and unified, because the fixed scanning code requires more accurate bar code position, otherwise it will not be scanned easily. It is necessary to use the stop switch on the assembly line to control the code scanning, and all stops and stops should be able to be used normally, as shown in Fig. 2. In this design process, the original two-dimensional code requires the last six digits to be numbers, but now the requirement is that the last digit remains unchanged, adding 1 to the middle four digits, and sweeping the previous date. The problem of repeated scanning is due to the high speed of the transmission line or the low sensitivity of the scanning gun. The QR code is shown in Fig. 3 below.
The scanning gun of each station cannot be exchanged casually, and the prefix of scanning gun of pressure displacement station of bottom pressing valve is B; The prefix of the recovery valve station scanner is C; The prefix of the indicator station scanning gun is D; Sealing station scanner prefix is E; The prefix of inflation station scanning gun is F.
The specific settings of the code sweeper are as follows: A baud rate is 9600, data is 8, stop bit is 1, check bit is not available, flow control is not available, and suffix and prefix is not available, and B is set to always-on mode.
1.4 IP allocation of each device
The equipment communicating through Ethernet in this design includes industrial computer, PLC, power indicator, oil injection machine and recovery valve. The IP distribution is shown in Table 1.