Research And Design Of Combination Scale Control System

With the accelerated pace of production automation,when traditional single packing scales weighing items with irregular shapes and uneven quality are time consuming,have higher production costs,and gradually fail to meet the requirements of manufacturers.The combination scale is a good solution to this problem.It adopts the principle of combined weighing,fast speed,high precision,is automatic weighing,reducing the labor,effectively reducing the production cost,improve the production speed and enhance the competitiveness of enterprises.The combination of scales plays an increasingly important role in the automation of production.The performance of the combined scale control system directly determines the performance of a combined scale,so it is very important to study the combined scale control system.The purpose of this project is to design a combination scale control system to achieve automatic combination weighing.Based on the theoretical analysis,this paper analyzes the working princple of the combination scale and constructs the mathematical model of the weighing model using the knowledge of the mathematical statistics.The theoretical analysis shows that the key technology of the combination scale is the guarantee of the weighing precision and the improvement of the weighing speed.In order to improve the accuracy and speed,this paper selects the 24-bit ?-?analog-to-digital converter ADS 1258 chip,the chip 24-bit conversion accuracy greatly improves the accuracy of the weighing data:and the chip in the automatic channel scanning mode sampling speed up to 23.7kSPS.The chip is also compatible with the SPI serial interface,the use of SPI bus protocol can quickly transfer data to the STM32 microcontroller,thereby increasing the weighing speed.In addition,the combination algorithm has been analyzed and studied,and the simulation of the combinatorial algorithm is carried out using Unity3D software,the different results of different conditions are analyzed,and the choice of the algorithm is carried out.The hardware control system mainly includes weighing sensors and transmitter,ADS 1258 analog-to-digital converter,STM32F103ZET6 microcontroller as the core of the main control board module and the host computer MCGS touch screen,stepper motor and driver modules.These modules constitute the hardware support of the control system.On the basis of these hardware,to write the slave computer software system and the host computer touch screen program The control system finally succeeds in realizing the automatic control of the combination scale.