The Detection And Control System Of The Seed Gravity-Separator

The screening of seed is an important step during the seed processing. The gravity separator is commonly used in the seed-screening process, which can separate seeds efficiently and filter impurities conveniently according to the weight of seeds and impurities.The traditional gravity separator is handled by the electric and manual way, which depends mainly on the experience of the operator. This makes it hard to guarantee the control precision. In addition, during the screening process, it is often required to manipulate the inverter and multi-motors, including the vibrating motor, the wind motor, the dust motor and at the same time. Therefore, it prevents the improvement of the screening quality because of the complexity of the operation.During the screening process of the gravity separator, the seeds are mainly affected by the supporting force and friction of the sieve bed, the gravity of the seeds and the speed of the inner wind. A dynamic mechanical model was built based on their relationship. The analysis shows that the vibrating frequency of the sieve bed and the speed of the inner wind are two main factors which influent the screening quality significantly. These results are important for the adjustment of parameters. This paper shows the design of the detection and control system of gravity separator with high precision and efficiency. The structure of the hardware is a feedback control system based on the wind pressure and the working frequency of the inverters. In the software design, the control algorithm was developed based on the Qt framework in the Linux OS. In order to actualize real-time signal processing and improve the response speed, a multi-thread design was implemented where independent threads are designed for the sensor, the actuator, the inverter and so on. The interactive devices of the control system are a touch screen and an Android application running on mobile phones. Two operation modes are provided, including the expert mode and the customer mode, to meet different needs.Based on the research of the parameter adjustment, innovative ways of control and interaction are utilized and enhance the level of intelligence and automation of the process.