Study On Control System Design Of Variable Rate In-line Pesticide Mixing

As the increasing of scale of production in agriculture and forestry, thetraditional way in pesticide pre-mixture puts up its inefficiency and environmentpollution. The shortcoming restricts the development of production, which alsoviolate our national sustainable development. Under the background of developingin precision pesticide application technique and increasing in automation technology,the agricultural and forestry production will be combined with modern automationtechnology and the pre-mixture way of pesticide should be improved. Especially themixing ratio of pesticide and water and the open and close of spraying system shouldbe accurately and automatically controlled. Make sure that there is no extra spraying,no error spraying and promote the agricultural and forestry production to aharmonious stage.Aimed at intelligent toward-target spraying system, a solution on variable ratespraying， accurate controlling in variable rate in-line mixing system was proposed.Using hydraulic control technology and PLC, the excogitation was implemented forthe automatic regulation of spraying parameters during in-line mixture process andtoward-target precision spraying system. With the core of PLC, the article isintended to set up a measurement and control system, design and select relatedhardware and components of hardware in different hydraulic control scheme. Usingladder diagram, the excogitation absorbed the project control system’s feature, suchas conveniently amendment, breaking capacity and stabilization. All parameters ofthe control system was concentrated on three buttons, the other control parameterwas automatically determined by in-line detection.A test platform of variable rate in-line mixing control system was builtaccording to selected hardware, including sensors, nozzles, electric and hydraulicconnection and designing of machining parts. Through the hydraulic control schemedesign of the constant rate pump and the proportional electromagnetic valve,experiments were carried out with data acquisition, on-off control system and flowcontrol system. The experimental results showed that the whole control system ofvariable rate in-line pesticide mixing could achieve the accurate data acquisition, thesteady and rapid on-off control, the precision flow control.