Development Of The Control System For Hole Seeding & Hole Watering-Machine

Basing on a mass of literatures, the article gave out the goal and the task of this design, which is to solve the shortcomings of the hole seeding and watering machine using the technology of computer and the technology of mechanical-electrical integration. And then the scheme of control system is illuminated. The key parts of the system are also introduced in the coming text. At last, the testing control system has come into being.The core of control system is made up of singlechip AT89C51 and its peripheral equipments, and most of the detectors are constituted with the photoelectric sensors. The primary hardware and software of the system are done. The system can change the quantity of the water according to different condition, and work automatically. At the same time, the system can also monitor the working condition of the seeder, and the type and position of the malfunction can be pointed out promptly. To complete the design, the below works and results have been accomplished:1. The circuits of photoelectric detectors have been designed. In comparison with different photoelectric elements, the economical and excellent signal acquired sensor--photoelectric diode has been chosen as signal detector elements. And voltage comparator with retardation has been chosen as the shaping circuit to minish undesired signal and to improve the sensitivity of circuit.2. Has accomplished the control circuit of electromagnetic valve. The control element of the valve adopts the SSR(Sold State Relays), which has the excellent electric interface with singlechip system. At the same time, the protecting circuit of SSR was analyzed. The duration of the valves'opening time is controlled by timers, and this makes it have the function of variable rate watering.3. The startup circuit of electromagnetic valve, which is to ensure the uniformity of seeding, and the machine to synchronize water and seeds have been designed.4. The singlechip system has been designed. This system included the circuit of clock, reset circuit, DC power supply circuit and its monitoring circuit of power. TheμP supervisory circuit, MAX706, is used to improve the stability of the system.5. The circuits of keyboard and display were designed. These parts are using the parallel interface chip 8155 as the I/O interface. The keys are identified through the method of line...