As shown in above figure there is a motor that rotates the belt. Various sensors are placed on belt to sense the position of moving container. Various controls are available for motor Forward - when it is applied positive pulse the motor will start rotating clockwise and the container on belt will move ahead
Reverse - when it is applied positive pulse motor will start rotating anticlockwise and the container will move back Stop - when it is applied positive pulse motor will stop and container will be steady
Speed - this will change the speed of belt as the voltage applied to this pin is varied from 0 - 5 V
One more control is drop Drop - the items will drop from the nozzle till this is applied high logic (5V)
So all above are the inputs of this conveyor belt system. Now let us see the outputs. There are four outputs and they are from various sensors placed on belt. Sensor 1,2 & 3 o/p - it gives high output as container reaches to it. Sensor 4 o/p - it generates positive pulses as items dropped from nozzle. So depending upon this input and output we have to design a circuit that will control this conveyor belt. Let us first see the block diagram of system