



| Line Tracer Program (Kitae Kim) | ||||||||||||||||||||||||||||||||||||||||
| | ||||||||||||||||||||||||||||||||||||||||
| Fireworks Photo Caption ================================================= Second, following picture is motor controller part. center processing part. | 1. This robot can follow the line. That is why we call this robot line tracer robot. 2. This robot consists of three parts: center processing part, sensor part, and motor controller part. In this sensor part, there are 8 light sensors. 1 light sensor consists of two sensors: lighting-emitting sensor, lighting-receiving sensor. The color of lighting-emitting sensor is white and lighting-receiving sensor is black. First, lighting-emitting sensor emits the light, and then if lighting-receiving sensor receives the light, it send signal to microprocessor. In the picture, the squares that bring out the blue color are variable resistors. So, we can control the degree of the sensitivity for sensors. Finally, the sided figures that bring out the black color are LM324 chip. This chip makes the signal that is gotten from sensors to amplify in order to be suitable for the microprocessor. This motor controller part is made up of two circuits, but both of them are same circuit. I’ve used step motor for this robot. Step motor is very popular motor. It move 1.8 degree each signal. So, we can control exactly the speed of revolution. To control step motor, we have to use SLA7024 chip and L297. L297 divide the signal that microprocessor sends into 4 signals, and each signal is come into SLA7024. SLA7024 make step motors to move according to each signal. This picture is SLA7024 circuit. I’ve used AT89C52 chip for this robot. This is 8051 chip series. This is the circuit diagram of 8051 chip. This chip is 8-bit CPU optimized for control applications. It usually has 4k byte Rom (mine has 8k byte Rom) and 128 byte Ram (mine has 256 byte Ram). Also, we can use the maximum 24 pin for controlling some applications. If sensor is human’s eye or ear and motor is human’s feet, this part is like brain for this robot. In this part, 8051 chip (brain) calculates the number of rotation by using the data that sensors send. After that, 8051 chip sends signals to motor controller part. 3. The parts used for this robot
4. This robot needs at least 5~6 volts. Also, to turn wheels, it needs over 1A. I think that voltage should be 10~12 volts, and Current should be 1~2A. |