Design of the hottest infrared remote control car

  • Detail

With the rapid development of electronic technology, infrared remote control has become the most widely used means of communication and remote control. This device has the characteristics of small size, low power consumption, strong function and low cost. Infrared remote control car is widely used in military, civil and scientific research fields. With its powerful control ability, single chip microcomputer provides a practical means to realize this desire. In this design, the infrared remote control car uses 51 single chip microcomputer development board and some simple peripheral circuits as the main driving device, and uses the remote control to control the car for complex movement

1 infrared remote control system

the general infrared remote control system is composed of two parts: transmitting and receiving. It uses special integrated circuit chips for coding/decoding to control the operation. The transmitting part includes keyboard matrix, code modulation and LED infrared transmitter; The receiving part includes optical and electrical conversion amplifier, demodulation and decoding circuit. The schematic diagram of infrared remote control is shown in Figure L

when the transmitter key is pressed, the remote control code will be sent out, and the remote control code will be different with different keys pressed. For this design, the infrared starts to send a l3.5 MS pilot code, which is composed of a 9 ms high level and a 4.5 MS low level, followed by the system code, the system inverse code, the key code, and the key inverse code. If you press and hold the key, the remote control will send a repetition code, which is a high level of 9 ms and a low level of 2.25ms, followed by a short pulse

2. The hardware chip of remote control car

2.1 at89c52

at89c52 is a low-voltage, high-performance CMOS 8-he single chip microcomputer. The chip contains 8K bytes of rewritable flash read-only program memory and 256 bytes of random access data memory (RAM). It is compatible with standard MC to control raw materials from the source and reduce costs s-51 instruction system. AT89C52 single chip microcomputer provides a flexible and inexpensive solution for many embedded control systems

2.2 l298n

l298 is a product of SGS company. It adopts standard TTL logic level signal control and has two enable control terminals. It allows or prohibits the device to work without being affected by the input signal; There is a logic power input, which makes the internal logic circuit work under low voltage. It can be used to drive the DC motor and automatically switch inductive loads such as motor, relay, coil between stepping control rings

3 remote control car circuit design scheme

this design scheme uses AT89C52 to generate high and low levels, which are used to provide L298N to control the motor. Figure 2 shows the circuit design scheme of the remote control car. P2.4 and p2.5 pins in the figure are all levels, and the levels of inl, in2, in3 and in4 are one high and one low respectively, so the two motors can rotate normally

the speed change control of this trolley is realized by relay, and the adjustment can be achieved through the different duty cycle of the relay Average tropical length: for the purpose of 150mm speed

experimental results

after experimental debugging, this design can control the car's forward, backward, left, right, speed regulation, start and stop functions with the remote controller. 1. 2, 3, 4, 5, 6 and 8 are the keys on the remote control

device (as shown in Figure 3)

Table 1 shows the logic function table of remote control car keys,

p2.o ~ p2.5 and p3.5 are the parallel ports on AT89C52

4 summary

the single-chip microcomputer structure and the multitask structure of the software make the system perform multiple operations at the same time, which improves the utilization of CPU and the parent activity of the system. The design has the advantages of light structure, simple operation, convenient maintenance, low cost and high reliability, and has a certain development and utilization prospect

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