Keywish Hummer-Bot, Инструкция по эксплуатации

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By now, the car can move normally, are you happy and excited? But this is just the beginning, the car
can just fool-turning without significance, there will be more fun if we add it some "organs".Now we will
equip the car with several commonly-used sensors, so it will have a new understanding of the world.
3.2.2 Infrared Obstacle Avoidance
3.2.2.1 Introduction of Infrared Obstacle Avoidance Sensor
Infrared obstacle avoidance module is a pair of infrared transmitting and receiving tubes, the former
launches a certain frequency infrared, the receiving tube will receive the reflected infrared when the infrared
detects the obstacles.After the signal is processed by the comparator circuit, the green LED lights, and the
signal output port outputs digital signal at the same time(a low level signal). The detection distance can be
adjusted through the potentiometer knob, the effective distance range is 2-30cm, the working voltage is 3.3V-
5V.Due to the sensor uses infrared, so the anti-interference ability is very strong, the measurement accuracy
is very high when the distance is moderate. In addition, the module can be assembled easily and used
conveniently, it can be widely used in robot obstacle avoidance,car obstacle avoidance and the black&white
line tracing and many other occasions.
3.2.2.2 Working Principle
1, The module output port OUT can be directly connected with the IO port of the microcontroller, and
directly drive a 5V relay; the connection mode is: VCC-VCC; GND-GND; OUT-IO (A3 and A4), as shown
in Fig.3.2.9 and Chart 3.2.1.
2, The module uses the 3-5V DC power as power supply. When the power is on, the indicator will light.
3, The diameter of installation hole is 3mm, you can use the same size screws (screws in the kit).
Pin wiring definition (only for reference, you can define according to your own ideas):
arduino Uno Infrared Obstacle Avoidance Module
VCC VCC
GND GND
A3 The left module
A4 The right module
Chart 3.2.1 Pin Wiring Definition
3.2.2.3 Module Parameters
The working principle of infrared obstacle avoidance sensor is very simple, that is the reflection property
of objects. In a certain range, if there is no obstacle, the infrared ray emitted will gradually weaken because of
the farther distance of transmission, and finally disappear. If there are obstacles, the infrared will be reflected
to the receiving head. As soon as the sensor detects the signal, it can confirm that there are obstacles in front
of the circuit board, the green indicator will light, the OUT port continuously outputs low level signal to MCU
at the same time, the MCU conducts a series of analysis to ensure that the two wheels of car works properly