Intelligent remote control car based on Liangshan School

# **Function introduction**
#### 1. Bluetooth wireless remote control
#### 2. Four-way motor drive
#### 3. Buzzer alarm reminder
#### 4. Five channels at the front of the car, one on each side Infrared tracking
#### 5. Ultrasonic obstacle avoidance all the way
#### 6. Independent button to switch sports mode


# **Function details**
### 1. Bluetooth wireless remote control, using HC-06 Bluetooth module, through the serial port Communicate with MCU to remotely control the direction and stop of the car.
![Bluetooth module front.jpg] ![Bluetooth module back.jpg]

### 2. The four-way motor driver uses the RZ7899 chip. The maximum current in the instruction manual of this chip is 6A. It is said that it will burn when it reaches about 2A. The speed can be controlled by controlling the two input pins through the PWM signal, and the forward and reverse rotation of the motor can be controlled by reversing the voltage. However, it should be noted that the frequency of the PWM should not exceed 1KHz. It is said that it will burn (you can try doge ), so I chose the 100HZ frequency. The motor uses an N20 reduction motor, and the store said it has a speed of 100 rpm (if you buy a smaller one, it will turn slower).

### 3. The buzzer is used to prompt whether a button is pressed. Once pressed, it will sound briefly.

### 4. The first five channels of infrared are used to detect the direction of movement and the finish line. The left and right lanes are numbered in grids (like the grids of venues like industrial training competitions).
![Front of the tracking module.jpg] ![Back of the tracking module.jpg] ### 5. The ultrasonic module uses the HC-SR04 module, which is used as a sensor for obstacle avoidance during tracking. The working principle is to obtain the propagation time through the emission and reception (reflection) of sound waves, and then calculate the distance from the object through the formula.
![Ultrasonic module.jpg] ### 6. Two independent buttons are used to switch the mode of the car. Button 1 (Start) controls the switch of the tracking mode. When pressed once, the buzzer will sound. When tracking, In tracking mode, the LED above it will be always on, and then tracking will begin. The tracking mode of start button 2 (MODE) will switch to Bluetooth control mode, and the LED above it will also be always on. You can control the car and switch modes through the mobile phone PC APP. (The original button was broken, and there were only small buttons around, which were forcibly welded on)
![Button.jpg]
## **Some beautiful photos of the car**
![IMG_20221221_214155.jpg] ![IMG_20221221_214141.jpg] ![IMG_20221221_214132.jpg ] ![Backside of car.jpg] ## **_I wrote the code using the HAL library, and the project is in the attached .7z file_**
# Note
## You can see that I used Dupont lines to fly out a few lines. The reason is that I didn't notice the conflict between the downloader pins when I first started doing it. When doing tracking, I need to avoid the four pins of the downloader. The schematic and code will be updated when available.
## 2023-3-7 Updated the schematic diagram and PCB, changed some packages, and reduced the number of headers for testing.
## 2023-3-22 At the buzzer module in the schematic diagram, replace the original 10K pull-up resistor with 4.7K (only use 10K for 5V voltage, otherwise the buzzer will not sound). CubeMX updates the configuration. The previous configuration will cause The program cannot be downloaded. If the direction of the motor is opposite to expected, it can be installed in the opposite direction.