[LiChuang Development Board] Multi-mode smart car based on Liangshanpai development board

## **This is a smart car based on Liangshanpai GD32F450 chip. The schematic diagram can be found on the official website of LiChuang. LiChuang EDA Professional Edition is used for PCB production. **
### Core board module:
###### The core board uses Liangshanpai module, which has rich pins, complete functions and is compact and portable, allowing developers to learn and use it anytime, anywhere.
### Power module:
###### The power supply uses two 18650 batteries, each providing a voltage of 3.4V. Use 7.4V to power the motor.
####### Motor drive module: The motor drive module uses four rz7899 chips. The operating voltage of the chip is 3-25V, and the maximum output current can reach 3A, which is very suitable for high-speed racing. The motor is driven by four N20 motors. The driving voltage is 7.4V.
### Bluetooth module:![d8418778f944b0b0b0c8d8a27160445.jpg] ###### The Bluetooth module uses the HC-05 module. By designing a Bluetooth APP connected to it, the Bluetooth control car drive can be realized.
### Ultrasonic module:![1b686caff0b724a79d03680288f8bba.jpg] ###### The ultrasonic module uses the HC-SR04 module, which measures the distance through ultrasound and detects whether it encounters an obstacle by judging the distance.
### Tracking module:
###### The tracking module uses five ITR9909 modules. The module determines whether there is a black line by emitting and receiving infrared light. If there is a black line, the black line will not reflect infrared light, and the ITR9909 at the corresponding position will not receive infrared light, so it can be determined that it is on the black line.
### Power display module:
###### The power display module detects the power through the ADC module.

### Project optimization points:
Several problems were encountered during the PCB drawing process:
1. The line width setting size problem, the signal line is 10mil, I personally feel that it is affected by the motor, and there is a problem of unstable signal transmission. Modification suggestion: The board margin is relatively spare, the reserved camera module can be discarded or the 15mil line can be passed through in a detour.
2. In the power supply part, the power supply on the top layer is transferred to the bottom layer after passing through the switch. The number of 7.4V vias in this place is small. Appropriate vias can be added on the right side of R1 to avoid heating problems. ![微信图片_20230513211949.png]