SunFounder picar-x - Line Tracking

SunFounder picar-x
4.5 Line Tracking
This project will use the Grayscale module to make the PiCar-X move forward along a line. Use dark-colored tape
to make a line as straight as possible, and not too curved. Some experimenting might be needed if the PiCar-X is
derailed.
Run the Code
cd /home/pi/picar-x/example
sudo python3 minecart_plus.py
After running the code, PiCar-X will move forward along a line.
Code
Note: You can Modify/Reset/Copy/Run/Stop the code below. But before that, you need to go to source code path
like picar-x/example. After modifying the code, you can run it directly to see the effect.
from picarx import Picarx
if __name__=='__main__':
try:
px = Picarx()
# px = Picarx(grayscale_pins=['A0', 'A1', 'A2'])
px_power = 10
while True:
gm_val_list = px.get_grayscale_data()
print("gm_val_list:",gm_val_list)
gm_status = px.get_line_status(gm_val_list)
print("gm_status:",gm_status)
if gm_status == 'forward':
print(1)
px.forward(px_power)
elif gm_status == 'left':
px.set_dir_servo_angle(12)
px.forward(px_power)
elif gm_status == 'right':
px.set_dir_servo_angle(-12)
px.forward(px_power)
else:
px.set_dir_servo_angle(0)
px.stop()
finally:
px.stop()
How it works?
The grayscale sensor module grayscale_module is also imported in the picarx module, and we can use some of
these methods to detect black lines.
The function to detect the black line looks like this:
4.5. Line Tracking 57