Let PiCar-X Move

This is the first project, let’s test the basic movement of Picar-X.

Run the Code

cd /home/pi/picar-x/example
sudo python3 move.py

After running the code, PiCar-X will move forward, turn in an S-shape, stop and shake its head.

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.

import sys
sys.path.append(r'/home/pi/picar-x/lib')
from utils import reset_mcu
reset_mcu()

from picarx import Picarx
import time

if __name__ == "__main__":
    try:
        px = Picarx()
        px.forward(30)
        time.sleep(0.5)
        for angle in range(0,35):
            px.set_dir_servo_angle(angle)
            time.sleep(0.01)
        for angle in range(35,-35,-1):
            px.set_dir_servo_angle(angle)
            time.sleep(0.01)
        for angle in range(-35,0):
            px.set_dir_servo_angle(angle)
            time.sleep(0.01)
        px.forward(0)
        time.sleep(1)

        for angle in range(0,35):
            px.set_camera_servo1_angle(angle)
            time.sleep(0.01)
        for angle in range(35,-35,-1):
            px.set_camera_servo1_angle(angle)
            time.sleep(0.01)
        for angle in range(-35,0):
            px.set_camera_servo1_angle(angle)
            time.sleep(0.01)
        for angle in range(0,35):
            px.set_camera_servo2_angle(angle)
            time.sleep(0.01)
        for angle in range(35,-35,-1):
            px.set_camera_servo2_angle(angle)
            time.sleep(0.01)
        for angle in range(-35,0):
            px.set_camera_servo2_angle(angle)
            time.sleep(0.01)

    finally:
        px.forward(0)

How it works?

The basic functions of PiCar-X are in the picarx.py program file, under the path /home/pi/picar-x/lib. The picarx.py program is used for controlling the servo and wheels, and will make the PiCar-X move forward, turn in an S-shape, or shake its head.

Now, the libraries to support the basic functionality of PiCar-X are imported. These lines will appear in all the examples that involve PiCar-X movement.

import sys
sys.path.append(r'/home/pi/picar-x/lib')
from utils import reset_mcu
reset_mcu()

from picarx import Picarx
import time

The following function with the for loop is then used to make PiCar-X move forward, change directions, and move the camera’s pan/tilt.

px.forward(speed)
px.set_dir_servo_angle(angle)
px.set_camera_servo1_angle(angle)
px.set_camera_servo2_angle(angle)

• forward(): Orders the PiCar-X go forward at a given speed.

• set_dir_servo_angle: Turns the Steering servo to a specific angle.

• set_camera_servo1_angle: Turns the Pan servo to a specific angle.

• set_camera_servo2_angle: Turns the Tilt servo to a specific angle.