feat: runtime examples line_follower

Author: eigen-value

examples/arduino-runtime/blink.py

@@ -12,7 +12,7 @@ def setup():
 
 
 def loop():
-    print('loopy loop')
+    print('blinking LEDs')
     alvik.left_led.set_color(0, 0, 1)
     alvik.right_led.set_color(0, 0, 1)
     sleep_ms(500)

examples/arduino-runtime/line_follower.py

@@ -0,0 +1,60 @@
+from time import sleep_ms
+
+from arduino import start
+from arduino_alvik import ArduinoAlvik
+
+
+alvik = ArduinoAlvik()
+
+
+def calculate_center(left: int, center: int, right: int):
+    centroid = 0
+    sum_weight = left + center + right
+    sum_values = left + 2 * center + 3 * right
+    if sum_weight != 0:
+        centroid = sum_values / sum_weight
+        centroid = 2 - centroid
+    return centroid
+
+
+def run_line_follower(alvik):
+
+    kp = 50.0
+    line_sensors = alvik.get_line_sensors()
+    print(f' {line_sensors}')
+
+    error = calculate_center(*line_sensors)
+    control = error * kp
+
+    if control > 0.2:
+        alvik.left_led.set_color(1, 0, 0)
+        alvik.right_led.set_color(0, 0, 0)
+    elif control < -0.2:
+        alvik.left_led.set_color(1, 0, 0)
+        alvik.right_led.set_color(0, 0, 0)
+    else:
+        alvik.left_led.set_color(0, 1, 0)
+        alvik.right_led.set_color(0, 1, 0)
+
+    alvik.set_wheels_speed(30 - control, 30 + control)
+    sleep_ms(100)
+
+
+def setup():
+    alvik.begin()
+    alvik.left_led.set_color(0, 0, 1)
+    alvik.right_led.set_color(0, 0, 1)
+
+
+def loop():
+    while not alvik.get_touch_cancel():
+        run_line_follower(alvik)
+
+    while not alvik.get_touch_ok():
+        alvik.left_led.set_color(0, 0, 1)
+        alvik.right_led.set_color(0, 0, 1)
+        alvik.brake()
+        sleep_ms(100)
+
+
+start(setup, loop)