Current chapter 11

ch-11/2-speed-control/code.py

@@ -26,7 +26,7 @@ class SpeedController:
     current_ticks = self.encoder.read()
     speed_in_ticks = (current_ticks - self.last_ticks) / dt
     self.last_ticks = current_ticks
-    self.actual_speed = robot.ticks_to_mm(speed_in_ticks) / 1000
+    self.actual_speed = robot.ticks_to_m * speed_in_ticks
     # calculate the error
     error = (Settings.speed * Settings.motors_enabled) - self.actual_speed
     # calculate the control signal

ch-11/2-speed-control/robot.py

@@ -13,10 +13,7 @@ wheel_circumference_mm = math.pi * wheel_diameter_mm
 gear_ratio = 298
 encoder_poles = 28
 ticks_per_revolution = encoder_poles * gear_ratio
-ticks_to_mm_const = wheel_circumference_mm / ticks_per_revolution
-
-def ticks_to_mm(ticks):
-    return ticks_to_mm_const * ticks
+ticks_to_m = (wheel_circumference_mm / ticks_per_revolution) / 1000
 
 motor_A2 = pwmio.PWMOut(board.GP17, frequency=100)
 motor_A1 = pwmio.PWMOut(board.GP16, frequency=100)