# Then measure their color with the hsv() method,
# as shown in the previous example. Write them down
# as shown below. The name is optional, but it is
# useful when you print the color value.
green = Color(h=132, s=94, v=26, name='GREEN_BRICK')
magenta = Color(h=348, s=96, v=40, name='MAGENTA_BRICK')
brown = Color(h=17, s=78, v=15, name='BROWN_BRICK')
red = Color(h=359, s=97, v=39, name='RED_BRICK')
# Put your colors in a list or tuple.
# Including None is optional. Just omit it if
# you always want to get one of your colors.
my_colors = (green, magenta, brown, red, None)
# Save your colors.
sensor.detectable_colors(my_colors)
# color() works as usual, but it only
# returns one of your specified colors.
while True:
color = sensor.color()
# Print the color.
print(color)
# Check which one it is.
if color == magenta:
print("It works!")
# Wait so we can read it.
wait(100)
"GREEN": 20,
"BLUE": 110,
"RED": 200,
"YELLOW": 290,
"BLACK": 250,
"WHITE": 75,
"NONE": 162,
}
# Verify saturated colors without calibration.
for name in ("GREEN", "BLUE", "RED", "YELLOW"):
motor.run_target(SPEED, angles[name])
detected = color_sensor.color()
assert detected == Color[name], "Expected {0} but got {1}".format(
Color[name], detected)
# Update all colors.
for name in angles.keys():
motor.run_target(SPEED, angles[name])
Color[name] = color_sensor.hsv()
# Set new colors as detectable colors.
color_sensor.detectable_colors([Color[key] for key in angles.keys()])
# Test all newly calibrated colors.
for name in angles.keys():
motor.run_target(SPEED, angles[name])
detected = color_sensor.color()
assert detected == Color[name], "Expected {0} but got {1}".format(
Color[name], detected)
class ExplorationRover():
"""Control the Mars Exploration Rover."""
# In this robot, we want to detect red and cyan/teal "mars rocks".
ROCK_COLORS = (Color.RED, Color.CYAN)
# These are the gears between the motor and the rear wheels.
REAR_GEARS = (8, 24, 12, 20)
# An animation of heart icons of varying brightness, giving a heart beat.
HEART_BEAT = [
Icon.HEART * i / 100
for i in list(range(0, 100, 4)) + list(range(100, 0, -4))
]
def __init__(self):
# Initialize each motor with the correct direction and gearing.
self.left_rear_wheels = Motor(Port.E, Direction.CLOCKWISE,
self.REAR_GEARS)
self.right_rear_wheels = Motor(Port.F, Direction.COUNTERCLOCKWISE,
self.REAR_GEARS)
self.left_front_wheel = Motor(Port.C, Direction.COUNTERCLOCKWISE, None)
self.right_front_wheel = Motor(Port.D, Direction.CLOCKWISE, None)
# Initialize sensors, named after the Perseverance Mars Rover instruments.
self.mast_cam = UltrasonicSensor(Port.B)
self.sherloc = ColorSensor(Port.A)
# Initialize the hub and start the animation
self.hub = InventorHub()
self.hub.display.animate(self.HEART_BEAT, 30)
def calibrate(self):
# First, measure the color of the floor. This makes it easy to explicitly
# ignore the floor later. This is useful if your floor has a wood color,
# which can appear red or yellow to the sensor.
self.floor_color = self.sherloc.hsv()
# Set up all the colors we want to distinguish, including no color at all.
self.sherloc.detectable_colors(self.ROCK_COLORS +
(self.floor_color, None))
def drive(self, speed, steering, time=None):
# Drive the robot at a given speed and steering for a given amount of time.
# Speed and steering is expressed as degrees per second of the wheels.
self.left_rear_wheels.run(speed + steering)
self.left_front_wheel.run(speed + steering)
self.right_rear_wheels.run(speed - steering)
self.right_front_wheel.run(speed - steering)
# If the user specified a time, wait for this duration and then stop.
if time is not None:
wait(time)
self.stop()
def stop(self):
# Stops all the wheels.
self.left_rear_wheels.stop()
self.left_front_wheel.stop()
self.right_rear_wheels.stop()
self.right_front_wheel.stop()
def scan_rock(self, time):
# Stops the robot and moves the scan arm.
self.stop()
self.left_front_wheel.run(100)
# During the given duration, scan for rocks.
watch = StopWatch()
while watch.time() < time:
# If a rock color is detected, display it and make a sound.
if self.sherloc.color() in self.ROCK_COLORS:
self.hub.display.image(Icon.CIRCLE)
self.hub.speaker.beep()
else:
self.hub.display.off()
wait(10)
# Turn the arm motor and restore the heartbeat animation again.
self.hub.display.animate(self.HEART_BEAT, 30)
self.left_front_wheel.stop()
