Eye

Introduction

The VR Eye Sensor can detect objects and identify their color, brightness, and hue. It also allows you to adjust detection range and lighting settings for more accurate readings.

Below is a list of all available methods:

Getters – Read object presence, color, brightness, hue, RGB, and sensor status.

• near_object – Returns whether or not a detected object is near the Eye Sensor.

• detect – Returns a Boolean indicating if the Eye Sensor detects the selected color.

• brightness – Returns the brightness of a detected object.

Callback – Run code when an object is detected or lost.

• object_detected – Calls a function when an object is detected.

• object_lost – Calls a function when an object is lost.

Getters

near_object

near_object returns a Boolean indicating whether or not the Eye Sensor is nearby an object.

• True – The sensor is near an object.

• False – The sensor is not near an object.

Usage:
eye.near_object()

Parameters	Description
	This method has no parameters.

def main():
    # Stop driving when Eye Sensor is 
    # near an object
    drivetrain.drive(FORWARD)
    while True:
        if front_eye.near_object():
            drivetrain.stop()
        wait(5, MSEC)

# VR threads — Do not delete
vr_thread(main)

detect

detect returns a Boolean indicating whether or not the selected color is detected by the Eye Sensor.

• True – The sensor detects the color.

• False – The sensor does not detect the color.

Usage:
eye.detect(color)

Parameters	Description
color	The color for the Eye Sensor to check for: BLUE GREEN NONE RED

def main():
    # Stop the robot if the Eye Sensor 
    # detects red
    drivetrain.turn(RIGHT)
    while True:
        if front_eye.detect(RED):
            drivetrain.stop()
        wait(5, MSEC)

# VR threads — Do not delete
vr_thread(main)

brightness

brightness returns the brightness detected by the Eye Sensor as a percent from 0 to 100.

Usage:
eye.brightness(units)

Parameters	Description
units	The unit that represents the brightness: PERCENT

Callback

object_detected

object_detected registers a callback function for when an object is detected.

Usage:
eye.object_detected(callback)

Parameters	Description
callback	A function that is previously defined to execute when the axis’ value changes.

def detected():
    # Display a message
    drivetrain.stop()
    brain.print("object detected")
    wait(0.5,SECONDS)
    brain.clear()

def main():
    # Drive until an object is detected
    drivetrain.drive(FORWARD)
    front_eye.object_detected(detected)

# VR threads — Do not delete
vr_thread(main)

object_lost

object_lost registers a callback function for when an object is lost.

Usage:
eye.object_lost(callback)

Parameters	Description
callback	A function that is previously defined to execute when the axis’ value changes.

def lost():
    # Display a message
    drivetrain.stop()
    brain.print("object lost")
    wait(0.5,SECONDS)
    brain.clear()

def main():
    # Back away from an object
    drivetrain.drive(REVERSE)
    front_eye.object_lost(lost)

# VR threads — Do not delete
vr_thread(main)