Eye

Introduction

The VEX 123 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 blocks:

• set eye light – Turn the Eye Sensor’s light on or off.

• set eye power – Set the Eye Sensor’s light power level.

• eye found object? – Returns whether the Eye Sensor detects an object.

• eye detects color? – Returns whether the Eye Sensor detects a specific color.

• eye hue – Return the hue detected by the Eye Sensor.

• eye bright object? – Returns a Boolean indicating if the detected object is bright.

• eye brightness – Return the brightness detected by the Eye Sensor.

set eye light

The set eye light block turns the Eye Sensor’s light on or off.

    set eye light [on v]

Parameters	Description
state	The state of the sensor’s light: on off

Example

  when started
  [Continuously blink the light.]
  forever
  set eye light [on v]
  wait (2) seconds
  set eye light [off v]
  wait (2) seconds

set eye power

The set eye power block sets the brightness of the Eye Sensor’s light. If the light is off, this block will turn it on if the new brightness is not 0%.

  set eye light power to (50)%

Parameters	Description
brightness	The new brightness to set the sensor’s light to from 0% to 100%.

Example

  when started
  [Set the light to different power levels.]
  set eye light power to (25)%
  wait (2) seconds
  set eye light power to (50)%
  wait (2) seconds
  set eye light power to (100)%

eye found object?

The eye found object? block returns a Boolean indicating whether or not the Eye Sensor detects an object within range.

• True – The sensor has detected an object.

• False – The sensor has not detected an object.

  <eye found an object?>

Parameters	Description
	This block has no parameters.

Example

  when started
  [Stop driving after detecting an object.]
  set eye light [on v]
  drive [forward v]
  wait (0.1) seconds
  wait until <eye found an object?>
  stop driving

eye detects color?

The eye detects color? block returns a Boolean indicating whether the Eye Sensor detects a specified color, based on the detected hue value.

• True – The sensor detects the specified color.

• False – The sensor does not detect the specified color.

  <eye detects [red v]?>

Parameters	Description
color	The color to detect: red – A detected hue value between 340°-20°. green – A detected hue value between 80°-145°. blue – A detected hue value between 160°-250°.

Example

  when started
  [Stop driving after detecting a green object.]
  set eye light [on v]
  drive [forward v]
  wait (0.1) seconds
  wait until <eye detects [green v]?>
  stop driving

eye hue

The eye hue block returns the hue detected by the Eye Sensor in degrees from 0 to 359.

  (eye hue in degrees)

Parameters	Description
	This block has no parameters.

Example

  when started
  [Display if an object is pink.]
  forever
  clear all rows
  if <[290] [math_less_than v] (eye hue in degrees) [math_less_than v] [350]> then
    print [Pink!] ▶
    wait (0.1) seconds
  else 
    print [Not pink!] ▶
    wait (0.1) seconds

eye bright object?

The eye bright object? block returns a Boolean indicating whether or not a detected object has a brightness value greater than 70%.

• True – The detected object has a brightness value over 70%.

• False – The detected object has a brightness value less than or equal to 70%.

  <eye bright object?>

Parameters	Description
	This block has no parameters.

Example

  when started
  [Display whether a detected object is bright.]
  set eye light power to (100)%
  drive [forward v]
  wait until <eye found an object?>
  wait (0.1) seconds
  if <eye bright object?> then
    print [Bright object!] ▶
  else
    print [Object not bright.] ▶

eye brightness

The eye brightness block returns the brightness detected by the Eye Sensor from 0% to 100%.

  (eye brightness in %)

Parameters	Description
	This block has no parameters.

Example

  when started
  [Display whether a detected object is bright.]
  set eye light power to (100)%
  drive [forward v]
  wait until <eye found an object?>
  wait (0.1) seconds
  if <(eye brightness in %) [math_less_than v] [70]> then
    print [Object not bright.] ▶
  else
    print [Bright object!] ▶