Innovative development from the RedRobots team – block normalization of raw values from EV3 color sensor in light mode! No longer have to suffer with different values on the two sensors, they can be normalized using this block.
Every LEGO Light Sensor is unique meaning that there are considerable value variations in measurements taken between different LEGO sensors. Normalization is the process of adjusting values measured on different scales to a notionally common scale, in our case 0 to 100.
Eliminating light measurement variations, results to a more robust line follower. In order to bring all light sensors we use, to the same scale and also have a wide value range ie 0 to 100 of readings, the following scheme is used:
maxValue : is the Light measured on White color
minValue : is the Light measured on Black color
Normalised Light = (light − minValue ) / (maxValue − minValue ) * 100
for light measured = minValue , numerator becomes (minValue – minValue ) = 0 and for light = maxValue , becomes (maxValue − minValue ) / (maxValue − minValue ) ∗ 100 = 100
Comparison with a standard block inside “MyBlock”:
Reflected light Sensor block
|Ability to read raw values||This feature is not provided by EV3-G developers ||One of the modes of this custom block |
|Normalizing values (discretion)||Only using My Block, and decreasing the discreteness of values (division)|
The difference between white and black is always less than 100, due to this the illumination is scaled.
|Normalization is one of the block modes, and increases the discreteness|
The difference between white and black is always greater than 100 (in practice, about 250), due to this, the discreteness increases, fractional values appear, for example, “10.5% of illumination” becomes normal.
Rate of normalization (conversion)
About 850 times per second
About 1600 times per second
|Calibration of each sensor individually|| This feature is not provided by EV3-G developers||One of the modes of the block, with the ability to select the port|
Cost & Buy now
Block for EV3-G: 74.99 USD
Pay now (via PayPal service):