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Getting best out of Color Sensors

Question 1: Should I always calibrate my Color Sensors?
Answer: No. You should use your sensors directly. First thing that you may want to do with
your color sensors is to simply test whether these are detecting right colors. This might
be done by a simple program that reads and prints the sensor values on the LCD screen. Following values should be seen (for different colors):
b - Blue, r-Red, y-Yellow, g-Green, x-Black, w-White, A&Z - Out of range
If your program is detecting right colors, you need not calibrate your sensors.
 
Question 2: Are there any mounting guidelines?
Answer: Yes, mounting of sensors is very important. First and foremost is to use only the
small screws provided with the sensor casing must be used. Using longer screws and forcing
them for fitment can damage, and impact the behaviour of the sensor. Height of Sensor (it's distance from surface) matters and result could be different for different heights. It is recommended that these sensors are kept as close as possible to the surface or at a height of less than or equal to 1 cm, for best results. Also, mount height of sensor, while calibrating and while actual use, should
be similar.
 
Question 3: Where are the calibration values stored, in the hardware or Brain unit?
Answer: Calibration values are per port and saved into your computer (on which Robo G3 is installed) and are burnt into the brain unit with your program. So, if you want to connect color sensors to ports 3 and 4 and need to calibrate, you should calibrate for both the ports individually. Also, please understand that if you calibrated one sensor by connecting it to port 3 and again calibrate another sensor on the same port 3, the earlier calibration values will be overwritten.
 
Question 4: Why does my Brain unit doesn't start after calibration?
Answer: For calibration, Robo G3 software burns a special program into the brain unit. So,
it is very important to burn your own program to the brain unit to make it function for you.
If you don't want to use brain unit for programming, you should still burn a simple program
with simple Start and stop control blocks to use it.
 
Question 5: What are the values shown in the calibration window against the color patch?
Answer: Color sensor module, if you see has four white color LEDs and an array of photo diodes. For color
detection, it transmits the light on the object and reflected light of the object is
detected by these photo diodes, which in turn generate varied frequency pulses for different colours. The values shown
are the normalized counts based on these colour frequencies as calculated by the brain unit.
 
Question 6: In what conditions I should calibrate my sensor?
Answer: Color sensors are very much dependant on the ambient light and hence we should
consider calibration only when you feel the difference in Ambient light is significant and
can impact the reflected light of the LEDs. Still, refer to Question 1 before taking a call
on whether to do calibration or not.
 
Question 7: With what kind of props, I should calibrate my Colour sensors?
Answer: This answer depends on application usage for the sensors. Your calibration props should be similar to the how the end use of sensors will be. For example, if it's for IRC prep, your prop should be of similar material and gloss as used for IRC arena. As a guideline, as explained in Question 1, have a test program handy, and use that program first to see if you really need calibration. If yes, calibrate it on the calibration area of Arena.
 
Question 8: Are there any specific colour sensors that shouldn’t be calibrated?
Answer: All colour Sensors that are provided with E-Series brain unit are compatible and Calibration option can be tried.

Question 9: Are there any updates to the Calibration Software?
 
Answer: There is active development going on to make Robo G3 software more feature rich and you should remain in sync with the new changes happening. Refer to this page for more info on what’s latest: https://www.avishkaarbox.com/robo-g-3-beta