3A: LED

LED stands for “light-emitting diode”. A diode is an electronic device that allows an electronic current to flow in only one direction. LEDs are beginning to replace traditional light bulbs because they are more efficient.

Your CoDrone Mini has 1 RGB LED on the main body. RGB stands for red, green, and blue. Using the three colors, you can create almost every color imaginable! Aside from making your drone look cool, LEDs provide another form of feedback. A solid LED means your drone is connected, while a flashing LED means the battery is low or CDM is disconnected from the remote.

The most basic LED function that you can use is LED_color. This will set your CoDrone Mini’s LED to one color using the RGB colorspace. Don’t worry — we’ll get to that soon.

This is what the function looks like:

LED_color(red, green, blue, brightness)

This is what each of the parameters means:

• Red, green, blue: an LED produces a color as a combination of red, green, and blue, or RGB for short. All of these values range from 0 to 255 corresponding to the color’s intensity, with 255 being the highest. For example, the RGB values for the color red correspond to (255,0,0). What are the RGB values for blue and green? What about purple? Use an RGB color picker like this one to find out! Once you know what you want your LED’s color to be, enter the RGB values into the corresponding spaces in the parentheses.
• Brightness: How bright the LEDs are, with 1 being off and 100 being maximum brightness. The brightness value will never be negative!

Try this program out to see what a solid LED looks like. We programmed ours to show red, green, and blue, but you can use whatever colors you like.

import CoDrone_mini

import time



drone = CoDrone_mini.CoDrone()

drone.pair()



drone.LED_color(255, 0, 0, 100)   # Red     

time.sleep(1) 

drone.LED_color(0, 255, 0, 100). # Green

time.sleep(1)

drone.LED_color(0, 0, 255, 100). # Blue

time.sleep(1)

 time.sleep()  is there to show each LED for 1 second before moving on to the next line of code. Change the sleep() parameter to show each color for a longer or shorter time.

If you think the solid LED function is too basic, we see you. The pattern LED function helps you set your CoDrone Mini’s LED to both a color and one of three patterns. This is what it looks like:

LED_pattern(red, green, blue, mode, speed)

This is what each of the parameters means:

• Red, green, blue: just like the solid LED function, this is where you set your LED’s color using the RGB colorspace.
• Mode: also known as the pattern. You have three to choose from:
  • BLINK flashes LED on and off
  • DOUBLE BLINK flashes LED on twice before turning off
  • PULSE turns LED on and off slowly
  • FADE_IN increases the brightness of the LED from low to high
  • FADE_OUT decreases the brightness of the LED from high to low
• Speed: this is the speed of the LED’s pattern. 1 is the slowest and 10 is the fastest. This value will never be negative! If you don’t include this parameter, your program will use the default value, which is 5.

Try this program to see what the different LED programs look like. Again, we used red, green, and blue, but you can use whatever colors you like!

import CoDrone_mini

from CoDrone_mini import Mode

import time



drone = CoDrone_mini.CoDrone()

drone.pair()



drone.LED_pattern(255, 0, 0, Mode.BLINK, 10)

time.sleep(1)

drone.LED_pattern(0, 255, 0, Mode.DOUBLE_BLINK, 10)

time.sleep(1)

drone.LED_pattern(0, 0, 255, Mode.PULSE, 10)

time.sleep(1)

drone.close()

If you’re done with your LED or want to set it back to its default, there are two functions for that:

• turn_off_LED(): turns the LED off. Perfect if you’re trying to go undercover.
• reset_LED() : resets the LED back to its default, which is solid red.

Try using them at the end of one of your programs!

To add LEDs to a flight program, insert the LED functions where you want to see them in your program. The only exception is if you’re setting your LED before takeoff. If you do this, you need to add time.sleep(1)right before your takeoff command so takeoff isn’t skipped.

import CoDrone_mini

import time


drone = CoDrone_mini.CoDrone()

drone.pair()


drone.LED_color(255, 0, 0, 100)

time.sleep(1)       # Add a time.sleep(1) before takeoff if you're planning to set the LED cover before takeoff, otherwise the takeoff might get missed

drone.takeoff()


drone.set_throttle(50)

drone.move(1)


drone.LED_color(0, 255, 0, 100)

drone.set_yaw(50)

drone.move(2)

drone.LED_color(0, 0, 255, 100)

drone.set_yaw(50)

drone.move(2)


drone.land()

drone.close()

I Can See A Rainbow

Draw a rainbow in the air with your CoDrone Mini! A rainbow has 6 colors (7 if you count indigo). There are a couple of ways to do this:

• Draw 6 or 7 different colored arcs
• Draw one long arc with a color for each section