Remote Control

You may be wondering how to use the keyboard to control CoDrone. In the first activity, you will learn how to use your spacebar to turn on your CoDrone LEDs. In Junior mode, you can select a color. In Senior mode, you will be using the RGB values of your color. 

First, turn off your CoDrone LEDs at the start of your program. You can do this by setting the brightness of the color of your choice to the lowest value, 1.

Since you want your program to constantly check if you are pressing a key, you will need to implement a forever loop. For this example, use a repeat loop block and connect an “is_code_running()” block from the orange status checkers menu.

Now it’s time to check for keyboard input! Remember that when a program needs to make a decision you will use a conditional statement. Go to the logic menu and grab a conditional block. In the keyboard menu, grab the “When backspace key press” that has the attachment on the side. From the drop-down menu, select “spacebar”.

If the spacebar is pressed, you want your CoDrone LEDs to turn on. Else, turn them off by resetting the brightness back to 1.

You will need to add a wait block after the conditional statement. This is because if you press and hold the spacebar, you will be sending multiple messages to CoDrone. A delay of 500 milliseconds will be enough to prevent CoDrone from disconnecting.

If you want to check for multiple key presses, you will need to include an else if statement for every extra key press.

Now that you have the basic idea, instead of changing LEDs, you will be adding flight commands! First, you will set up the structure of the program to handle roll, pitch, yaw, and throttle. Since there are positive and negative values for each flight direction, there are 8 total possible commands plus the spacebar for the emergency stop.

In this example, the following keyboard commands will be used, but you can change the values to whatever you want. 

• W/S- Positive/Negative throttle 
• D/A- Positive/Negative Yaw 
• Up/Down- Positive/Negative Pitch 
• Right/Left- Positive/Negative 
• Space- Emergency stop 

Think about how you should program your if statements. Remember that if and else-if are useful when you only want to execute one of those commands. However, using one if statement and 7 if-else statements means you can only fly in one direction at a time! To be able to fly in more than one direction, you need to group your if statements into roll, pitch, yaw, and throttle. For example: 

If W is pressed, set Throttle to 75 2 

Else if S is pressed, set throttle to -75 3

Else, set throttle to 0.

The else statement is very important. It resets the value of throttle to zero whenever neither key is pressed.

Activity: Obstacle course 

Now that you have your new flight controller, build an obstacle course and try to fly to the finish line without hitting anything! If you need to, adjust the values of the delays and add more keys for more functionality.