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Start Programming

Once you have already Lightning installed, it is time to make some code.

warning

It is necessary to have an IMU sensor in your chassis. If you don't have one, the code will not work.

Testing 🧪​

The easiest way to test Lightning is to run the driver controlled period and see if everything is okay.

  1. Open the main.cpp file of your example project.
  2. Declare your chassis without odometry. You will notice that at the top of the program, there is a declaration of a chassis that already has odometry. For testing purposes, we will delete this declaration.
main.cpp
//Chassis declaration, for Odometry with a one tracking wheel using ADI, ENCODER 
lightning::TankChassis my_chassis( 
 //Odometry configuration
lightning::tank_odom_e_t::ADI_ONE_ODOM,
//Declaration of drivetrain motors
{-11,-12,-13,-14}, //Left side ports (using a negative number will reverse it!)
{20,19,18,17},    //Right side ports (using a negative number will reverse it!)
5,   //IMU port 
pros::E_MOTOR_GEAR_600, //Which motor cartride are you using, blue,red,green? 
3.25, //Wheel Diameter in inches
1.3333, //what is the gear ratio (Is the result of Driven/Driving, Drive:Driving)
{-1,-2}, //Forward ADI ENCODER PORTS (using a negative number will reverse it!), setting -1,-1 would cancel the tracker!
2.507, //Forward tracking wheel  diameter in inches
1.783, //Distance that exist between the forward tracker and the robot rotation center in inches.
{-1,-1},//SIDEWAYS ADI ENCODER PORTS (using a negative number will reverse it!), setting -1,-1 would cancel the tracker!
0, //Sideways tracking wheel  diameter in inches
0); //Forward tracking wheel  diameter in inches

Under this declaration, you will find another declaration that is commented out. This is the declaration we will use for testing. It is a declaration of a chassis without odometry.

main.cpp
/*DECLARATION OF A CHASSIS WITHOUT ODOMETRY
lightning::TankChassis chassis_without_odometry(
  lightning::tank_odom_e_t::NO_ODOM, //No odometry 
  {1,2,3}, //Left side ports (using a negative number will reverse it!)
  {4,5,6}, //Right side ports (using a negative number will reverse it!)
  7, //IMU port 
  pros::E_MOTOR_GEAR_BLUE, //Which motor cartride are you using, blue,red,green? 
  3.25, //Wheel Diameter in inches
  1.3333 //what is the gear ratio (Is the result of Driven/Driving, Drive:Driving)
); */

Uncomment this declaration. You can change the name if desired.

main.cpp
//DECLARATION OF A CHASSIS WITHOUT ODOMETRY
lightning::TankChassis my_chassis(
  lightning::tank_odom_e_t::NO_ODOM, //No odometry 
  {1,2,3}, //Left side ports (using a negative number will reverse it!)
  {4,5,6}, //Right side ports (using a negative number will reverse it!)
  7, //IMU port 
  pros::E_MOTOR_GEAR_BLUE, //Which motor cartride are you using, blue,red,green? 
  3.25, //Wheel Diameter in inches
  1.3333 //what is the gear ratio (Is the result of Driven/Driving, Drive:Driving)
);

  1. Introduce your chassis specifications. For example, if your chasis have the following specifications:

    4 motors by side. Left side motors connection: The left motors needs to be reversed, so, the port is negative!

    • LeftMotor_1 -> -1
    • LeftMotor_2 -> -2
    • LeftMotor_3 -> -3
    • LeftMotor_4 -> -4

    Right side motors connection:

    • RightMotor_1 -> 5
    • RightMotor_2 -> 6
    • RightMotor_3 -> 7
    • RightMotor_4 -> 8

    IMU port:

    • IMU ->9

    Cartride:

    • BLUE = 600 RPM

    Wheel diameter:

    • 3.25 inches

    Gear ratio (Driven/Driving):

    • 1.3333

    With that information, is possible to declare the chassis.

    main.cpp
    //DECLARATION OF A CHASSIS WITHOUT ODOMETRY
    lightning::TankChassis my_chassis(
    lightning::tank_odom_e_t::NO_ODOM, //No odometry 
    {-1,-2,-3,-4}, //Left side ports (using a negative number will reverse it!)
    {5,6,7,8}, //Right side ports (using a negative number will reverse it!)
    9, //IMU port 
    pros::E_MOTOR_GEAR_BLUE, //Which motor cartride are you using, blue,red,green? 
    3.25, //Wheel Diameter in inches
    1.3333 //what is the gear ratio (Is the result of Driven/Driving, Drive:Driving)
    );

  2. Run the driver period 🏎️

    When the driver period is running, you will control your chassis using an arcade configuration! If everything runs well, it means that the chassis declaration is correct.

    note

    You will control the forward and backward direction using the Y-axis of the left joystick, and control the turning using the X-axis of the left joystick.

What is next 🤑?​

I would like to encourage everyone to see learning Lightning as a process. As you start using Lightning, following the tutorials, and gradually reading the documentation, you will become proficient and achieve great results.

It is recommended to start reading and implementing the Lightning Tutorials and start looking the Documentation what it is needed.