# Lesson 1: How to Set Up and Move the Robot

Teachers will guide students through setting up their XRP robot and writing their first Java program to drive it forward and backward using WPILib.

• Students have installed WPILib VS Code and the XRP project template.
• XRP is assembled, connected via WiFi, and flashed with the latest firmware.
• Students are familiar with the Java class structure and basic syntax.

This lesson introduces the XRP’s environment and simple robot movement. Emphasize the structure of WPILib robot projects, focusing on the Robot, RobotContainer, and Subsystem concepts at a high level.

• Robot.java controls the overall robot lifecycle (autonomousInit, teleopPeriodic, etc.).
• RobotContainer.java wires up subsystems and commands.
• subsystems/ folder holds robot hardware logic.
• commands/ folder holds behaviors.

• Open the Driver Station or XRP Web Interface.
• Ensure WiFi connection is active.
• Verify motor control by running the default project.

Create a command to move forward:

package frc.robot.commands;

import edu.wpi.first.wpilibj2.command.Command;
import frc.robot.subsystems.XRPDrivetrain;

public class DriveForward extends Command {
    private final XRPDrivetrain drive;

    public DriveForward(XRPDrivetrain subsystem) {
        drive = subsystem;
        addRequirements(drive);
    }

    @Override
    public void execute() {
        drive.arcadeDrive(0.8, 0.0); // Forward at half speed
    }

    @Override
    public void end(boolean interrupted) {
        drive.arcadeDrive(0, 0);
    }

    @Override
    public boolean isFinished() {
        return false; // Runs until stopped
    }
}

In RobotContainer.java, bind the drive command as the default:

public class RobotContainer {
  // The robot's subsystems and commands are defined here...
  private final XRPDrivetrain m_xrpDrivetrain = new XRPDrivetrain();

  private final CommandXboxController controller = new CommandXboxController(0);

  private final DriveForward driveForward = new DriveForward(m_xrpDrivetrain);

...

  private void configureButtonBindings() {
    m_xrpDrivetrain.setDefaultCommand(Commands.run(() ->m_xrpDrivetrain.arcadeDrive(controller.getLeftY(), controller.getRightX()), m_xrpDrivetrain));
    controller.a().whileTrue(driveForward);
  }

Deploy the code and confirm the XRP moves forward.

• Have students predict what happens when changing the speed sign.
• Let them try using negative values to reverse direction.
• Emphasize stopping motors in end().

• Add rotation: modify drive(0.8, 0.3).
• Add joystick input for control.
• Have students experiment with different speed combinations.

45 minutes (setup + first code run)

• Understand the role of Subsystems and Commands.
• Successfully connect and deploy code to the XRP.
• Control robot movement programmatically.