Teleop Introduction

The TeleOp period

An FTC match has a 30 second autonomous period followed by a 2 minute driver-controlled period. The last 30 seconds of the driver-controlled period is the end game. TeleOp is the OpMode that runs during the driver-controlled period.

The OpMode loops continuously, reading the gamepads and updating motors and servos each pass.

Gamepads

Two gamepads connect to the Driver Station. By convention gamepad1 is the driver, who moves the robot, and gamepad2 is the operator, who runs the mechanisms.

double forward = -gamepad1.left_stick_y;
boolean clawClose = gamepad2.a;

Inputs:

• Sticks: left_stick_x, left_stick_y, right_stick_x, right_stick_y. Range -1.0 to 1.0.
• Triggers: left_trigger, right_trigger. Range 0.0 to 1.0.
• Bumpers: left_bumper, right_bumper. Boolean.
• Buttons: a, b, x, y, dpad_up, dpad_down, dpad_left, dpad_right, start, back. Boolean.

Pushing a stick forward gives a negative Y value. Negate it when you mean forward.

double forward = -gamepad1.left_stick_y;

Structure

package org.firstinspires.ftc.teamcode;

import com.qualcomm.robotcore.eventloop.opmode.LinearOpMode;
import com.qualcomm.robotcore.eventloop.opmode.TeleOp;
import com.qualcomm.robotcore.util.ElapsedTime;

@TeleOp(name="My TeleOp", group="Linear OpMode")
public class MyTeleOp extends LinearOpMode {

    private ElapsedTime runtime = new ElapsedTime();

    @Override
    public void runOpMode() {
        // Get hardware from hardwareMap here.

        telemetry.addData("Status", "Initialized");
        telemetry.update();

        waitForStart();
        runtime.reset();

        while (opModeIsActive()) {
            // Read gamepads, set motor and servo outputs.

            telemetry.addData("Status", "Run Time: " + runtime.toString());
            telemetry.update();
        }
    }
}

This is the skeleton every SDK sample uses. ElapsedTime is how the samples show match time and how you measure timeouts.

Three parts:

1. Before waitForStart(). Get devices from hardwareMap, set directions, set servos to known positions. This runs when the driver presses Init. The robot should not move here.
2. waitForStart(). Blocks until the driver presses Start.
3. while (opModeIsActive()). The main loop. Runs until Stop is pressed or the match timer ends. All driving code goes here.

Add @TeleOp so the OpMode shows up under the TeleOp list on the Driver Station. Autonomous OpModes use @Autonomous. The SDK samples also carry @Disabled, which keeps them off the Driver Station list. Delete that line when you copy a sample into TeamCode.

Telemetry

Telemetry sends text to the Driver Station screen.

telemetry.addData("Forward Power", forward);
telemetry.addData("Slide Position", slide.getCurrentPosition());
telemetry.update();

Nothing shows until update() is called. Call it once per loop at the end. Use it to show motor powers, sensor values, and mechanism states while testing, and to show drivers things they need mid-match like wether the claw is open.

Next

Teleop Beginner builds a complete mecanum TeleOp with a slow mode. Finite State Machines in TeleOp covers mechanisms with multiple steps.