API Reference

Motors

Control DC motors, smart motors, and servos with precision speed, position, and torque control.

Motor(port) Constructor

Creates a new motor object on the specified port.

Parameters

port int Motor port number (1-21)

Example

# Initialize a motor on port 1
left_motor = Motor(1)

# Initialize with reversed direction
right_motor = Motor(2, reversed=True)

spin(direction, velocity, units) Method

Spins the motor in the specified direction at the given velocity.

Parameters

`direction`	DirectionType	FORWARD or REVERSE
`velocity`	float	Speed value
`units`	VelocityUnits	PCT, RPM, or DPS

Example

# Spin motor forward at 50% speed
left_motor.spin(FORWARD, 50, PCT)

# Spin motor in reverse at 100 RPM
left_motor.spin(REVERSE, 100, RPM)

spin_to_position(position, units, velocity, wait) Method

Rotates the motor to an absolute position.

Parameters

`position`	float	Target position value
`units`	RotationUnits	DEG, REV, or RAW
`velocity`	float	Speed (default: 50)
`wait`	bool	Wait for completion (default: True)

Example

# Rotate to 90 degrees
arm_motor.spin_to_position(90, DEG)

# Rotate 2 full revolutions at 75% speed
arm_motor.spin_to_position(2, REV, 75)

stop(brake_type) Method

Stops the motor using the specified braking mode.

Parameters

brake_type BrakeType COAST, BRAKE, or HOLD

Example

# Stop and hold position
arm_motor.stop(HOLD)

# Stop and coast (no resistance)
drive_motor.stop(COAST)

Sensors

Read distance, touch, color, gyro, and other sensor values for robot awareness.

Distance(port) Constructor

Creates an ultrasonic distance sensor object.

Example

# Initialize distance sensor on port 5
front_distance = Distance(5)

# Read distance in millimeters
dist = front_distance.object_distance(MM)

# Check if object is detected
if front_distance.is_object_detected():
    print("Object found at", dist, "mm")

Gyro(port) Constructor

Creates a gyroscope sensor for rotation and heading tracking.

Example

# Initialize gyro sensor
gyro = Gyro(3)

# Calibrate before use
gyro.calibrate()

# Get current heading (0-360)
heading = gyro.heading()

# Get rotation from start
rotation = gyro.rotation()

Bumper(port) Constructor

Creates a touch/bumper sensor for collision detection.

Example

# Initialize bumper sensor
front_bumper = Bumper(7)

# Check if pressed
if front_bumper.pressing():
    drivetrain.stop()
    drivetrain.drive_for(REVERSE, 200, MM)

LineTracker(port) Constructor

Creates a line tracking sensor for following lines.

Example

# Initialize line trackers
left_line = LineTracker(1)
right_line = LineTracker(2)

# Get reflectivity (0-100)
left_val = left_line.reflectivity()

# Simple line following
while True:
    if left_line.reflectivity() > 50:
        drivetrain.turn(LEFT)
    elif right_line.reflectivity() > 50:
        drivetrain.turn(RIGHT)
    else:
        drivetrain.drive(FORWARD)

Drivetrain

High-level movement control for differential and holonomic drive systems.

Drivetrain(left_motor, right_motor, wheel_travel, track_width) Constructor

Creates a differential drivetrain from two motors or motor groups.

Example

# Create motor groups
left_motors = MotorGroup(Motor(1), Motor(2))
right_motors = MotorGroup(Motor(3, True), Motor(4, True))

# Initialize drivetrain (wheel: 319.19mm circumference, track: 320mm)
drivetrain = Drivetrain(left_motors, right_motors, 319.19, 320)

drive_for(direction, distance, units, velocity, wait) Method

Drives the robot for a specified distance.

Example

# Drive forward 500mm at 50% speed
drivetrain.drive_for(FORWARD, 500, MM, 50)

# Drive backward 12 inches
drivetrain.drive_for(REVERSE, 12, INCHES)

turn_for(direction, angle, units, velocity, wait) Method

Turns the robot by a specified angle.

Example

# Turn right 90 degrees
drivetrain.turn_for(RIGHT, 90, DEG)

# Turn left 45 degrees at 25% speed
drivetrain.turn_for(LEFT, 45, DEG, 25)

arcade(forward, turn) Method

Controls the drivetrain using arcade-style inputs.

Example

# Driver control loop
while True:
    forward = controller.axis3.position()
    turn = controller.axis1.position()
    drivetrain.arcade(forward, turn)
    wait(20, MSEC)

Vision

Computer vision APIs for object detection, color tracking, and AI recognition.

Vision(port, signatures) Constructor

Creates a vision sensor with color signatures for object detection.

Example

# Define color signatures
RED_BALL = Signature(1, 8973, 11143, 10058, -2119, -1053, -1586, 5.4, 0)
BLUE_BALL = Signature(2, -2477, -1387, -1932, 6561, 8421, 7491, 2.5, 0)

# Initialize vision sensor
vision = Vision(8, RED_BALL, BLUE_BALL)

take_snapshot(signature) Method

Captures current frame and returns detected objects matching the signature.

Example

# Take snapshot looking for red balls
vision.take_snapshot(RED_BALL)

# Check if objects found
if vision.object_count > 0:
    # Get largest object
    obj = vision.largest_object
    
    # Get object properties
    center_x = obj.centerX  # 0-316
    center_y = obj.centerY  # 0-212
    width = obj.width
    height = obj.height
    
    # Track object (center screen = 158)
    error = 158 - center_x
    drivetrain.arcade(30, error * 0.5)

AIVision(port) Constructor

Creates an AI-powered vision sensor for advanced object recognition.

Example

# Initialize AI Vision (MRX AIR platform)
ai_vision = AIVision(10)

# Detect game elements
ai_vision.take_snapshot(AI_GAME_ELEMENT)

for obj in ai_vision.objects:
    print(f"Found: {obj.label} at ({obj.centerX}, {obj.centerY})")
    print(f"Confidence: {obj.confidence}%")
    
# AprilTag detection for positioning
ai_vision.take_snapshot(AI_APRILTAG)
if ai_vision.object_count > 0:
    tag = ai_vision.largest_object
    print(f"Tag ID: {tag.id}, Distance: {tag.distance}mm")

Controller

Read joystick positions, button states, and display information on the controller screen.

Controller() Constructor

Creates a controller object for driver input.

Example

# Initialize controller
controller = Controller()

# Read joystick axes (-100 to 100)
forward = controller.axis3.position()  # Left Y
turn = controller.axis1.position()     # Right X

# Check button states
if controller.buttonA.pressing():
    intake.spin(FORWARD)
    
if controller.buttonB.pressing():
    intake.stop()

# Use button events
def on_button_r1_pressed():
    catapult.spin_for(FORWARD, 180, DEG)
    
controller.buttonR1.pressed(on_button_r1_pressed)

screen.print(text) Method

Displays text on the controller's LCD screen.

Example

# Display on controller screen
controller.screen.clear_screen()
controller.screen.set_cursor(1, 1)
controller.screen.print("Battery:", brain.battery.capacity(), "%")
controller.screen.next_row()
controller.screen.print("Temp:", left_motor.temperature(), "C")

Utilities

Timing functions, brain display, competition control, and system utilities.

wait(time, units) Function

Pauses program execution for the specified time.

Example

# Wait 1 second
wait(1, SECONDS)

# Wait 500 milliseconds
wait(500, MSEC)

# Control loop timing
while True:
    # Process inputs
    drivetrain.arcade(controller.axis3.position(), controller.axis1.position())
    wait(20, MSEC)  # 50Hz update rate

Timer() Constructor

Creates a timer for measuring elapsed time.

Example

# Create and use timer
match_timer = Timer()

# Reset timer
match_timer.reset()

# Check elapsed time
if match_timer.time(SECONDS) > 15:
    # Autonomous period over
    pass
    
# Time an operation
match_timer.reset()
drivetrain.drive_for(FORWARD, 1000, MM)
print("Drive took:", match_timer.time(MSEC), "ms")

Competition() Constructor

Handles competition state for autonomous and driver control periods.

Example

# Define autonomous routine
def autonomous():
    drivetrain.drive_for(FORWARD, 600, MM)
    drivetrain.turn_for(RIGHT, 90, DEG)
    intake.spin_for(FORWARD, 2, SECONDS)

# Define driver control
def driver_control():
    while True:
        drivetrain.arcade(
            controller.axis3.position(),
            controller.axis1.position()
        )
        wait(20, MSEC)

# Register callbacks
competition = Competition()
competition.autonomous(autonomous)
competition.driver_control(driver_control)

Motors

Parameters

Parameters

Parameters

Parameters

Sensors

Drivetrain

Vision

Controller

Utilities

Additional Resources

Tutorials

Build Instructions

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