TEXAS TORQUE

Torque Learn

A Rookie's Guide to Texas Torque

navX

The navX is an integrated accelerometer, gyroscope, and magnetometer that allows tracking the position of the robot.

navX

Board

The board is located on the kMXP port on the RoboRIO, which is the large one in the center.

The navX has two on-board buttons, calibrate (CAL) and reset (RESET). Holding down reset for three seconds and waiting for the orange light to turn on and off will zero the gyro. Holding down CAL for 10 seconds and then pressing the reset button will recalibrate the sensors.

Code

We use the AHRS class for interfacing with the navX. The gyro can be instantiated with:

AHRS gyro = new AHRS(SPI.Port.kMXP);

Below is a list of common methods:

double pitch = gyro.getPitch(); // Get the pitch
double yaw = gyro.getYaw(); // Get the yaw
double roll = gyro.getRoll(); // Get the roll

gyro.reset(); // Zero the gyro

gyro.getFusedHeading() // Get a more accurate yaw, [0,360]

See the section Fused Heading for more in-depth details on the difference in headings.

Magnetometer

The magnetmeter on the NavX informs the NavX of the Earth’s gravitational field. It must be calibrated using this software.

Unplug the NavX from the SPI port, and plug the NavX with a mini-B to a computer running the software. Align the NavX according to the included pictures (12 data points). Flash to the controller once done.

Problems & Solutions