Nav X only resetting about 1-2 seconds after enabling

EmilTheMeal · February 18, 2024, 10:32am

We tried to reset the nav x gyro to 0 in the swerve constructor, but it wasn’t being called. We thought that the gyro might be calibrating and that’s why we couldn’t set the value. So we tried doing it in periodic when it stops calibrating and is connected to the robot (only once obviously), and it works fine and resets after 1-2 seconds. Is this normal? Is there a way to circumvent this and have it reset immediately?

j.e · February 18, 2024, 10:03pm

I think you’re describing a problem we worked around.

github.com

TeraViks/Thor_2023/blob/main/src/main/java/frc/robot/subsystems/DriveSubsystem.java#L119


      
                DriveConstants.stateStdDeviations,
                DriveConstants.visionStdDeviations);
          
          // private final Field2d m_field = new Field2d();
          
          /** Creates a new DriveSubsystem. */
          public DriveSubsystem(CameraSubsystem cameraSystem) {
            m_cameraSystem = cameraSystem;
            m_gyro.enableBoardlevelYawReset(true);
            // We have to wait for the gyro to callibrate before we can reset the gyro
            while (m_gyro.isCalibrating()) {Thread.yield();}
            zeroGyro();
          
            AutoBuilder.configureHolonomic(
                this::getPose, // Robot pose supplier
                this::initOdometry, // Method to reset odometry (will be called if your auto has a starting pose)
                this::getSpeeds, // ChassisSpeeds supplier. MUST BE ROBOT RELATIVE
                this::driveRobotRelative, // Method that will drive the robot given ROBOT RELATIVE ChassisSpeeds
                new HolonomicPathFollowerConfig( // HolonomicPathFollowerConfig, this should likely live in your Constants class
                    new PIDConstants(5.0, 0.0, 0.0), // Translation PID constants
                    new PIDConstants(5.0, 0.0, 0.0), // Rotation PID constants

EmilTheMeal · February 19, 2024, 8:20am

We ended up doing something like this, and it works. Your solution seems cleaner, so I’ll try it out!

Thank you

Joe_Ross · February 19, 2024, 4:59pm

Even if you wait until the NavX has finished calibrating, it doesn’t zero immediately, as it sends a command to the NavX Firmware to zero, and it takes time for the NavX to zero and send the result back. But it should be on the order of 10s of ms, not 1-2 seconds, IIRC.

bovlb · February 19, 2024, 10:17pm

It sounds like you’ve solved your problem, but my general advice would be not to reset the hardware gyro, but instead rely on features like Odometry.resetPosition, which says:

Resets the robot’s position on the field.
The gyroscope angle does not need to be reset here on the user’s robot code. The library automatically takes care of offsetting the gyro angle.

system · February 18, 2025, 10:18pm

This topic was automatically closed 365 days after the last reply. New replies are no longer allowed.