KOP Gyro steadily decreasing

[brennonbrimhall]

Thanks for the responses, guys.

Originally Posted by Team3266Spencer

Reset the gyro as often as possible in the code.

Originally Posted by MagiChau

I agree with resetting the gyro as much as possible.

As in every cycle of test/auto/teleopPeriodic()? I thought that resetting set your current point as the new reference frame.

By the way, MagiChau, thanks for the whitepaper. It is exceptionally informative.

Originally Posted by Greg McKaskle

As mentioned, gyros are not perfect or magic. They are a sensor circuit and are affected by a number of real-world issues such as electrical noise, temperature, and operating procedures.

I understand. My concern was that the drift was exceptionally steady, which I assumed meant a problem outside of the sensor.

[Ether]

Originally Posted by brennonbrimhall

I thought that resetting set your current point as the new reference frame.

Yes. So you set the current point as your new reference... when the current point is your desired zero.

[brennonbrimhall]

Originally Posted by Ether

Yes. So you set the current point as your new reference... when the current point is your desired zero.

Hence my confusion. To reset every iteration of testPeriodic(), autoPeriodic(), or teleopPeriodic() would reset my current frame of reference every 20ms. When would you suggest resetting the gyro, so that the drift is minimized, but the reference is functionally unchanged?

[Ether]

Originally Posted by brennonbrimhall

Hence my confusion. To reset every iteration of testPeriodic(), autoPeriodic(), or teleopPeriodic() would reset my current frame of reference every 20ms.

Spencer said to reset it "as often as possible", not every 20ms.

When would you suggest resetting the gyro, so that the drift is minimized, but the reference is functionally unchanged?

It depends on the application. For example, if you're using it to measure the heading of the robot, you could have a reset button on the joystick that the driver could push whenever the robot is pointing straight downfield.

[brennonbrimhall]

Originally Posted by Ether

For example, if you're using it to measure the heading of the robot, you could have a reset button on the joystick that the driver could push whenever the robot is pointing straight downfield.

Thanks for the suggestions. Ether, for the purposes of autonomous driving, would you just ignore the sensor drift because of the short time span?

[Ether]

Originally Posted by brennonbrimhall

for the purposes of autonomous driving, would you just ignore the sensor drift because of the short time span?

Most likely. If you have access to more than one gyro, you could test them and pick the one with the least drift.

[brennonbrimhall]

Thanks for all the help!

[Ether]

Originally Posted by brennonbrimhall

By the way, MagiChau, thanks for the whitepaper. It is exceptionally informative.

Be aware that the paper was written years before the introduction of the cRIO and its FPGA. The FPGA handles all the integration of the yaw rate signal from the gyro. You don't have to write all that code shown in the paper.