Kauai Labs navX2-MXP, Руководство пользователя

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Guidance
Best Practices
isCalibrating() function) before using navX-sensor data.
4) If using the MXP connector, secure the navX-sensor circuit board
to the RoboRio
During operation of the robot, certain actions (for instance, driving over a bump at high speed) may cause
the navX-sensor circuit board to become dislodged from the MXP connector.
To avoid this case, when mounting the navx-sensor circuit board to the RoboRIO MXP port, be sure to
secure the navX-sensor circuit board firmly to the RoboRio via two correctly-sized screws.
5) Protect the Sensor
navX-sensors contain sensitive circuitry. The navX-sensor circuit board should be handled carefully.
An enclosure is recommended to protect the navX-sensor circuit board from excessive handling, “swarf”,
electro-static discharge (ESD) and other elements that could potentially damage navX-sensor circuitry.
The enclosure can also help prevent accidental shorts to ground which may occur on the MXP Expansion
I/O pins.
6) Plan for Catastrophic Sensor Failure
Any electronic component can fail or become disconnected accidentally. To ensure that your robot can
still function during a FRC match even if such a failure does occur, your robot software should handle
cases when communication with sensors such as the navX-sensor is disrupted.
An easy way to accomplish this is to use the “isConnected()” indication, and only use navX-sensor data
to control your robot when this is true.
Additionally, displaying whether the robot software is connected to the navX-sensor circuit board on the
driver “dashboard” can help the drivers quickly detect a connection problem.
7) Provide a “Zero Yaw” feature (for Field-Oriented Drive)
The navX-sensor gyro “yaw” angle will drift over time; the amount of drift depends upon the generation
of navX-sensor (“Generation 2” navX2-sensors drift less than “Classic” navX-Sensors) and also how
firmly the navX-Sensor is mounted to the chassis. While this does not normally impact the robot during a
FRC match, if using field-oriented drive during extended practice sessions it may be necessary to
periodically “zero” the yaw. Drivers should be provided a simple way (e.g., a joystick button) with which
to zero the yaw.
8) Avoid shorts on Expansion I/O pins
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