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Unread 24-02-2015, 11:44
slibert slibert is offline
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Re: ANNOUNCING: navX MXP Robotics Navigation Sensor

Quote:
Originally Posted by randantor View Post
What are the units for the raw gyro output in the LabVIEW Library? It looks like it could be radians/second but I'm not entirely sure.
Raw Gyro data is a 16-bit signed value, in hardware units. Conversion to a real-world value requires knowledge of the sensor Full Scale Range (FSR).

The Gyro FSR is configured for 2000 deg/sec. To convert raw gyro data to deg/sec, simply divide the raw gyro value by 2000:

float curr_deg_sec_x = (float)raw_gyro_x / 2000.0;

Note that gyro values are calibrated, so have had offsets automatically applied to them by the Digital Motion Processor (DMP) on the Invensense MPU-9250 silicon.

[Raw acceleration data is similar; in this case, in units of Gs and since the Accelerometer FSR is configured for +/- 2G, the calculation is:

float curr_accel_x = (float)raw_accel_x / 2.0;]

Most users don't access the raw gyro data directly, since to be useful it typically requires the user software to integrate the data - and for typical use cases, this work is offloaded to the navX MXP processor.

Last edited by slibert : 24-02-2015 at 12:46.
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