Specification Sheet

WT901BLECL | Datasheet v20-0707 | http://wiki.wit-motion.com/english
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Note:
1. The coordinate system used for attitude angle settlement is the
northeast sky coordinate system. Place the module in the positive direction, as
shown in Chapter 3.3, direction forward is the X-axis, the direction left is the
Y-axis, and direction upward is the Z-axis. Euler angle represents the rotation
order of the coordinate system when the attitude is defined as Z-Y-X, that is,
first turn around the Z-axis, then turn around the Y-axis, and then turn around
the X-axis.
2. Although the range of the roll angle is ± 180 degrees, in fact, since
the coordinate rotation sequence is Z-Y-X, when expressing the attitude, the
range of the pitch angle (Y-axis) is only ± 90 degrees, and it will change to less
than 90 after exceeding 90 degrees Degrees while making the X-axis angle
greater than 180 degrees. For detailed principles, please Google Euler angle and
posture-related information.
3. Since the three axes are coupled, they will show independent changes
only at small angles, and the attitude angles will change at large angles. For
example, when the Y-axis is close to 90 degrees, even if the attitude only
rotates around the Y-axis, the angle of the axis will also change greatly, which
is an inherent problem with Euler angles indicating attitude.
Description:
1. The data is sent in hexadecimal not ASCII code.
2. Each data is transmitted in order of low byte and high byte, and the two
are combined into a signed short type data. For example, the X-axis
acceleration data Ax, where AxL is the low byte and AxH is the high byte.
The conversion method is as follows:
For example:
Assuming that Data is actual data, DataH is the high byte part, and DataL is
the low byte part, then: Data = ((short) DataH << 8) | DataL. It must be
noted here that DataH needs to be converted to a signed short data first and
then shifted, and the data type of Data is also a signed short type, so that it
can represent negative numbers.