Q:
Do you have a simple way to demonstrate the delta-angle function in the ADIS16488?
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A:
Try this out:
- Read each Z_DELTANG_OUT and Z_DELTANG_LOW sample into a data record, while turning it 180 degrees, using its (or the PCB's) edges to line up with a table edge or something that is relatively straight.
- Take the summation of the entire data record. Does it match close to 180 degrees? How close did you get?
Here are some key points for assuring best performance:
- Synchronize data reads with the data-ready pulse. Missed samples will eliminate the displacement estimates for the time frames that they represent.
- Correct for the initial bias in the gyroscopes, before starting this experiment. This bias will cause a linear accumulation of errors, with respect to time.
- Make sure to use all 32-bits of data in the output registers. Not all of this data is actually relevant, but using only the 16-bit register (Z_DELTANG_OUT, for example) might not provide sufficient resolution, especially when using a slow rate of rotation.
For more information on this function, check out ADIS16488A datasheet. On the present revision (Rev D), this section is located on page 15: