Ascension laserBIRD, Инструкция по установке и эксплуатации

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laserBIRD™ Installation and Operation Guide
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B5 0
B4 0 if the Motor speed is valid
1 if the Motor speed is invalid
B3
0
B2
0 if data from Detector #3 is valid
1 if data from Detector #3 is invalid
B1 0 if data from Detector #2 is valid
1 if data from Detector #2 is invalid
B0 0 if data from Detector #1 is valid
1 if data from Detector #1 is invalid
When PARAMETERnumber = 128 during EXAMINE, The Bird outputs one byte of data, equal to 1
if RUN TIME STATUS is enabled or a 0 if disabled.
To CHANGE RUN TIME STATUS, send The Bird one byte of PARAMETERdata = 1 if The Bird is
to append the RUN TIME STATUS byte to each data record.
NOTE: B6 and B4 will be set to '1' during power up and following a system RESET. This is to allow
time for the system initialization and self-calibration.
PREDICTION
The laserBIRD can predict positional and angular motion from 0 to 50 mSec into the future.
Kalman Filtering and linear extrapolation are combined in a technique that forecasts the selected
coordinates and angles by the desired prediction interval.
Tracking algorithms implementing prediction are well known to have a tradeoff between longer
prediction intervals on one side, and data degradation (noise and overshoot) on the other. The
following suggestions are provided:
1. Customize the selection of predicted parameters such that the laserBIRD is only predicting
motion along or about the axis of interest. This will reduce or remove noise and overshoot
in the outputs of those coordinates and angles that do not depict motion.
2. Customize the prediction interval to balance the length of forecasting versus observed
noise and overshoot.
When PARAMETERnumber = 132 during EXAMINE, The Bird returns a two byte code that
describes the current Prediction settings. The bits in the PREDICTION bytes are coded per the
following: