Ascension laserBIRD, Installation And Operation Manual

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laserBIRD™ Installation and Operation Guide
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DC FILTER CONSTANT TABLE ALPHA_MIN
When PARAMETERnumber = 5 during EXAMINE, The Bird returns 7 words (14 bytes) which
define the lower end of the adaptive range that filter constant ALPHA_MIN can assume in the DC
filter as a function of sensor to Scanner separation. When ALPHA_MIN = 0 Hex, the DC filter will
provide an infinite amount of filtering (the outputs will never change even if you move the sensor).
When ALPHA_MIN = 0.99996 = 7FFF Hex, the DC filter will provide no filtering of the data.
The default values as a function of Scanner to sensor separation range are:
Std. Range
Range
ALPHA_MIN
(inches) (decimal)
0 to 17 0.02 = 028F Hex.
17 to 22 0.02
22 to 27 0.02
27 to 34 0.02
34 to 42 0.02
42 to 54 0.02
54 + 0.02
To CHANGE ALPHA_MIN, send The Bird seven words of PARAMETERdata corresponding to the
ALPHA_MIN table defined above. At the shorter ranges you may want to increase ALPHA_MIN to
obtain less lag while at longer ranges you may want to decrease ALPHA_MIN to provide more
filtering (less noise/more lag). ALPHA_MIN must always be less than ALPHA_MAX
.
DISABLE/ENABLE DATA READY OUTPUT
Enabling the DATA READY character provides a method for notifying you as soon as the newest
position and orientation data has been computed. Typically, you would issue a POINT data
request as soon as you receive the DATA READY command. If you are running in STREAM mode
you should not use the DATA READY character since the position and orientation is sent to you
automatically as soon as it is ready.
When PARAMETERnumber = 8 during EXAMINE, The Bird outputs one byte of data, equal to 1 if
Data Ready Output is enable or a 0 if disabled.
To CHANGE DATA READY, send The Bird one byte of PARAMETERdata = 1 if The Bird is to
output the Data Ready Character every measurement cycle as soon as a new measurement is
ready for output. The default Data Ready Character is a comma (2C Hex, 44 Dec).
SET DATA READY CHARACTER
When PARAMETERnumber = 9 during EXAMINE, The Bird returns one byte, the current ASCII
value of the Data Ready Character.
To CHANGE the DATA READY CHARACTER, send The Bird one byte of PARAMETERdata equal
to the character value that The Bird should use as the Data Ready Character
.