Ascension laserBIRD, Инструкция по установке и эксплуатации

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4: Software Operation: Tools for Successful Tracking
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POSITION
ASCII HEX DECIMAL BINARY
Command Byte V 56 86 01010110
In the POSITION mode, The Bird outputs the X, Y, and Z positional coordinates of the sensor with
respect to the Scanner. The output record is in the following format for the six transmitted bytes:
MSB LSB
7 6 5 4 3 2 1 0 BYTE #
1 X8 X7 X6 X5 X4 X3 X2 #1 LSbyte X
0 X15 X14 X13 X12 X11 X10 X9 #2 MSbyte X
0 Y8 Y7 Y6 Y5 Y4 Y3 Y2 #3 LSbyte Y
0 Y15 Y14 Y13 Y12 Y11 Y10 Y9 #4 MSbyte Y
0 Z8 Z7 Z6 Z5 Z4 Z3 Z2 #5 LSbyte Z
0 Z15 Z14 Z13 Z12 Z11 Z10 Z9 #6 MSbyte Z
The X, Y, and Z values vary between the binary equivalent of ± MAX inches. Where MAX = 36" or
72". The default positive X, Y, and Z directions are shown in
Figure 3.1
Scaling of each position coordinate is full scale = MAX inches. That is,
+MAX = 7FFF Hex, 0 = 0 Hex, -MAX = 8000 Hex. Since the maximum range (Range = square
root(X**2+Y**2+Z**2)) from the Scanner to the sensor is limited to MAX inches, only one of the X,
Y, or Z coordinates may reach its full scale value. Once a full scale value is reached, the positional
coordinates no longer reflect the correct position of the sensor.
To convert the numbers into inches first cast it into a signed integer. This will give you a
number from +/- 32767. Second multiply by 36 or 72. Finally divide the number by 32768 to get
the position
in inches. The equation should look something like this:
(signed int(Hex #) * 36) / 32768
Or: (signed int(Hex #) * 72) / 32768