Ascension laserBIRD, Installation And Operation Manual

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laserBIRD™ Installation and Operation Guide
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OFFSET
ASCII HEX DECIMAL BINARY
Command Byte K 4B 75 01001011
Command Data X, Y, Z OFFSET DISTANCES FROM SENSOR
Normally the position outputs from the laserBIRD represent the x, y, z position of the centroid of the
sensor with respect to the origin of the Scanner. The OFFSET command allows the user to specify
a location that is offset from the centroid of the sensor. Figure 4.1 shows an application of the
offset command where the desired positional outputs from the Bird differ from the normal x, y, z
sensor outputs.
Referring to Figure 4.1, the x, y, z offset distances you supply with this command are measured in
the reference frame attached to the sensor and are measured from the sensor centroid to the
desired position. After the command is executed, all subsequent positional outputs from the Bird
will be x, y, z desired.
With the command you send to the Bird three words of data, the Xoffset, Yoffset, and Zoffset
coordinates. The scaling of these coordinates is the same as the POSITION command
coordinates. For example, assume you were using a Bird in its default maximum range mode of 36
inches full scale. Also assume the Xoffset, Yoffset, and Zoffset values where 5.4 inches, - 2.1
inches, and 1.3 inches. You would then output three integer or their hex equivalents to the Bird
equal to:
Xoffset = 4915 = 5.4 * 32768 / 36.
Yoffset = 63625 = 65536 - 1911
Zoffset = 1183