Chapter 9 •
Sensor Data
This chapter provides detailed information about sensor data characteristics.
9.1 Sensor Origin and Frame of Reference
53
9.2 Calculating X,Y,Z Coordinates from Collected Spherical Data
53
9.3 Packet Types and Definitions
54
9.3.1 Definitions
54
9.3.2 Data Packet Structure
56
9.3.3 Position Packet Structure
59
9.4 Discreet Point Timing Calculation
62
9.5 Precision Azimuth Calculation
66
9.6 Converting PCAP Files to Point Cloud Formats
69
9.1 Sensor Origin and Frame of Reference
The sensor reports distances relative to itself in spherical coordinates (radius r, elevation ω, azimuth α).
Sensor data origin (0,0,0) is 37.34 mm above the sensor base, on the center axis, as shown in
Figure 9-1 on the next page
(see the side and top views), which also shows the sensor’s frame of reference. See also
VLP-32C Mechanical Drawing
on page 104
.
9.2 Calculating X,Y,Z Coordinates from Collected Spherical Data
A computation is necessary to convert the spherical data (radius r, elevation ω, azimuth α) from the sensor to Cartesian
coordinates.
Figure 9-1 on the next page
lists the formulas for converting spherical coordinates (R, ω, α) to Cartesian
coordinates (X, Y, Z).
Chapter 9 • Sensor Data
53
