User's Manual
Table Of Contents
- 1 Introduction
- 2 Setup
- 3 Data Structure
- 4 Web Control
- 5 PandarView
- 6 Communication Protocol
- 7 Sensor Maintenance
- 8 Troubleshooting
- Appendix I Channel Distribution
- Appendix II Absolute Time and Laser Firing Time
- Appendix III PTP Protocol
- Appendix IV Phoenix Contact
- Appendix V Nonlinear Reflectivity Mapping
- Appendix VI Certification Info
- Appendix VII Support and Contact
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Appendix II Absolute Time and Laser Firing Time
◼ Absolute Time of Point Cloud Data Packets
The absolute packing time of a Point Cloud Data Packet is the sum of UTC time and μs time.
• UTC time can be retrieved either from the current Point Cloud Data Packet (6 bytes, year, month, date, hour, minute, second), or from the previous
GPS Data Packet (6 bytes of Date and 6 bytes of time).
• μs time can be retrieved from this Point Cloud Data Packet (4 bytes)
NOTE The calculation of absolute time is different when PTP protocol is used. See Appendix III PTP Protocol.
◼ Laser Firing Time
Assuming that the absolute packing time of a Point Cloud Data Packet is t0, the end time of each block (the time when all the lasers finish firing) can be
calculated.
For Pandar40P, there are 10 blocks of ranging data in each Point Cloud Data Packet, as shown below. Each block contains the ranging data from 40
channels, one return per channel.
Table II.1 Point Could UDP Data – Ranging Data
Ranging Data: 1240 bytes (10 blocks)
Block1
Block2
Block3
…
Block10
0xFFEE
0xFFEE
0xFFEE
…
0xFFEE
Azimuth 1
Azimuth 2
Azimuth 3
…
Azimuth 10
Channel 1
Channel 1
Channel 1
…
Channel 1
Channel 2
Channel 2
Channel 2
…
Channel 2
…
…
…
…
…
Channel 40
Channel 40
Channel 40
…
Channel 40