U S E R ’ S M A N U A L A N D
P R O G R A M M I N G G U I D E
HDL-32E
High Definition LiDAR™ Sensor
i S A F E T Y N O T I C E S
1I N T R O D U C T I O N
2 P R I N C I P L E S O F O P E R A T I O N
3 S E T U P
5U S A G E
7External GPS Time Synchronization
9
9
9
10
11
11
12
Packet Format and Status Byte for GPS Time Stamping
Time Stamping Accuracy Rates Laser Timing
Laser Firing Sequence
T R O U B L E S H O O T I N G
S E R V I C E A N D M A I N T E N A N C E S P E C I F I C A T I O N S
13 A P P E N D I X A :
Digital Sensor Recorder (DSR)
16 A P P E N D I X B :
HDL-32E Sample Data Packets
22 A P P E N D I X C :
Coordinate Calculation Algorithm Sample Code
23 A P P E N D I X D :
Calibration and Orientation
24 A P P E N D I X E :
Ethernet Transit Timing Table
caution — safety notice
Caution
To reduce the risk of electric shock and to avoid violating the warranty, do not open sensor body. Refer servicing to qualified service personnel.
The lightning flash with arrowhead symbol is intended to alert the user to the presence of uninsulated “dangerous voltage” within the product’s enclosure that may be of sufficient magnitude to constitute a risk of electric shock to persons.
The exclamation point symbol is intended to alert the user to the presence of important operating and maintenance (servicing) instructions in the literature accompanying the product.
1.Read Instructions — All safety and operating instructions should be read before the product is operated.
2.Retain Instructions — The safety and operating instructions should be retained for future reference.
3.Heed Warnings — All warnings on the product and in the operating instructions should be adhered to.
4.Follow Instructions — All operating and use instructions should be followed.
5.Servicing — The user should not attempt to service the product beyond what is described in the operating instructions. All other servicing should be referred to Velodyne.
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introduction
HDL-32E User’s Manual
Congratulations on your purchase of a Velodyne HDL32E High Definition LiDAR Sensor. This sensor provides state-of-the-art 3D imaging.
This manual describes how to set up and operate the HDL-32E, covers installation and wiring, addresses output packet construction and interpretation, along with GPS installation notes.
This manual is undergoing constant revision and improvement – check www.velodynelidar.com for updates.
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PrinciPLes of oPeration
Principles of Operation
HDL-32E User’s Manual
The HDL-32E creates 360° 3D images by using 32 laser/detector pairs whose housing rapidly spins to scan the surrounding environment. This design allows for the lasers to each fire thousands of times per second, providing a rich, 3D point cloud.
Digital signal processing and waveform analysis provide high accuracy, extended distance sensing and intensity data.
The HDL-32E uses a direct drive motor system, employing no belts or chains in the drive train, to improve reliability and reduce maintenance.
The unit provides:
•A 360° horizontal field of view (FOV)
•A 41.3° vertical FOV
•Usable returns up to 100 meters
360° Spinning LiDAR Sensor
41.3°
Valid Data Range
5 cm to 100 m
Figure 1. Overview of the LiDAR HDL32E 3D Imaging System.
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This section describes the standard set up assuming you are connecting the sensor to a standard computer or laptop and mounting the sensor on a vehicle. For other connections and mounting locations, please contact Velodyne for technical assistance.
The standard setup involves:
1.Unpacking the shipping case contents.
2.Securely mounting the sensor base to a vehicle or other scanning platform.
3.Connecting power to the sensor.
4.Connecting the sensor’s data output to the computer.
Case Contents
The shipping case contains:
•HDL-32E sensor unit with approximately 3 meter cable terminated at an interface box.
•Desktop AC/DC power adapter.
•AC cord.
•4.5 meter Ethernet cable.
•Garmin GPS-18LV GPS receiver with 5 meter cable.
•CD with:
-User manual. Check www.velodynelidar.com for updates.
-Calibration file (db.xml)
-DSR Viewer software
Mount Base
The sensor base provides mounting holes on the base. The sensor can be mounted at any angle from 0° to 360° with respect to the sensor base.
Refer to the figure below for location of the four 10-32 threaded, 3/8” deep mounting holes.
73.1
2.876
144.2
5.68 OVERALL HEIGHT
51.6
2.033
TWO 
.156 LOCATING FEATURES
FOR 5.32” DOWELL PINS
FOUR 10-32 THREADED MOUNTING HOLES
3/8” DEEP
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51.6 |
INTERFACE CABLE |
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85.3 |
3 METERS LONG |
||
2.033 |
|||
3.36 |
|
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Figure 2: Sensor Base Mounting
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Connect Power and Computer
The sensor units are commonly used in vehicle applications where standard 12 volt, 2 amp power is readily available.
1.Connect the interface module to power.
2.Connect the Ethernet connector to a standard PC or laptop RJ45 Ethernet port.
Operate
Before operating the sensor, make sure that:
•the sensor is in acceptable environmental conditions
•the sensor is securely mounted
Weather
The unit is weatherproofed to withstand wind, rain and other adverse weather conditions. The unit’s spinning motion helps it shed excess water from the front window that could hamper performance. Refer to the specifications page for operational and storage temperature ranges.
Shock and Vibration
Be sure the unit is mounted securely to withstand vibration and shock without risk of detachment. The unit does not need shock proofing. The unit is designed to withstand standard automotive G-forces; (500 m/sec2 amplitude, 11 msec duration shock and 3 Grms 5 Hz to 2000 Hz vibration).
Wiring
The HDL32E comes with an integral cable that is terminated at an interface box. The cable is approximately 3 meters (10’) in length. The interface box provides jacks for Ethernet, power and GPS.
Power. The 2.1 mm barrel plug jack fits the AC/DC power adapter included. The center pin is positive polarity.
note: The HDL32E does not have a power switch. It spins and operates whenever power is applied.
Ethernet. This standard Ethernet connector is designed to connect to a standard PC.
note: The HDL-32E is only compatible with network cards that have either MDI or AUTO MDIX capability.
GPS. The GPS connector fits the GPS receiver included. If you wish to wire your own GPS receiver, refer to the labeled connector within the interface box.
Cable. The cable is permanently attached at the sensor but the interface box may be removed for direct wiring and/or inserting in-line connector(s).
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The HDL-32E sensor needs no configuration, calibration, or other setup to begin producing usable data. Once the unit is mounted and wired, supplying it power will cause it to start scanning and producing data packets. The quickest way to watch the HDL-32E in action is to use Digital Sensor Recorder (DSR), the viewer software included with the unit. DSR reads in the packets from the HDL-32E over Ethernet, performs the necessary calculations to determine point locations, then plots the points in 3D on the viewer’s PC. If you have never used the HDL-32E before, this is the recommended starting point. For more on installing and using DSR, see Appendix A. You can observe both distance and intensity data through DSR.
Most users, however, will elect to create their own application-specific point cloud tracking and plotting and/or storage scheme. There are several fundamental steps to this process:
1.Establish communication with the HDL32E
2.Create a calibration table from the included db.xml data file
3.Parse the packets for rotation, distance and intensity data
4.Apply the calibration factors to the data
5.Plot or store the data as needed
Each of these steps is described in detail, below.
1.Establish communication with the HDL32E. The HDL-32E outputs two separate broadcast UDP packets. By using a network monitoring tool such as Wireshark you can capture and observe the packets as they are generated by the unit.
HDL-32 MAC ID and IP address format:
Mac ID
Each HDL-32E has a unique MAC address based on the serial number, with the last four hex digits mapping to the serial number of the unit. The following MAC ID shows serial number 4452:
60 76 88 20 11 64
IP Address
The Source IP address for the HDL-32E units maps to the last four digits in the Mac ID (and hence the serial number). In the above example, the Source IP address would be represented by IP address:
192.168.17.100
In this example, the 11 and 64 are shown as decimal numbers for the purposes of expressing the IP address.
For all HDL-32E units, the destination IP address remains fixed at 192.168.3.255.
2.Create an internal calibration table from the included db.xml data file. This table must be built and stored internal to the point-cloud processing software.
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Alternatively, the calibration data can be found in the included db.xml file found on the CD included with the HDL32E. The calibration data for vertCorrection is the vertical correction angle for each laser, as viewed from the back of the unit and stated in degrees. Positive values have the laser pointing up and negative values have the laser pointing down.
The calibration table, once assembled, will contain 64 instances of the calibration values to interpret the packet data to calculate each point’s position in 3D space. Use only the top 32 instances.
3.Parse the packets for rotation, distance and intensity data. Each HDL32E packet has a 1206 byte payload consisting of 12 100 byte records and then a 6 byte data area that contains GPS time stamping. The zero degree position is 90 degrees to the right of the interface cable when looking at the bottom.
Each 100 byte record contains first a start identifier, then a two byte rotational value, followed by 32 3-byte combinations that report on each laser fired. Two bytes report distance to the nearest .2 cm, and the remaining byte reports intensity on a scale of 0 - 255. There are 12 100 byte records. For more on packet construction, see Appendix B.
4.Apply the calibration factors to the data. Each of the HDL32E’s lasers is fixed with respect to vertical angle. For each data point issued by the sensor, vertical correction factors must be applied to determine the point’s location in 3 Dspace referred to by the return.
note: The minimum return distance for the HDL32E is approximately 5 cm. Ignore returns closer than this.
note: There is a file on the CD called “HDL Source Example” that shows the calculations using the above correction factors. This is the code used in DSR to determine 3D locations of HDL32E data points.
5.Plot or store the data as needed. For DSR, the point cloud data, once determined, is plotted onscreen. The source to do this can be found on the CD and is entitled “HDL Plotting Example.” DSR uses OpenGL to do its plotting.
You may also want to store the data. If so, it may be useful to timestamp the data so it can be referenced and coordinated with other sensor data later. The HDL32E has the capability to synchronize its data with GPS precision time.
note: There are no user service or maintenance procedures for the Velodyne HDL32E. Velodyne does offer a preventative maintenance service for a fee. For service or maintenance, please contact Velodyne at +1 (408) 465 -2800, or log on to our website at www.velodynelidar.com.
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