Acquisition FAQs

Acquisition: Frequently Asked Questions

Do I need to fly figure-eights before and after scanning?

Yes, ALWAYS fly figure-eights before scanning. Flying figure-eights minimizes the covariance values (uncertainty position/attitude) and allows the navigation system to better estimate the current IMU drift and noise. If you intend to post-process the trajectory for increased accuracy, you must fly another set of figure eights after the scan is complete.

How far can the GNSS base station be from the location where data will be collected?

The accuracy of corrections will degrade with distance at approximately 1 ppm as a rule of thumb. This means that for each 1 km from the GNSS reference station, there will be an expected 0.1 cm loss of accuracy. For missions that span long distances it is recommended using multiple reference stations if possible. Adding data from public stations can also be a good option.

I collected data with the wrong rover profile or incorrect configuration settings. Can this be corrected in post processing?

Yes, you can correct IMU or sensor rotation and translation values when post processing. IMU to Antenna lever arm offsets and the Body to IMU Rotations can be corrected when processing the trajectory using Inertial Explorer or in a NavLab LiDARMill pipeline. Other sensor rotations and translations/offsets for LiDAR or Cameras can be corrected in SpatialExplorer or a SpatialFuser pipeline in LiDARMill. Contact support@phoenixlidar.com if you need assistance obtaining the correct values.

I mounted the system on backwards. Can this be corrected in post processing?

Why weren’t images captured even though I activated the camera sensor in SpatialExplorer during scanning?

Most likely the Event Pin of the camera sensor in SpatialExplorer is set to “None 0”. This will cause the camera to not register any shutter events which will result in an empty .cam file. Within the Acquisition tab of the Rover Camera sensor settings, there is an option to set the Event Pin of the camera. The Event Pin option assigns an event listener to the camera sensor’s digital circuit pin. If you are only using a single camera, it is important to ensure that the Event Pin is set to “Primary 1.” Refer to SpatialExplorer’s Rover Camera Sensor Settings in CAM X for more information.

Why can’t I connect via ethernet to rover to download rover data?

Your computer does not have the correct alternate IP configuration. Field computers configured by Phoenix LiDAR Systems will default to an alternative IP configuration of 192.168.200.20 when no IP address is obtained through DHCP on the primary ethernet port within 3 minutes. This will allow a computer to establish a connection to the rover via ethernet after the DHCP acquisition times out. Refer to Wired Ethernet Network Card Setup for more information.

Why won’t SpatialExplorer connect to rover-wire or rover-wifi?

Your computer’s hosts file does not contain the correct entries to connect to rover. All Phoenix LiDAR Systems rovers are pre-configured with static IP addresses that can be reached via an ethernet (192.168.200.10) or a Wi-Fi connection (192.168.20.10). To avoid typing in the IP addresses, field computers configured by Phoenix LiDAR Systems contain individual entries in the Windows hosts file that map the ethernet and Wi-Fi IP addresses to specific names, rover-wire and rover-wifi respectively. Refer to Modify Hosts File for more information.

I updated my IMU to antenna offset values in SpatialExplorer. Why didn’t the changes immediately update on rover?

Any changes made to the rover Navigation System, i.e. changes to the IMU to antenna offset values, requires restarting the rover. Restarting SpatialExplorer is not necessary. To restart the rover with SpatialExplorer use the "Shutdown Rover" command and leave the box next to “Power off onboard computer" unchecked. To manually restart rover, utilize the CPU button on the side of the NavBox.

What is the rover’s main source of power?

The rover can obtain power through the Power Cable with Integrated Splitter from two sources: external and battery. The rover’s primary source of power is derived from the vehicle (external). The XT60 (yellow) connector from the Power Cable with Integrated Splitter connects to the vehicle’s power source, typically an XT60 female connector. Additionally, the rover can also be powered by a LiPo battery by connecting the EC5 (blue) connector on the Power Cable with Integrated Splitter to the corresponding EC5 connector on the battery. While both power sources can be connected simultaneously, we recommend only using the battery power in “hot swapping” scenarios that require the rover to remain powered on for maintenance purposes.

Do I need to connect the Wi-Fi antennas on the rover if I’m only using 3G/4G cellular service?

If you are only going to be using 3G/4G cellular service to connect to the rover, it is not necessary to connect the Wi-Fi antennas. However, it is necessary to install the Wi-Fi terminators on the Wi-Fi antenna ports. The Wi-Fi terminators attach to the Wi-Fi antenna ports and protect the Wi-Fi interface when Wi-Fi is not in use. If you don’t install the Wi-Fi terminators on the Wi-Fi antenna ports of the rover navigation box when Wi-Fi is not in use, you could destroy the Wi-Fi transmitter/receiver.

What is the recommended system maintenance/boresight frequency?

Phoenix LiDAR Systems recommends biennial (once every two years) maintenance/boresighting of each system to ensure accuracy and functional integrity.

What are the advantages of using a dual GNSS antenna system?

All IMUs suffer from 'drift' - an ever-increasing difference between where the system thinks it is located and the actual location. This constant error in acceleration results in a linear error in velocity and a quadratic error growth in position. A dual GNSS antenna setup is utilized to assist the navigation system with minimizing positional and heading error by maintaining a constant base line between the two antennas. With the two antennas at fixed distance apart, and the relationship between this baseline axis and the vehicle heading axis known, you can better correct for trajectory position and heading inaccuracies.

How can I directly access the web server of a Velodyne LiDAR sensor?

Accessing the Velodyne LiDAR sensor web server will allow you to upgrade the firmware on your Velodyne LiDAR sensor. However, be aware that changing the current configuration will most likely render the LiDAR sensor unusable for scanning.

Phoenix LiDAR Systems will not be responsible for any sensor failure as a result of a user firmware upgrade

Proceed to update the firmware at your own risk.

First connect to rover via ethernet or Wi-Fi. We highly recommend connecting to rover over ethernet for any firmware upgrades.
Open your web browser of choice and type the following into the address bar to connect to the Velodyne LiDAR sensor, “rover-wire:8080” (no quotes) if connecting over ethernet or “rover-wifi:8080” (no quotes) if connecting over Wi-Fi.
If your rover system only has a single LiDAR sensor, skip this step. Otherwise, If your system has a second LiDAR sensor, you must open a new web browser window/tab and type the following into the address bar, “rover-wire:8081” (no quotes) if connecting over ethernet or “rover-wifi:8081” (no quotes) if connecting over Wi-Fi.
Once you’ve accessed the web server home page, you can proceed to change any settings and upgrade the Velodyne LiDAR sensor firmware.

How can I view a direct livestream of information from a Velodyne LiDAR sensor?

To view a livestream of information from a Velodyne LiDAR sensor, you must connect to rover using a wired ethernet connection. In order to establish a wired connection between your computer and rover, your computer should have an IP address of 192.168.200.20. This can be set either as a static IP address or as an Alternate Configuration IP address. Refer to Wired Ethernet Network Card Setup for more information. Additionally, make sure to disable the Windows Firewall. If the Windows Firewall is active, you will not be able to view a direct livestream of information from the Velodyne LiDAR sensor.

Connect to rover via ethernet.
Open your web browser of choice and type the following into the address bar to connect to the first LiDAR sensor, “rover-wire:8080” (no quotes).
If your rover system only has a single LiDAR sensor, skip this step. Otherwise, to connect to the second LiDAR sensor, open a new web browser window/tab and type the following into the address bar, “rover-wire:8081”.
Once you’ve accessed the web server home page, change the source port from 2368 to 2369.
Launch VeloView and initiate the direct livestream of information from the Velodyne LiDAR sensor.
When you are done live streaming information from the Velodyne LiDAR sensor, navigate back to the web server home page and change the source port back from 2369 to 2368.

How can I find my Phoenix LiDAR Systems connection service License Key?

To locate the rover’s License Key, you must connect to rover over ethernet (rover-wire or 192.168.200.10) or via Wi-Fi (rover-wifi or 192.168.20.10) and navigate to Settings→ Rover. Locate the License tab and you will find the rover’s corresponding License Key.

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Last updated 2 months ago