As technology improves and becomes more accessible, more use cases come to the fore. This can particularly be seen with the emergence of LiDAR.
As far back as 1960, LiDAR technology had its roots firmly planted in the aerospace technology industry. Fast-forward to 2023 and LiDAR sensors are used across a multitude of industries and for a wide range of applications.
Many of the applications we see LiDAR being used for today however, wouldn’t be possible, were it not for its ability to synchronize with GNSS and Inertial Measurement Unit (IMU) technologies. In fact, it was the emergence of these technologies in the 1980s that enabled scientists to really extract the benefits from LiDAR.
A LiDAR sensor is able to build up a picture of its surroundings, but it has no intrinsic knowledge of where in the world it is, or where it’s heading. GNSS and IMU technology can, when paired with a LiDAR sensor, provide it with this information. The GNSS receiver will tell the LiDAR where in the world it is, while the IMU will give it an understanding of its heading and pitch, and roll.
An Inertial Navigation System (INS) takes things one step further by using position updates from a GNSS receiver to aid the inertial measurements created by an IMU. When paired, the INS is able to output cm-level accurate position. When the navigation measurements from the INS are subsequently paired with the data from a LiDAR sensor, all of the information together enables the creation of a pointcloud.
Over the past several years, surveyors and test engineers across the world have begun to use LiDAR to help them understand their environment better. Capturing data linked to a specific location, with a high degree of accuracy, enables users to visualize, analyze and subsequently make better, more well-informed decisions about their surroundings.
However, simply pairing (georeferencing) LiDAR sensor data with the navigation measurements from an INS isn’t always enough to create a pointcloud accurate enough to service many industries.
There are many other factors to consider. One of these being boresight calibration. To survey an environment using LiDAR, an autonomous vehicle developer, or survey and mapping professional, need to first build a payload. Once created, its vitally important that the coordinate frames of the INS and LiDAR are measured accurately in respect to one another. If not, then the final pointcloud could be susceptible to blurring and double-vision, making the final result unusable.
Traditionally these angles have been measured using CAD models or even by eye. Creating a CAD model of your payload can be time-consuming, especially if you need to create more than one, or you regularly repurpose your sensors, whilst measuring coordinate frames by eye is particularly difficult to do accurately.
Overcoming the challenge
To overcome this challenge, a new way of working is necessary. Using their calibration expertise, Oxford Technical Solutions (OxTS), an INS manufacturer based in the UK, has developed a solution that can increase the accuracy of a pointcloud using the sensors already in use on a payload.
The data-driven method can be completed in a matter of minutes and can utilize the measurements from whichever sensor combination is present on your payload.
It requires the user to conduct a short survey of two retro-reflective targets, and using a ‘drag and drop’ method, upload the relevant navigation (.csv) and LiDAR (.pcap) data files to the OxTS Georeferencer software. Once uploaded, and further to a few simple steps, all that is required is for the user to click the ‘run boresight calibration’ button and the new measurements will be presented.
Once the boresight calibration has taken place, the measurements can be input prior to the georeferencing phase to ensure blurring and double-vision is kept to a minimum.
Using the new anyNAV feature, LiDAR users can georeference and boresight their payloads using whichever navigation data they choose.
OxTS Georeferencer at Geo Week
OxTS Georeferencer recently won the ‘pitch the press’ award at Geo Week where the judges commented…
“OxTS introduced their OxTS Georeferencer tool, a game-changing LiDAR georeferencing tool simplifying incredibly complex technology to a truly impressive level. This software tool enables surveyors to quickly and effectively boresight their payload, and georeference their LiDAR sensor data, allowing professionals to produce accurate pointclouds in just minutes. Judges were particularly blown away by how simple this ‘absolutely essential’ process has been made, with the presentation indicating that just a quick tutorial video and a simple click of a button produces the results a surveyor is seeking.”
– GEO Week ‘pitch the press’ judging panel
Readers of GPSWorld can request a free 14-day trial of OxTS Georeferencer here to test the concept for themselves.
All photos: OxTS
This page was produced by North Coast Media’s content marketing staff in collaboration with OxTS. NCM Content Marketing connects marketers to audiences and delivers industry trends, business tips and product information. The GPS World editorial staff did not create this content.