What is LiDAR, and how does it actually improve inspection data?
You’ve probably heard us talk about LiDAR a lot, often without much explanation of what it’s actually doing. In this article, I want to go into more detail on how it benefits our clients. Put simply, it’s the difference between a drone that produces footage and one that produces data you can measure and compare.
How LiDAR actually works
LiDAR stands for light detection and ranging. It works by firing out rapid pulses of laser light and measuring how long each pulse takes to bounce back. Do that thousands of times a second while the drone moves through a space, and you build up a point cloud. That’s a 3D map made of millions of separate points, and each one is a real measurement of a real surface.
Mapping without GPS: how the Elios 3 uses LiDAR
On the Elios 3, that LiDAR is tied into a SLAM-based stabilisation system. SLAM stands for simultaneous localisation and mapping. Think of a tank, vessel, or run of ductwork. These are GPS-denied spaces, so the drone has no satellite signal to tell it where it is. Instead, SLAM uses the LiDAR data itself as a positioning reference. This lets the drone hold a stable position while it builds the map. As a result, it no longer needs GPS to know where it’s going.
Why a measurable point cloud matters more than footage
The practical benefit isn’t the map on its own. It’s what you can do with it afterwards. A point cloud is measurable, so you can pull dimensions from it. You can also overlay it against a previous inspection’s point cloud to spot movement or deformation. That means we can hand a client a model they can explore. That’s very different to a video they simply have to take our word on. For asset owners tracking corrosion or structural change, that ability to compare matters more than the footage itself.
Where LiDAR delivers the most value
Here’s where this proves most useful for the clients and sectors we work with. For oil and gas and chemical processing clients, it’s storage tank and pressure vessel internals. We map wall condition and compare it against the previous shutdown’s data, without anyone entering the vessel. Power generation is a similar story. Boiler internals and stack linings are GPS-denied, high-value assets, which makes repeatable, measurable data particularly useful ahead of an outage. Water utilities benefit too, especially in reservoir roof voids and clarifier interiors. There, the same ability to compare supports the asset condition evidence that AMP8 programmes increasingly expect. So the common thread isn’t the sector — it’s the environment. Anywhere GPS doesn’t reach, and the client needs more than a visual sign-off, LiDAR earns its place.
What LiDAR doesn’t replace
It’s also worth being clear about what LiDAR doesn’t replace. It’s a mapping and measurement tool, not a defect detection method in its own right. Instead, it works alongside the visual and thermal payload, not instead of it. The real value comes from combining all three. Visual shows what’s there, thermal reveals what’s hidden, and LiDAR pinpoints exactly where it is and how it compares to last time.
If you’re evaluating drone data quality against your existing inspection records, ask your provider about LiDAR-based point cloud data. It’s the detail that matters most.
Contact Sutro Group
To find out how Sutro Group’s specialist inspection services can support your maintenance programme, contact our team:
0800 069 9395
info@sutrogroup.co.uk