Mapping the future: unveiling the M25 through innovative data visualisation

At Sensat, we obsess over capturing, processing and visualising large and diverse geospatial datasets enabling our clients to mine all the value from their data without creating slow and complex environments.

Our latest project involved mapping one of the world's most complex and extensive assets—the M25 motorway—using our state-of-the-art Leica Pegasus TRK mobile mapping unit. With around 250,000 vehicles traversing this busy motorway daily, capturing clean, usable data presents a unique challenge, particularly regarding data visualisation.

The Noise Challenge

The M25 is the busiest motorway in the UK, and the sheer volume of traffic generates significant vehicle noise that can clutter our raw LiDAR point cloud data. This noise often leads to messy datasets that hinder effective visualisation. To combat this, we employ a multipass capture strategy, driving two lanes on each side of the motorway. This approach results in four individual data tracks for every section of the road, ensuring comprehensive coverage across the wide surface, which can have up to eight lanes.

By capturing more detailed data, we can utilise advanced noise-reduction techniques that enhance the quality of our visuals.

Our Processing Workflow: Linking for Accuracy

Once we've captured the data, our processing workflow, powered by Pegasus Office software, comes into play. This workflow creates automatic and manual links between individual tracks, minimising potential errors. Doing so achieves great relative accuracy, making our visualisations appear seamless—almost as if captured in a single pass.

Incorporating ground control points further enhances the absolute accuracy of our dataset, setting the stage for high-quality visual insights.

The Post-Processing Phase: Noise Removal

The post-processing phase is where the real magic happens. Using both Pegasus Office and TerraSolid software, we run sophisticated algorithms to classify and remove noise from our data. This process identifies moving objects, such as vehicles, and distinguishes them from static features, ensuring our visualisations remain clear and focused.

The benefit of having multiple tracks along the motorway is significant; it allows algorithms to identify which data points are unique to a single track, enabling us to classify and eliminate these transient elements effectively. This results in cleaner data and more precise visualisations of the M25's infrastructure.

Addressing Obstacles: Overcoming Shadowing

Large vehicles like lorries can obstruct our mapping efforts, creating gaps in the data. However, our multipass strategy ensures that at least one of our tracks captures clear road sections. By classifying and removing these obstructions, we maintain a comprehensive dataset, enhancing the overall quality of our visual representations.

Transformative Results for Data Visualisation

The culmination of our meticulous alignment and noise removal processes results in data where none of the 250,000 vehicles appear to have ever been on the road.

. This pristine dataset allows for detailed visual inspections of the motorway, free from clutter and interference.

When visualised, the data reveals the road surface in stunning detail, enabling the inspection of assets such as lamp posts, bridges, road markings, and the road surface itself. This level of clarity is invaluable, allowing stakeholders to identify issues, defects, or cracks that may require attention—all without the need for costly road closures or risks to personnel.

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Empowering Insights Through Visualisation

At Sensat, our innovative approach to mobile mapping not only enhances data quality but also transforms how physical assets are visualised and understood. By leveraging high point densities achieved through our TRK LiDAR mobile mapping unit, we empower our customers to gain deeper insights into their assets, ultimately driving better decision-making.

In conclusion, our commitment to capturing and visualising highly accurate detailed data to enhance understanding and enable effective asset management distinguishes us in the industry.

We invite you to explore the possibilities that come with clear, actionable visual insights—transforming complex data into valuable knowledge at Sensat.