The origins of photogrammetry and 3D mapping can be traced back to 1480 when Leonardo da Vinci developed the concept of perspective and projective geometry. Techniques have come a long way since then, with both the technology and software becoming more accessible and affordable.
Our Emergency Services have been some of the earliest adopters of 3D mapping techniques and are leading the way when it comes to documenting our world in 3D to improve our safety and security.
The Need for Speed
3D mapping has become a valuable tool for collision investigators. Up until recently, specially trained police officers would use terrestrial laser scanners (TLS) to create a 3D representation or point cloud of the scene of an accident. This allows for retrospective analysis of a situation to investigate the cause and impact of a collision as well as providing enhanced information to support witness statements and manual measurements, ensuring that evidence is as accurate as possible for future court proceedings.
The downside to TLS is that it requires multiple set-ups to cover a large area and equipment is often large and bulky. Advancements in laser scanning technology have now seen systems shrink in size and weight, meaning that the latest mobile systems can be worn on a backpack, secured to a vehicle and now even mounted to a drone. Traffic accident response teams always try to minimise any disruption to other road users, even after the worst of accidents, so having the ability to capture data quickly and remotely can make all the difference after a major, or minor incident.
Mobile 3D mapping systems also enhance safety for those on the front line. Even after a road re-opens, it can often be necessary for collision Investigators to get up-close and personal with fast-moving traffic. 3D mapping means that measurements only need be taken once, mobile mapping systems, including UAV systems, mean that you can now take them from a safe distance.
The scope of data collected through 3D mapping techniques is huge. Outside of providing law enforcement and courts with evidence, the same data can and has been used by traffic management officials and vehicle manufacturers to map and model the effects of collisions, allowing for simulations to be carried out to improve road and vehicle safety.
Failing to Prepare….
Unfortunately, it’s often after disaster strikes that authorities seek to understand the nature of what caused the issue in the first place, yet 3D mapping can now be used to help pre-warn of impending trouble, such as in the case of the landslide at Bingham Canyon Mine in 2013. This was one of the largest non-volcanic landslide events in the history of North America. Using InSAR (Interferometric Synthetic Aperture Radar) to create 3D maps, mine operator Rio Tinto could pre-warn workers of a change in stability of one of the mine’s faces. When nearly 100 million cubic metres of debris collapsed into the mine, all personal and valuable equipment had been evacuated.
Similar technology can now be mounted to a drone. UAV based imaging radar has great potential for emergency mapping applications thanks to its ability to function in all weather conditions. Radar waves can penetrate cloud cover and dust to allow for clear images to be created even in the most difficult environments, meaning that intelligence can be gathered when it matters most. Given the shrinking size of most sensors and increasing payload capacity of many drones, it is now possible to combine the two technologies of unmanned flight and radar for great effect.
Another remote sensing technique being used to help create disaster management, and prevention strategies is LiDAR. Both TLS and MLS (Mobile Laser Scanning) systems have been used to great effect in the aftermath of some of the world’s most recent, and devastating, natural disasters.
Hurricane Katrina hit New Orleans in August 2005, causing nearly 2000 deaths. 3D maps of the city, both before and after the event were used to help emergency services to identify the worst hit areas and mobilize rescue teams quickly. When the waters subsided, LiDAR maps were again used in the creation of the Hurricane and Storm Damage Risk Reduction System (HSDRRS) – a 133 mile perimeter which would protect the city from future surges.
It’s not just the United States who have benefitted from using 3D mapping for more effective pre-planning. In the wake of Hurricane Desmond, the University of Salford deployed a drone which enabled them to immediately capture data showing where flood waters were likely to flow and finally disperse, providing an early warning that waters would flood the city of Carlisle.
The UK’s Environment Agency have also been using 3D mapping technology to create flood models and asses coastal change for many years. Techniques have varied over time – from photogrammetry derived digital terrain models, to point clouds from an airborne laser scanner – all data collected has helped the UK to develop more intelligent and accessible flood risk models, enabling emergency services to plan for future events.
The Calm After the Storm
3D mapping doesn’t only help authorities to plan and execute a disaster management strategy, it can also be invaluable when assessing damage and changes to critical infrastructure after an event. When the devastating earthquakes hit central and southern Italy in 2016, firefighters and search and rescue teams deployed drones to examine the wrecked towns and villages for signs of life, leading to enhanced rescue efforts being carried out. Across the two earthquakes, hundreds of communities were displaced, but life must go on. It became critical for researchers to capture and document the sites for posterity and retrospective analysis before clean-up operations began.
A team from the Brigham Young University and the Geotechnical Extreme Events Reconnaissance Association (GEER) visited Italy armed with a drone and camera. Over 50 gigabytes of high-res photographs were collected which were then used to create 3D interactive models of the worst hit areas. The UAV platform allowed researchers to view areas which had been rendered impassable or too unstable for crews to access. The photogrammetry software used has allowed researchers and civil engineers to catalogue the destruction and prioritise repairs, as well as understand more about how such events affect ancient and modern infrastructure.
Crime & Punishment
Whether using photogrammetric techniques, or LiDAR derived point cloud data, the benefits of three-dimensional georeferenced datasets are immeasurable when used for emergency response. The same can be said for crime scenes, especially when using a UAV to collect the data – combine the advantages of an unobstructed aerial perspective with the ability to create 2D and 3D maps with millimetre level accuracy and you have one of the most powerful weapons in the forensic investigator’s arsenal.
Credit: Advanced Laser Imaging
Once processed, the three-dimensional representations can replace crime-scene sketches. The 3D model can be viewed from any perspective and allow investigators to identify and tag evidence to specific locations. This allows for retrospective analysis to corroborate witness statements and confirm theories as to how events played out. Invaluable at the investigation stage and significantly influential when a case goes to court – an impartial and accurate aerial view of the scene available moments after it happened.
The first force in the UK to trial and approve the use of drones for crime prevention and forensic investigations is Devon & Cornwall Police. Starting with four DJI Inspire drones, the force took over a year to evaluate the benefits of UAV technology for fighting domestic crime. Their fleet now has now grown to 6 units, including the Mavic Pro, with aims for 40 officers to complete their CAA training in the next 12 months. The head of the newly created unit, Chief Superintendent Jim Nye said, “Drones will aid officers as part of missing person searches, crime scene photography, responding to major road traffic accidents, coastal and woodland searches and to combat wildlife crime”. The force’s drones are also fitted with thermal cameras to allow operations to be conducted day and night.
Unmanned Aerial Vehicles are one of the most important advancements for emergency planning and management. The ability to obtain an aerial view of an incident without the time and expense of deploying a helicopter is rapidly being exploited by first response teams across the world. Drones, when combined with the correct payload systems, provide a new level of operational remote sensing to allow enhanced pre-planning, response and even rescue.
All of the 3D mapping use-cases mentioned in this blog could now potentially be driven by drones. With UAV based LiDAR and Radar systems now available and cutting-edge photogrammetry software becoming widely accessible, drones are now at the leading edge when it comes to creating 3D maps. From enhanced intelligence following a serious incident to improving safety for front-line officers – 3D mapping via UAVs will be a game-changer for us all when devastating incidents occur.
Specialists in Drones for Emergency Response:
COPTRZ are committed to providing the best professional development opportunities for many industries, including Law Enforcement and Forensic teams. We are now offering an expert course on Using Drones for Incident & Forensic Imaging. Covering photography, 3D mapping and modelling and thermal imaging, this course is a must for qualified drone pilots working in the emergency services field who are looking to complete drone based imaging missions with confidence.
Want to find out more about drones suitable for emergency response? Contact us or call 0330 111 7177
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