roads, targeting major routes and landmarks such as the Global Vil - lage festival and amusement park, the Old Souk markets, and Dubai’s downtown. The aim was to capture every existing feature on and along the road to create 360-degree street views, point clouds, and 2D and 3D base maps of the 60- by 60-kilometer Emirate. To provide geospatial referencing to the MX9 system, the Dubai Mu - nicipality Survey Department has a network of roughly 12,000 existing ground control points (GCPs) to provide centimeter-accuracy control for the mobile mapping. The department also has a network of Virtual Reference Stations (VRSs) to support RINEX post-processing for the MX9’s GNSS. With the MX9 mounted on top of their SUV, a two-person crew drove the roadway in two directions. Traveling at 80 kilometers/hour, the system scanned road furniture such as road signs, light poles, stop lights, markings and medians––any feature within 400 meters of the road––and captured nine images (panoramic and multi-angle) every 5 seconds. Simultaneous to the image capture, the system collected a point cloud of the AOI at 2 million points per second. On average, it took the team two to three hours to acquire 100 kilometers of data per day on both sides of the roads. “A notable benefit of the MX9 is not only that it has two scanners, but also their positioning angle, which allows us to capture features that could potentially be blocked if we only had one scanner,” says El Mustafa. “Dubai, for example, has heavy traffic, so it would be easy to miss a feature because a car passes you. Two scanners ensure that if one is momentarily blocked, the other will scan those points. In ad - dition, the MX9’s overhead reach is up to 400 meters high, so we can capture nearly all of Dubai’s tallest buildings to create an accurate and true 3D model of the city.” The GIS Center completed its first project phase of capturing all of Dubai’s major roadways, landmarks and buildings in 3D in April 2020. For the remainder of 2020, teams were focusing on collecting the rest of the road network, landscapes, and infrastructure to complete the 3D mapping of the entire emirate. “We wouldn’t have been able to finish this major achievement this quickly without the MX9,” says El Mustafa. “A surveyor using con - ventional technology would likely need nearly two months to cover the same amount of distance we collect in one day. And they’ll maybe acquire about 200 points a day. We get 360-degree panoramas every five seconds and two million 3D points per second of everything that’s there. There’s no comparison.” No Need To Explain After each data acquisition, a team used a suite of Trimble software tools to process the data. When the MX9’s GNSS and inertial data were processed with POSPac, Trimble Business Center software integrated the trajectory information and control-point measurements to georefer - ence the data collected from the MX9 cameras and scanners. They also processed and colorized each point cloud. And from the 3D view, they extracted a host of features such as road furniture, signs, houses, and building outlines to produce vectorized maps for GIS-based analyses.
The street view, panoramic images, point clouds, and base maps then were published to the GIS Center’s GeoDubai advanced geospatial portal, giving public and private end users the ability to view, measure and study any feature or structure in the city. And at the end of June 2020, the 3D mobile mapping data was integrated with the GIS Cen - ter’s latest smart innovation: Dubai Here, a Web browser system that offers access to geospatial data, including maps of Dubai’s landmarks, commercial and residential structures, parks, trees, bridges, tunnels, and transit network. “What makes the mobile mapping data so effective is that no explana - tion is needed,” says El Mustafa. “Unlike with a singular GNSS survey point, with the MX9 street views, users can see the whole city in front of them, not just a point or polygon. A photo gives 1,000 explanations. And that makes it so much easier to use.” In addition to providing precise panorama and measurable 3D views of the city, the GIS Center is also capturing and mapping the interiors of commercial and public buildings to bring that same 3D view and analysis inside. Using the Trimble Indoor Mobile Mapping Solution (TIMMS), the cart-mounted lidar and camera systems scan and image every room and object in an interior space—including desks, chairs, stairs, doors, plants, sprinklers, and vents—and provide real-world positions of each area of the building and its contents. Integrating the MX9 data with the internal TIMMS data will not only offer end users a holistic view of Dubai’s buildings and landmarks, it will provide the foundation to ultimately create the city’s Digital Twin, a complete 3D model of the whole city. That model, enhanced with Internet of Things technologies and linked to real-time information, will provide the essential information for planning and managing the city and providing effective, smart services. “Data-rich images and 3D maps give decision makers precise, up- to-date and dynamic information to support and effectively manage our core city functions,” says Almheiri. “For example, in emergency response, civil defense can immediately know the height, accessibility and complexity of a burning building’s shape, giving them the knowl - edge to plan the most effective response. Planners can use 3D maps to monitor and assess building ages and develop effective demolition strategies. Engineers can develop road design or maintenance in 3D. This is the kind of data depth and innovation we need for Dubai’s future Digital Twin and, most importantly, to build the smartest and happiest city.” And in the end, that’s what it’s all about for Dubai: being smart and happy. It may have a penchant for creating a city of “ests”–tallest, largest, fastest, easiest, cleanest–but the most important “est” for the Dubai government is being the smartest and happiest city. And that’s no laughing matter.
MARY JOWAGNER is a Freelance Writer, Editor, and Media Consultant based in Vancouver, BC. She can be reached at mj_wagner@shaw.ca.
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