Bluesky creates new products with Leica CityMapper

Author: Linda Duffy

For Bluesky International Ltd., an aerial mapping and GIS services company based in the UK, staying abreast of rapidly evolving industry trends is key to its success. By recognising the benefits of underutilised technology and developing new products that meet customers’ needs, Bluesky remains competitive in a growing range of markets.

The 3^rd dimension

Interest in digital three-dimensional (3D) models has exploded, spurred by the increasing complexity of urban planning. The desire to visualise buildings and the surrounding landscape in 3D, as well as quickly make measurements and perform analysis, motivated Bluesky to investigate how it could best enter this growth area with a novel, cost-effective approach.

After evaluating the existing technology options, Bluesky concluded that oblique imagery was underutilised in urban mapping and collecting LiDAR and multispectral data separately was too expensive for large areas. Also, the dynamic characteristics of urban space presents unique obstacles for mapping, such as building lean and shade and limited flying time over city centers. The challenge the firm faced was collecting comprehensive survey-grade data to produce a useful 3D model and other related geospatial products at an attractive price point.

Three-in-one data collection

Leica CityMapper is a one-of-a-kind hybrid airborne sensor equipped with a Leica RCD30 CH82 multispectral camera for capturing nadir imagery, a Leica RCD30 CH81 camera for capturing oblique imagery at a 45° angle, and one Leica Hyperion LiDAR sensor. The cameras and sensor collect data simultaneously, which greatly reduces the number of flight lines and time needed to acquire an area of interest.

“Bluesky decided to test CityMapper because its unique capabilities fit our requirements,” says James Eddy, technical director at Bluesky. “For us to deliver high-quality 3D models, we needed survey-grade accuracy and resolution. The three-in-one collection kept our costs down, and the oblique imagery filled a gap that was not being met by other vendors.”

Bluesky selected three test cities in England, then added six more to take advantage of good weather in other parts of the country. Beginning at the end of July 2018 and continuing through August 2018, data was successfully collected in Birmingham, Liverpool, Bristol, London, Manchester and other metro areas. To fully experience the functionality of CityMapper, flight plans included different specifications ranging from 3‒8 centimetre resolution with varying overlap percentages. Bluesky used Leica MissionPro for flight planning and Leica HxMap software to process data from the multiple sensors.

“We found the hardware to be very easy to install and operate with a little training by Leica Geosystems,” states Eddy. “The unit is quite robust and well designed. It worked as soon as we installed it. The data processing is more complicated and required more in-depth training; so are continually improving.”

Variety of products from combined datasets

Using the HxMap 2D and 3D workflow processing software, Bluesky develops a variety of products that serve different needs. For example, the primary products are true colour vertical aerial photography, near infra-red (NIR) vertical aerial photography, true colour oblique photography and LiDAR point clouds. By leveraging the combined datasets, secondary products are also available, such as true orthos, colour infrared, oblique multi-view, classified LiDAR, digital surface models (DSM), digital terrain models (DTM), mesh models and 3D models.

There is interest from a broad range of customers as familiarity with 3D modelling grows. Telecommunications companies recognise benefits for 5G and 6G planning, local governments for urban planning, and utilities for system design and maintenance. Insurance companies use the data to analyse roof details and tree hazards, while emergency responders focus on line of sight, building access, number of floors, and crowd management.

“Our goal is to maintain our competitiveness by adding original useful products to our product line,” says Eddy. “We find that our customers are very interested in urban 3D models and the related image and LiDAR products; the Leica CityMapper collects the data we need in half the time.”