Leveraging Satellite Remote Sensing Technology to Build a Safer Hong Kong

New technological developments can bring about transformation in the construction industry by improving efficiency. Recently, world-renowned geologist Mei-Po KWAN – who is also the Director of the Space and Earth Information Institute and Professor of Geography and Resource Management at The Chinese University of Hong Kong (CUHK) – spoke at a See What I See event about the potential of satellite remote sensing and other advanced technologies to enhance safety of both construction sites and Hong Kong’s overall infrastructure, benefitting both the construction industry and social development.

Scientific Support for Satellite Surveillance

Founded in 2015, CUHK’s Institute of Space and Earth Information (ISEIS) focuses on research in space and Earth information science. It uses its own ground-based satellite receiving station to carry out research on geospatial intelligence (GeoAI), health geography, multi-source remote sensing environment monitoring and virtual geographic environments (VGE). Through its environmental monitoring and study of changes on the ground, it provides scientific support and solutions for urban planning and other areas of activity.

Professor KWAN explains: “So what do we actually do? We are combining sky, space, Earth and human beings. We not only receive information from remote sensing satellites, unmanned aerial vehicles (UAV) and the Bei Dou satellite, but also use proprietary technology to process different satellite images and AI to process different data.”

In the past, public concerns were often raised when problems of structural deformation and even settlement occurred at construction sites. Satellite remote sensing imagery can help building work and structures to be more effectively monitored, as well as project progress, quality and site safety. According to Professor KWAN, with these technologies helping to improve site safety, the construction industry could continue to attract new blood. More importantly, satellite remote sensing, through real-time monitoring, can observe the condition of structures under construction, detecting any deformation and giving advanced warning.

Currently, Hong Kong International Airport and the Hong Kong portion of the Hong Kong-Zhuhai-Macau Bridge are using satellite remote sensing to monitor for infrastructural deformation and evaluate potential risks. The technology offers five times more frequent observations than traditional ground surveillance and its accuracy is as precise as two millimetres.

Urban Physical Examination Increases Building and Infrastructural Safety

As early as year 2000, the Hong Kong Innovation and Technology Bureau was collaborating with the National Ministry of Science and Technology on a radar remote sensing project which included safety testing and evaluation of infrastructural facilities and building structures. Termed ‘urban physical examination’, this aimed to discover potential issues and risks as early as possible and ensure that city operations could safely continue.

ISEIS is using remote sensing to collect information from multiple sources, including synthetic aperture radar (SAR) and optical images, integrated with ground measurement data for analysis. All these collected data could also be applied to urban planning, environment surveillance, disaster emergency risk assessment or smart transportation systems, as well as to construction safety and promotion.

Professor KWAN explained that the use of images created with interferometric synthetic aperture radar (InSAR) time series to monitor building deformation and issue warnings has already helped to predict serious disasters and minimise losses.

ISEIS has also used unmanned aerial systems and low altitude sensing to monitor construction sites, detecting issues such as waste accumulation, improper storage and damaged safety nets so that preventative measures could be implemented.

The institute has built a 3D noise modelling system to assess the noise level of each and every floor of every building in Hong Kong. This technology that could also be usefully applied at construction sites to measure and ultimately alleviate their noise problems.

“Industrial safety always involves human activity. Mobile sensing technologies, using equipment such as smartphones to collect data, could examine site environments, noise levels and air quality for the implementation of appropriate preventive measures and improvement of site safety,” Prof. KWAN observed.

The Professor added that satellite remote sensing integrated with other data and sensing technologies would help to build a ‘Smart City Environment Sensing System’. This would monitor health-affecting factors such as air and noise pollution to enable effective preventative measures to be emplaced – a so-called ‘urban physical examination’. Professor KWAN remarked that it is encouraging that HKCU would launch the first Hong Kong-financed satellite for monitoring and research, as it may prove vital in building a healthier and safer city.

Using Science and Technology to Strengthen Knowledge Exchange

As Ir Thomas Ho, Chairman of CIC, said: “Making use of technology is indeed very important to the construction industry. For this purpose, we have to seize every opportunity to communicate with different parties, especially those on the mainland. To this end, the Council organised the ‘Forum of China ConTech Development and the Future of Hong Kong’s Construction Industry’ to discuss the latest trends in Mainland construction technologies, and developments and opportunities in Hong Kong’s construction industry. The Forum has been a very successful platform for scientific and technological exchange and cooperation between Hong Kong and the Greater Bay Area.”

On a related note, smart facilities management systems have become essential to property management. The Smart Facilities Management Control Centre located at the Kowloon Bay campus of the Hong Kong Institute of Construction was established at end of August 2023. It is a collaborative space and a showcase for an array of technologies such as digital twin, BIM, AI and big data, and promotes digitalisation of property management and exchanges of technological information for enhancing the overall quality and efficiency of property management.

In the future, CIC and other industry organisations will continue to work together on providing exchanges and training on the latest construction technologies. Together, the construction industry will elevate its efficiency and safety standards and create a better future for all.