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When sensors make sense

29 Oct 2019

Straits Times, 29 Oct 2019, When sensors make sense
Lim Sun Sun For The Straits Times 

In a first for Singapore, the National Parks Board has unveiled a system for tracking animals that triggers alerts to drivers in the vicinity. When sensors detect the presence of animals near Old Upper Thomson Road, an "Animals Ahead" sign is flashed to remind drivers to slow down so as to prevent inadvertent roadkills.
 
Separately, the Singapore Botanic Gardens' new ridge-top walk boasts the OCBC Arboretum, which holds 2,000 trees of more than 200 species. Their development is lovingly monitored by the Ecological Network of Tree Sensors system, which gathers a wealth of data on the climate, tree growth and tree health.
 
These pockets of land where natural phenomena and artificial intelligence collide are a striking illumination of the multifaceted potential of sensors in our networked society.
 
While sensors are remarkable technological items in and of themselves, it is their integration into Internet-connected devices that makes them veritable game changers.
 
Indeed, this transformation of forested land into full-blown cyber-physical spaces through the superimposition of the Internet of Things (IoT) demonstrates the exciting and intriguing possibilities of smart city technologies. IoT networks embedded with sensors, processors and communication hardware facilitate the collection and transmission of data acquired from our natural and built environments. In other words, networked sensors help us make sense of the world through their silent tracking of physical phenomena.
 
But how exactly do they perform this task? Essentially, sensors are devices that can detect and respond to input from the physical environment, including but not limited to light, heat, motion, moisture and pressure.
 
For example, the system in Old Upper Thomson Road comprises cameras that can detect motion through a video analytics-based computer algorithm which distinguishes between animals and humans crossing the road. When video input of animals crossing the road is processed accordingly, the system generates an output that triggers a warning to drivers.
 
At the Botanic Gardens arboretum, one system captures three-dimensional maps of each tree at three-month intervals by emitting laser pulses and measuring differences in their return times with a built-in light sensor.
 
Another performs multi-spectral imaging to track changes in the trees' leaves, via a drone-mounted camera equipped with multiple sensors that can detect light from frequencies invisible to the human eye.
 
Over time, these maps and images enable the botanists to monitor the trees' growth, while weather stations provide information on environmental variables such as sunlight and rainfall. All these inputs are converted by processors into meaningful output signals that can be read by humans and computers, thus generating data that can be transmitted via the Internet for subsequent collation and analysis.
 
Beyond the world of flora and fauna, the use of sensors in our built environment is even more pervasive. Sensors are integrated into large-scale physical infrastructure such as weather stations, utility grids, waste management facilities and security systems. They are routinely used for tracking air quality, water and energy consumption, traffic flows, and the utilisation of public transport and shared spaces.
 
The collection and analysis of such information, also referred to as urban informatics, unleashes distinct possibilities in urban planning because of the copious amounts of highly granular Big Data that can be parsed for more accurate investigation and comprehension of urban trends. Sharpened analyses can translate into real gains in resource optimisation, spatial organisation and security enhancement.
 
But sensors are woven not just into our physical infrastructure.
 
We have ourselves become critical human nodes in a dense and dynamic network of sensors, carrying them in our Internet-connected phones, smart watches, activity trackers and other forms of wearable technology.
 
These devices are capable of measuring our heart rate, blood pressure, release of certain biochemicals, steps walked, time spent exercising, and even sleep cycles. The sensors contained within wearable technology thus gather a considerable corpus of data on our movements, whereabouts and physiological patterns. Mapped against our individual social media footprints, it can produce a very compelling - even if not fully comprehensive - picture of our daily existence.
 
But even as we embrace and marshal the strengths of sensors, as a rapidly technologising society, we need to reach a consensus on when the use of sensors makes sense. After all, sensors facilitate unobtrusive, systematic and large-scale surveillance to an unprecedented degree.
 
As academics Brett Frischmann and Evan Selinger argue in their book Re-engineering Humanity, we run the risk of "surveillance creep", where we become increasingly inured to being watched, monitored and tracked.
 
They caution that with growing reliance on tracking technologies, our societies may gradually transform into surveillance states where we lose all sense of individual freedom, trading privacy for convenience, and liberty for security. There are also dicey ethical issues surrounding the ownership, protection, safeguarding and deployment of surveillance data that have yet to be fully discussed, let alone resolved.
 
In the United States, San Francisco has become the first city to ban the use of facial recognition technology by local agencies such as the police or public transport authority. This ban reflects public concerns about the unreliability and intrusiveness of such surveillance technology.
 
Within our region, the Hong Kong protesters' destruction of lamp posts embedded with sensors and cameras demonstrates the extremes to which people can manifest their resistance to technologies of surveillance.
 
We certainly need not descend to that level of opposition before we ruminate - concertedly and deeply - over the extent to which we should deploy smart city technologies, be it for the benefit of animals, plants or people.
 
• Lim Sun Sun is professor of communication and technology and head of humanities, arts and social sciences at the Singapore University of Technology and Design. She is also a Nominated Member of Parliament.