Acoustic Sensors Making the City Smarter

By November 17, 2014
capter les bruits pour la smart city

The northern Spanish city of Santander has been providing a testing ground for an EU-funded research initiative which used acoustic processing units to help optimise traffic flows, control energy consumption and improve security.

Under the European Union joint-funded Future Internet Research and Experimentation (FIRE) R&D initiative, projects are being run in cities with a view to improving traffic flow, controlling energy consumption and enhancing security.  One of these projects, entitled EAR-IT, brought together six European partners and a small Chinese company called Wuxi Smart Sensing Stars, supported by €1.45 million worth of funding under the Information and Communication Technology section of the EU’s current (7th) Framework Programme for Research and Development (FP7 ICT). Researchers on the project have taken the latest acoustic technology developed in laboratories and sought to apply it to real-life environments. Santander in northern Spain provided the test bed for a two-year experiment. As part of the SmartSantander programme, some 12,000 sensors were placed on the city’s lamp-posts and data gathered in order to assess any problems or needs and help come up with solutions in real time. EAR-IT closed down in September and the project is due to be fully wrapped up by the end of the year.

Towards smoother traffic flow

The EAR-IT team first set out to record traffic movements in Santander. A number of startups all over the world have already been developing software solutions in this field and there is nothing new about installing sensors in cities to record a range of factors and pinpoint problems. What was novel about the EAR-IT approach was that it drew data from acoustic processing units (APUs) rather than visual recordings or the widely-used pressure sensors. Project coordinator Professor Pedro Maló explains how EAR-IT’s outdoor use case focused on traffic flow monitoring at a junction near Santander’s hospital and the analysis of traffic density on two main city streets. “The complex junction was the scene of quite a few traffic incidents. Traffic comes in a variety of directions and emergency vehicles are trying to get through. EAR-IT has set up sensors which ‘hear’ sirens and then trigger other sensors to track the vehicle. This data is then used to change traffic lights in the ambulance’s favour.”  Results showed that recording city sounds can provide a means of responding faster to traffic problems when they occur. The acoustic sensors even proved able to count the number of vehicles passing by, giving the same results as electromagnetic induction sensors installed under the tarmac.  The researchers have concluded that APUs could therefore replace this much more time-consuming and costly approach to street data gathering.

Optimising energy consumption and enhancing security

EAR-IT’s indoor use case consisted of trialling the use of acoustic data from inside houses and buildings to assess what is going on in a room and how many people are currently in it so as to adjust energy consumption.  “Windows can be made to open, curtains close and lights and heating turn on and off automatically,” explains Maló, thus providing another effective tool for the ‘connected’ building or home to adapt to circumstances in real time.  Given Europe’s ageing population, one key application could be using acoustic sensors to verify that a person is safe and sound at home. APUs could for instance transmit a distress message if the occupant has a fall, letting healthcare providers and family know whether they need to intervene. These technologies already exist. A carpet developed at the University of Manchester in the UK in 2012 is able to signal a fall and a sensor-based system has been developed in San Francisco by a web technologist whose house spontaneously tweets about events that might require its owner to react. The EAR-IT project is hardly revolutionary but the APUs have proved they can enable a range of applications which are already available to be combined into a single system. One might see this as a sort of ‘Swiss Army knife’ for the smart city, its multifunction capability helping to reduce costs.  Investors might well be interested in backing the approach and it might also appeal to city authorities who have so far been wary of embracing ICT-based monitoring.

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