A sense of security

2 min read

An intelligent sensing system will use wireless technology, GPS and a suite of sensors for real-time monitoring of independent elderly people at home.

The €1.85m (£1.2m) EU-funded Complete Ambient Assisted Living Experiment (CAALYX) project will develop and test a light, mobile device to monitor a number of vital signs and transmit the information to an intelligent data-logging system.

While the two-year project is to be led by Spanish telecommunications firm Telefonica, Plymouth University will take a lead role in developing the technology.

Dr Maged Boulos from the university's School of Health Informatics said the finished system will be able to monitor a wide range of physical parameters. These are likely to include ECG monitoring, oxygen saturation sensors, heart rate and respiratory measurements. It has not been decided exactly which sensors will be included, but Boulos is sure fall detection technology will be a crucial component of the system.

'We are targeting older, healthy people and for them fall detection is an important issue,' he said. 'Even if someone does not hurt themselves when they fall it can have serious consequences for their confidence and can limit their future activity.'

Fall prediction

Limerick University is to develop the fall detection accelerometers, which will also be able to predict falls. Most fall sensors use cameras that must first learn a person's 'normal' movements to be effective. These new sensors will be able to predict falls just before they happen and be adaptable enough for use anywhere so will give the wearer a greater degree of confidence even outside the home, said Boulos.

Information from the sensors, which are worn belt-style, will be sent via Bluetooth to a mobile device that the person will be able to carry around with them wherever they are. Key to the system is that this portable device — in effect a modified mobile phone — will not be continuously communicating in real-time.

There are a number of reasons for this, says Boulos. First, allowing the mobile to collect the data rather than continuously stream it to a remote server means that bandwidth is saved. It is also far more power-efficient than a system that has to continuously transmit data and pick up real-time geographic information via GPS. Most important, it means people will not feel as if their every move is being watched.

The device will use algorithms that can pick up on any dangerous change in the person's vital signs or if one of the sensor feeds falls outside of acceptable parameters. If this occurs the system locates his or her position using GPS then triggers an alarm to alert the emergency services.

The project aims to use as many standard and commercial technologies as possible. For example, its German partner Corscience is to provide its ECG monitor, which is worn belt-style around the chest.

Boulos said the project might also use a webcam set-up with an easy-to-use PC to allow carers in remote locations to call in and check on their charges during the day.

'The key is we are planning an open system with plug-and-play architecture so the mobile sensor networks can accept any new sensors being plugged in,' said Boulos of the system's proposed modular design.

'This means that follow-on projects could look into niche markets such as sensors for elderly diabetics using blood-glucose sensors.'

In time, the project is also likely to be compatible with the Galileo system of satellites as well as enhanced location technologies such as assisted GPS.

Towards the end of next year a prototype system will be tested with elderly users in Italy, and a full-scale demonstration will take place in a smart home based at Telefonica's headquarters in Valledolid, Spain at around the same time.