Safe as houses

Home monitoring networks could in future protect the elderly and vulnerable in their homes by monitoring their health and identifying behaviour that could indicate problems.

The wireless developer Cambridge Consultants is using the ZigBee wireless network standard for a demonstration system. The company says its solution could ease the load on stretched healthcare resources while helping people preserve their independence.

The person being monitored wears a wireless node which monitors physiological signs and provides zonal location sensing to identify which room the wearer is in. A range of nodes, such as a load sensor on the bed, for example, are used to build up pictures of typical daily activity. Relatives, building supervisors and caregivers could use the system to monitor vulnerable people and identify deviations to patterns in advance of problems, as well as providing the familiar panic button facility.

A fast network data rate allows 'person down' alarms to be complemented by functions ranging from monitoring blood pressure to breathing or heart rate. The demonstration system uses 250 millisecond updates to monitor breathing, in addition to transmitting the data required for position updates.

Raw data can be transmitted to a central location using a broadband line, or analysed and stored locally for review on demand. Social services or doctors could use the information to monitor when intervention might be required, or to notify carers of significant changes in activity patterns.