These devices are network based and the centre has already performed analysis of the networking aspects. In particular we have looked at the adhoc networks and router based networks that can be used to form small networks of these devices. Fort sports and health applications often there is a need to collect information about many different aspects of an activity. This relies on using all the available sensors in the iPhone as well as collecting this data at a high rate up to 100 times per second. This means that a lot data is collected per hour. eg the GPS, compass, 3 axis accelerometer and 3 axis gyroscope requires 9 values every 1/100 second which is 900 values every second which is 54,000 values every minute, which is 3,240,000 values every hour. There is a need to fuse the sensor data together in a meaningful way and store it in a real time sensor database for retrieval at a later date.

We have designed such a sensor based database which works with iPhones and other sensor platforms both proprietary or open. This database is unique in that it allows the data to be sent over a network, stores the data, allows retrieval of the data, allows signal processing of the data using scripts and gives results back over the web as html pages. This database system has been applied to both eHealth and sports monitoring with great success.