We will demonstrate CodeBlue, a wireless sensor network architecture for medical care. The system is intended for emergency care, disaster response, as well as special purpose applications such as stroke rehabilitation. Our prototype includes a demand driven multicast routing protocol, a device discovery protocol, a simple but expressive query interface designed for medical applications, a location tracking system, and an easy to use graphical user interface. The system runs on two hardware platforms and is integrated with several hardware sensors. We will also demonstrate a miniaturized mote designed specifically for medical use. The routing protocol in CodeBlue is a variation of ADMR, the adaptive, demand-driven multicast routing protocol originally designed by Jorjeta G. Jetcheva and David Johnson for ad-hoc networks. It uses a publish/subscribe model that allows multiple doctors, nurses, or EMTs to submit queries to multiple patients and routes the resulting responses in a way that minimizes overhead. The protocol is tunable to allow selection of the optimal point in the tradeoff between maintenance overhead and node mobility rates. The CodeBlue Query (CBQ) interface allows queries for sensor data with optional filters based on the values of various sensors (e.g. "sample pulse every 10 seconds and send if it is greater than 100 or the blood oxygen is less than 97"). The query is sent from an end user device such as a PDA Copyright is held by the author/owner. SenSys'05, November 2-4, 2005, San Diego, California, USA. ACM 1-59593-054-X/05/0011. and instructs the targeted sensors to send replies on a specific ADMR channel. This allows several devices interested in the same data to subscribe to that channel and get the data as efficiently as possible. We have an easy to use graphical user interface that uses the device discovery protocol to automatically show every device in the network, including a description of the device (sensors present, node id, and the radio connection quality), the node's location (if the optional location tracking system is being used), and the network topology. Clicking on the field for a particular sensor in the description sends out a query for that type of sensor data from that node. As the data for the query streams in, the latest values are displayed in the sensor's description. A detailed history of the data for a particular sensor can be shown by clicking on its icon. The current CodeBlue prototype runs on Telos and MicaZ motes. We support several sensors. Two widely useful ones are a pulse oximetry sensor, used for measuring heart rate and blood oxygen saturation, and a two lead electrocardiograph (EKG), used for continuous cardiac monitoring. We also have a specialized motion analysis board designed specifically for a stroke and Parkinson's disease rehabilitation study at Spaulding Rehabilitation Hospital in Boston. This includes a 3 axis accelerometer for measuring movement, a gyroscope for measuring angular acceleration, as well as an electromyograph (EMG) for measuring the underlying muscle activity. Our demo consists of a poster and a laptop and/or projector showing real-time vital sign information from multiple "patients", as well as a visualization of the changing network topology.
The CodeBlue project at Harvard has proposed a sensor network platform for medical care REF .
Sensor networks for medical care
SenSys '05
Computer Science