Intelligent Sensors Monitor Activity and Sleep

A range of intelligent sensor systems helps monitor a patient's vital signs or measure their physical activity.

The SomnoSENS system consists of a small box attached to the patient that observes the patient's vital functions during sleep. Four adhesive electrode pads are used to record an electrocardiogram (ECG), while a finger clip measures the patient's blood oxygen level and pulse rate. A nasal clip and expandable belts around the upper torso monitor breathing, and a movement sensor in the device identifies the patient's body position and registers how much he or she moves.

The SYSVital telemonitoring device offers assistance to patients with heart problems.  The small, lightweight device records heartbeats via a three-channel ECG, identifying minimum and maximum heart rates as well as arterial fibrillation (AF). At the same time, the device records movement, as this assists physicians to evaluate, for instance, the heart rate in connection with physical effort, thus simplifying the diagnosis. The system also permits recovery time to be determined after physical exercise. The data are transferred via a home gateway to an Internet portal where the physician can access the information remotely. A range of optional components can be added to the system to measure other vital data such as blood pressure, weight, or blood sugar level.

The ActiSENS system measures a person's physical activity throughout the day. The user attaches a similar small box containing movement sensors to their belt; the device translates activities into points to provide objective feedback regarding the user's personal level of physical exercise. Points are awarded on the basis of the type of activity: Climbing stairs earns more points than jogging, jogging more than walking, and so on. Zero points are awarded for driving or taking the elevator. During the day, the current score can be displayed on the device at any time. In the evening, the accumulated data for the day can be transferred to a personal computer via Bluetooth transmission and analyzed in greater depth according to previously selected parameters. The data can also be forwarded to a physician for evaluation.

The SomnoSENS and the ActiSENS systems were developed at the Fraunhofer Institute for Integrated Circuits (IIS; Erlangen, Germany), and the SYSVital telemonitoring system was developed by the Fraunhofer Institute for Photonic Microsystems (IPMS; Dresden, Germany).

"SomnoSENS records and stores the data, and transmits them to the base station via a Bluetooth wireless interface. The physician can later evaluate the stored information to make an evidence-based diagnosis,” said Herbert Siegert, spokesperson of the IIS. "The device is attached to the body during sleep and does not hinder sleep comfort due to its miniature size.”

Related Links:
Fraunhofer Institute for Integrated Circuits
Fraunhofer Institute for Photonic Microsystems