Distributed System for Spaceflight Biomedical Support

Over the past three decades, scores of biomedical monitoring devices have been deployed aboard U.S. spacecraft and the International Space Station. These have enabled collection of heart rate, respiration rate, temperature, sleep/wake activity, carbon dioxide, ultrasound images, and numerous other physiological and environmental parameters. However, nearly all such measurement devices were designed as stand-alone systems, unable to operate together, synchronize data streams, be easily augmented with new sensors, or coordinate in any way with therapeutic devices. Some systems under development are being designed to record multiple signals. However, even these composite systems remain as stand-alone devices. Currently, there is no flight-ready platform that can (i) automatically bring together data from disparate human and environment sensors for diagnosis, (ii) make acquired data available from nearly any location or display device, or (iii) intelligently incorporate computer aided diagnostic or therapeutic components of the spaceflight medical system.

We thus developed a prototype platform, called SpaceMED, that can seamlessly integrate disparate biomedical and environmental sensors and effectors, including future decision-support and therapeutic systems. The SpaceMED v2.2 prototype software platform consists of three primary components: (1) MEDcomm: a suite of listener services that continuously monitor the external environment to detect and connect with both wired devices (e.g., ethernet, USB, A/V feeds) and wireless devices (e.g., Bluetooth, radio, WiFi), (2) MEDproxy: a middle layer that enables any data or control signals that are "published" to be delivered to the appropriate receiving systems (as well as being archived), and (3) MEDview: a graphical user interface for query and display of the collected data and to facilitate device control.

In addition to developing the SpaceMED software, we demonstrated the integration of a range of hardware devices in SpaceMED. We integrated seven classes of commercial-off-the-shelf (COTS) hardware systems with SpaceMED, using a variety of communication standards: Bluetooth, 802.15.4 radio communication (using both ANT and TinyOS standards), and USB mass storage devices. The available devices--including sensors for 3- and 12-lead ECG (electrocardiogram), EMG (electromyography), heart rate, temperature, accelerometry, environmental carbon dioxide, and files stored on USB mass storage devices (e.g., Flash drives and memory sticks)--are automatically discovered, connections are created, and data is acquired and communicated through the system without human intervention. SpaceMED is able to deliver both file-based and telemetry-based data to NASA's Exploration Medical Capabilities Human Research Program element (ExMC's) Exploration Medical System Demonstration (EMSD) software, including a 12-lead ECG, file-based data such as the medical consumables tracking system files, digital still and video communication, near-infrared neuroimaging (NIN), carbon dioxide monitors, and radio-frequency identification (RFID) tagging devices. The system is designed to facilitate incorporation of future medical and environmental hardware.

The SpaceMED prototype platform (1) demonstrates the feasibility of seamless interoperation of components not otherwise intended to work together, with minimal human intervention, (2) validates the approach for integrating telemetrically gathered physiological data streams from multiple devices and display of time-synchronized data from multiple nodes as the information is acquired, along with file-based data, (3) provides a prototype platform for future medical capabilities integration, including new sensors, decision support, therapeutic systems, and device control, (4) leverages previously funded projects from NASA Ames, NASA Glenn, NASA Johnson Space Center, and the National Space Biomedical Research Institute (NSBRI), and (5) provides spin-off potential for use in a variety of Earth-based clinical settings.