The biosensors that will be used during exploration missions must be small, robust and use as little electrical power as possible. Additionally, they must survive in and around an environment that is hostile to most sensors: the human body.
BioWATCH unit shown for size next to an ECG lead and a ruler.
Data from sensors measuring physiological performance must be properly collected and managed. Because biosensors are frequently worn on the body, lightweight and wireless systems are preferred, but have not been readily available. Based on a desire to improve biosensor data management onboard the International Space Station (ISS), NASA funded a Small Business Innovation Research (SBIR) grant for ZIN Technologies to develop a wearable data collection, storage and transmission device. ZIN developed a device called Biomedical Wireless and Ambulatory Telemetry for Crew Health (BioWATCH), which can be easily reconfigured between numerous sensors and data transmission protocols. Additionally, BioWATCH can simultaneously support up to five sensors and their data streams.
Reconfiguration is easy because BioWATCH was designed to use CompactFlash cards and the control unit runs a form of the Unix operating system. As such, integrating a new sensor is rapid and inexpensive. BioWATCH is able to communicate using standard wireless protocols such as 802.11, Bluetooth, EDGE, EVDO, and wired protocols such as USB, Ethernet and RS-232.
Based on the success of the initial prototype modules, ZIN and the Cleveland Clinic teamed to deploy BioWATCH in an application monitoring heart rhythm in patients following a procedure designed to eliminate a heart rhythm irregularity known as atrial fibrillation.
BioWATCH has been demonstrated to be compatible with the following classes of biosensors: ECG, EEG, EMG, EOG, heart rate, blood glucose, blood pressure, temperature, and pulse oximeters.
NASA and ZIN Technologies Share NorTech Innovation Award
As a spin-off from other research efforts, Glenn has developed sensors that are capable of taking metabolic measurements inside space suits. One example is the Portable Unit for Metabolic Analysis (PUMA).
PUMA electronics box
PUMA data from actual test subject
The PUMA measures the amount of oxygen an astronaut consumes and the amount of carbon dioxide produced. When combined with PUMA’s heart rate measurement, PUMA software quantifies how hard the astronaut is working. This information helps the astronaut manage and conserve the limited supply of consumable resources available within the space suit. Additionally, the data are used to present the most accurate picture of the astronaut’s fitness level and to prevent the astronaut from working past the point of exhaustion.
PUMA is battery operated and self-contained, featuring an electronics box that fits into a small, wearable pack. It was deployed during NASA’s Extreme Environment Mission Operations (NEEMO) mission in May 2007. Twice during the mission, the NEEMO crew wore the PUMA for twenty minutes to determine their resting metabolic rate. This activity was PUMA’s first use in an environment different from Earth’s standard atmosphere. Pressure in Aquarius was 2.5 times higher than is experienced at sea level, which may cause changes in human metabolic performance.
PUMA being used in Aquarius, NOAA’s underwater ocean laboratory, during NASA’s NEEMO-12 mission.
Glenn has a long history in developing Micro-Electro-Mechanical Systems (MEMS) sensors for the harsh environments found in aircraft engines. Rather than use the traditional silicon as the substrate material, Glenn uses silicon carbide, which is much more durable. This technology has already been used to produce compact oxygen and carbon dioxide sensors operating within a mask system used to detect the onset of an asthma attack. Other GRC MEMS systems can be used to quantify the amount of dust present in a lunar or Martian habitat.