The Mars Gravity Biosatellite: Innovations in Murine Motion Analysis and Life Support

Abstract

The MIT-based Mars Gravity Biosatellite payload engineering team has been engaged in designing and prototyping sensor and control systems for deployment within the rodent housing zone of the satellite, including novel video processing and atmospheric management tools. The video module will be a fully autonomous real-time analysis system that takes raw video footage of the specimen mice as input and distills those parameters which are of primary physiological importance from a scientific research perspective. Such signals include activity level, average velocity and rearing behavior, all of which will serve as indicators of animal health and vestibular function within the artificial gravity environment. Unlike raw video, these parameters require minimal storage space and can be readily transmitted to earth over a radio link of very low bandwidth. We present a collection of custom processing algorithms which are capable of accurately correlating video sequences with certain modes of behavior. We additionally present results which validate the performance of the proposed Mars Gravity atmospheric quality control module. The specific challenges of an extended-duration re-entry mission have required the development of low-mass and low-power systems for particulate filtration and contaminant control. Our approach has taken advantage of commercial off-the-shelf hardware where possible. Atmospherics systems on board the biosatellite are designed to maintain air quality and to continuously circulate clean, conditioned air to all fifteen specimen chambers. Sensors within the air circulation loop will monitor the concentrations of carbon dioxide, ammonia and other contaminants. Our design calls for a feedback system linked to the payload computer to control the temperature and humidity levels while particulate filters will remove dander, dust and other airborne contaminants.