Edmond W. Wilson

Robot System to Search for Signs of Life on Mars

This describes a robot system that can be used to look for the tell-tale signs of life on Mars. Currently, NASA has satellites in orbit that can identify broad regions to explore in its search for life. NASA also has instruments that can examine samples of Martian soil to see if they contain any indications of biological activity. This leaves the problem of deciding specifically where to look for suitable samples in the large area around a landing site. This also describes a robot system that can rapidly search thousands of square meters around the landing position to find sources of biogenic gas samples that may harbor important clues in the search for extra-terrestrial life.

Motion Trajectories for Wide-Area Surveying with a Rover-Based Distributed Spectrometer

A mobile ground survey application that employs remote sensing as a primary means of area coverage is highlighted. It is distinguished from mobile robotic area coverage problems that employ contact or proximity-based sensing. The focus is on a specific concept for performing mobile surveys in search of biogenic gases on planetary surfaces using a distributed spectrometer - a rover-based instrument designed for wide measurement coverage of promising search areas. Navigation algorithms for executing circular and spiral survey trajectories are presented for wide-area distributed spectroscopy and evaluated based on area covered and distance traveled.

Instrumentation of UALR labscale hybrid rocket motor

The Central Arkansas Combustion Group has used a NASA EPSCoR grant to improve the instrumentation and control of its labscale hybrid rocket facility. The research group investigates fundamental aspects of combustion in hybrid rocket motors. This paper describes the new instrumentation, provides examples of measurements taken, and describes novel instrumentation which is in the process of development. A six degree-of-freedom thrust system measures the total work done during a burn to compare the efficiency of fuels and fuel additives. The new system measures the forces and moments in three spatial dimensions. An accurate measure of thrust oscillations will lead to better understanding of the cause and eventual minimization of the oscillations. Plume spectrometers are employed to determine and measure the reaction intermediates and products of combustion at the exhaust. The new control system features an oxygen mass flow controller, which allows the accurate measurement of the oxidant introduced into the motor.

OH Emission Spectra of Hybrid Rocket Motors Using PMMA

Nomenclature ETotal = total energy of a collection of molecules TTranslational = translational energy of a collection of molecules RRotational = rotational energy of a collection of molecules EVibrational = vibrational energy of a collection of molecules EElectronic = electronic energy of a collection of molecules ƒ(?) = Boltzmann of speed of molecules as a function of Kelvin temperature and mass of molecule m = mass of a molecule in kg k = Boltzmann constant T = Kelvin temperature ? = molecular speed Ni = number of molecules occupying energy level i N0 = number of molecules occupying the lowest energy level 0 gi = degeneracy of energy level i Q(T) = partition function evaluated at temperature T [ A ] = concentration of species A in moles per liter e = electron K = equilibrium constant ? = wavelength of radiation ?(?) = density of radiation as a function of wavelength and Kelvin temperature ? ?app = apparatus function which is a measure of the wavelength resolution of a spectrometer En = energy of level n in joules per molecule Inm = intensity of emission from energy level n to energy level m G(?) = Gaussian distribution with independent variables ? and ?

Virtual open path diode laser spectrometer

A virtual, open-path diode laser spectrometer is implemented for use in design and modeling of openpath diode laser spectrometers. The virtual spectrometer is composed of eight modules: a diode laser source module, optical beam correction module, sample module, detection optics module, detector module, signal processing module, data handling module and display module. This modular approach increases the ease of modifying and updating the spectrometer. The virtual spectrometer allows for easy adjustment and visualization of parameters associated with real spectrometers of this design. The virtual spectrometer will be used to model behavior of a distributed, open-path, near-infrared diode laser spectrometer to be mounted on micro rover robots. The purpose of the spectrometer is to measure trace gas levels in hazardous or inaccessible places, such as the surface of Mars for water vapor or around chemical spills, in mines, or for use in covert operations in hostile areas. The virtual spectrometer will also be used to model behavior of an open-path, near-infrared diode laser for measuring chemical species produced in the exhaust plumes of hybrid rockets. Comparisons between actual and virtual spectra are made and discussed. * Graduate Student, Student Member AIAA f Undergraduate Student, Student Member AIAA | Professor, Associate Member AIAA § Professor, Associate Member AIAA Copyright

Field studies of a robot system to measure ground emissions of methane.

A robot system has been developed to search for signs of life on Mars. The system consists of a rover equipped with an open-path spectrometer, and is to designed look for potential biogenic gas emissions from the ground. The paper discusses preliminary field studies with the system. The findings indicate that for this type of application, the spectrometer should be located as close to the ground as is feasible. Also, because wind quickly disperses concentrated gases, frequent measurements are needed in order to determine the location of the source.

A system to sense near-surface atmospheric gases of possible biological origin on Mars

This paper describes a robot system that is equipped with an open path spectrometer proposed to look for signs of indigenous life on Mars. The system was developed to search large areas around a landing site for gases that have a possible biological origin. The rationale for the system, instrumentation and measurements are described. Data is presented from field studies conducted at Mars analog sites in Arkansas. Unique problems addressed include 1) localization of gas sources with a minimal set of equipment; 2) handling both strong (at short measurement distances) and weak (at long distances) laser light signals, with a variable sunlight background; 3) optimal photo detector placement, which depends on measurement distance; 4) managing measurements in wind; and 5) measurements of low concentrations of gases.

Ultraviolet-Visible Spectrometry Characterization of Combustion in Hybrid Rocket Motors

,Small, portable ultraviolet and visible spectrometers can be used to characterize the combustion and regression rates of hybrid rocket and other combustion emission plumes. In this study, two spectrometers, operating in the ultraviolet and visible ranges, were used to measure the hydroxyl radical emission spectrum and the broadband visible emission spectrum of hybrid rocket motors under a variety of oxidizer to fuel ratios. Time and spatial profiles were measured along with regression rates. Correlations were drawn between broadband emission spectra and regression rates. The distribution of hydroxyl radical concentrations was measured as a function of distance from the rocket nozzle, fuel to oxidizer ratio and time into the burn. The fuel grains used were polymethylmethacrylate, PMMA.

National Student Solar Spectrograph Competition overview

The yearly National Student Solar Spectrograph Competition (NSSSC) is Montana Space Grant Consortiums Education and Public Outreach (EP/O) Program for NASAs Interface Region Imaging Spectrograph (IRIS) mission. The NSSSC is designed to give schools with less aerospace activity such as Minority Serving Institutions and Community Colleges an opportunity for hands on real world research experience. The NSSSC provides students from across the country the opportunity to work as part of an undergraduate interdisciplinary team to design, build and test a ground based solar spectrograph. Over the course of nine months, teams come up with their own science goals and then build an instrument to collect data in support of their goals. Teams then travel to Bozeman, MT to demonstrate their instruments and present their results in a competitive science fair environment. This paper and poster will discuss the 2011-2012 competition along with results as well as provide information on the 2012 -2013 competition opportunities.