Researchers at Oklahoma State University have gained nationwide attention for their efforts to design UAS to help study tornado formation and improve forecasting. This is just one of several projects led by Jamey Jacob, a professor of mechanical and aerospace engineering at the university. Dr. Jacob has worked on projects ranging from solar aircraft to UAS to be flown on Mars.
Your team is designing a UAS to help study tornadoes. What specifically are you hoping to discover from the research? What makes UAS helpful in this research?
The goal is to increase understanding of how tornadoes form, specifically to better learn why only some super cells form cyclones. We want to answer the questions “Why does one storm form a tornado when a similar system sputters out? What are the early signatures of cyclonic genesis?” The goal is to increase warning time for a tornado from the current 10 minutes to possibly an hour. UAS can get in the regions of the storm, namely the lower levels near the boundary layer and lifted condensation level, that radar may not pick up, and measure important meteorological and thermodynamic parameters. We have partnered with several teams, including the University of Oklahoma, UC Boulder, and NOAA, to accomplish this.
Have you been able to test these UAS in severe weather? What have you been able to learn?
Our first flights aren’t expected until 2014 at the earliest. Flying into already formed severe weather systems aren’t the immediate goal, but instead to fly into developing storm systems along the dry line that may turn severe. To date, the only research team to have flown into such a system is from the University of Colorado at Boulder led by Profs. Brian Argrow and Eric Frew. One very interesting thing they discovered is that small UAVs were mostly unhampered by the gusty conditions.
These systems can be used to better understand other weather phenomena within the troposphere, particularly Earth’s boundary layer. Since UAS are capable of flying at low altitude, where most boundary layer related weather phenomena occur, they can measure how convective instabilities form and would be very useful in helping to develop better mesoscale models. The use of UAS provides an opportunity for vertical profiling measurements that are not available from satellites. Weather balloons are currently used for this purpose, but have obvious limitations for control and reusability. The aircraft would carry instruments such as humidity, pressure and temperature probes, anemometers, and sensors to measure turbulent fluxes and would improve models used to predict storm hazards and provide accurate regional forecasting of precipitation. The aircraft can be utilized in the measurement of natural and man-made plumes and dispersion of particles within the atmosphere. The same systems can be used after storms for damage assessment and search and rescue, particularly if outfitted with Electro-Optical (EO)/Infrared (IR) sensors.
How long have you been working with UAS? What initially got you interested in the technology?
I originally started working with UAS as an undergraduate student in the 1980s working on a “tornado chaser” RPV under Prof. Karl Bergey, famed designer of the Piper Cherokee. My next major UAS project was working on designs for Mars aircraft under a NASA workforce development project. There are many problems with flying an aircraft on Mars. Due to the extreme time lag, the vehicle must be completely autonomous unlike the ground rovers which have limited autonomy. Since the atmosphere on Mars is so thin (less than 1 percent that of Earth), the aerodynamic requirements are severe and a high span design is required. Fitting this onboard the launch and reentry vehicle is difficult and wings must either fold origami-style or be inflatable. Working with ILC Dover, manufacturer of NASA’s space suits, we developed inflatable wings that could pack in very small spaces. The ability to fly aircraft where manned aircraft cannot has always been an exciting challenge.
We have projects on using UAS for search and rescue, wildfire monitoring, precision agriculture and infrastructure inspection. We have been developing quiet gasoline aircraft that have equivalent or quieter acoustic signatures than electric aircraft. Though novel platform configurations have been our primary focus, autopilot and navigation research has also been a key area for us in recent years. We work with a number of government and industry partners on research and development in UAS. For example, we have been working with Design Intelligence, Inc. in Norman, OK on solar aircraft designs.
Your students were recently selected by the Department of Homeland Security (DHS) to move to the next phase of the BORDERS Small Unmanned Aircraft System Competition. Can you tell us more about this competition and your students’ designs? What are some of the possible applications for their designs?
The students designed and developed a vehicle named Talos. Though the competition called for a scaled platform, we decided to build a full scale system that can be used for future tests, including Great Horned Owl as well as other UAS research. The entire 16.5 foot span vehicle was built in just over four months. The platform is a versatile design that will continue to be used for hybrid propulsion research. The first flight was delayed by the Moore tornado, but flew two days later. Here’s a video:
What fields have your students gone into after graduation? What do you believe most interests them about UAS?
Students have gone on to a variety of jobs in both manned and unmanned aerospace engineering, ranging from conceptual design to flight testing. Probably what interests students the most is the ability to see the full development of a system from design to building it to flight in a much shorter period of time than it takes with traditional aerospace systems. Adding on top of that the challenge of autonomous operation and system integration makes it an exciting field.
What do you think are the most interesting applications of UAS being developed or tested by others?
While my personal interest has always been with unique configurations, particularly fixed wing platforms that incorporate vertical take-off and landing (VTOL) capabilities, intelligent systems that can adapt to new conditions will change the way we operate UAS in the future and make them truly useful across wide ranges of commercial and civilian users. These intelligent systems will be able to respond to unforeseen events, such as damage to the aircraft, and still safely perform their mission, albeit with reduced capability. Eventually, autopilots will only require rudimentary knowledge about the platform and will tune themselves in flight, enabling true push button control. Once coupled with advanced sense and avoid systems, UAS will not only be safely integrated into the NAS, but be flown by almost any operator. However, this is still a long way off and there is a lot of work that needs to be accomplished before this eventuality happens!