Arun Mangalam, Tao Systems president, is working on several Dryden projects, including one involving the G-III aircraft behind him. (NASA Photo / Tony Landis)
› View Larger Image Mangalam Brings Dryden Ideas, Technology
Tao of Systems Integration of Hampton, Va., has developed technology that will revolutionize aircraft control. Small Business Innovative Research funds were among the factors that have enabled the company to pursue concepts and build on them for decades.
Arun Mangalam, Tao Systems president, continues to mature technology validated and advanced through 11 SBIR contracts. Mangalam was principal investigator and collaborator for a number of those advancements. Some of those breakthroughs were from proposal requests from Dryden that resulted in the Distributed Aerodynamic Sensing and Processing, or DASP, Toolbox (see related story).
During the past decade, working toward using flow physics to determine lift and drag to seek aero efficiencies has been the heart of Tao Systems' business. To that end, the company has earned 14 patents for sensors and signal processing. The payoffs for gaining aero efficiencies are reflected in increased fuel efficiency and range and improved safety.
Mangalam also is at Dryden working on the Aeronautics Research Mission Directorate Environmentally Responsible Aviation experiments with the G-III aircraft. That aircraft is being used for in-flight research of a new laminar flow glove on the wing and new composite actuators.
He will be assisting with sensors and signal processing to assess the aerodynamics of the actuators on the G-III – essentially, an SBIR phase III agreement, he said. (Phase I agreements are commonly paper studies, Phase II agreements are funded and Phase III is the point at which a technology has been the object of interest and has received capital for further research.) In addition to looking at the transition from smooth to turbulent air, Dryden partners at the Air Force Research Laboratory are looking at the efficiency of the new actuators.
"How do you get loads and moments from these flow characteristics? That's the question we are trying to answer," Mangalam said. "It's much faster to measure the flow physics than to look at the response on the structure. To do that, we will be looking for surface flow measurements and will be obtaining critical features from those measurements, like stagnation point, effective flow angularity and flow separation point."
In addition to earning undergraduate and graduate degrees in physics and computer science from the College of William and Mary, Williamsburg, Va., Mangalam is working on a doctorate at Virginia Polytechnic Institute and State University, Blacksburg, in mechanical engineering with a specialization in aeroelasticity. Essentially, everything involving flow physics and structural dynamics and control are his key interests.
"My interest is in the physics of flows and structures and how to use and exploit that to achieve whatever objective you are seeking," he said. "In the case of aircraft, you are trying to achieve aerodynamic efficiency, structural reliability, safety and performance."
He is enthusiastic about his work at Dryden.
"I enjoy what I do, but this is going to take it closer to the action. Flight testing is where it all happens," Mangalam said.
Work furthered with SBIR funding helped enable his current opportunities at Dryden.
"SBIR is sort of like seed funding for an idea. Sometimes these ideas in aeronautics cost a lot just to implement because testing facilities are very expensive, materials are very expensive and the time required to do a good job is quite intensive. So I think SBIR funding allows you to commit resources," he added.
SBIR agreements can also lead to resources that have more than a dollar value, he said.
"We work with a lot of organizations – agencies and industry as well as academia – from the U.S. and Europe. A lot of products are being sold internationally and [SBIR support] helped in refining those products. Even now we are collaborating with people from Canada, France and some in the United Kingdom, so that we can come up with a better result in the United States. We are also working with U.S. researchers and SBIR definitely helps in that process."
However, there is no environment like that of flight to determine if everything works as planned.
"In wind tunnels, flow angularity is not well defined, especially near and past stall angles. In the linear small flow regime, there are good solutions available from computational methods.
"Once you get enough flow separation, predicting the static and especially the dynamic test results becomes very challenging. When you get near stall, there is a high degree of uncertainty in terms of prediction. And where do you think nature is optimizing – it's near stall. Everything is near stall and past stall.
"We also see the problem when you try to scale test results from wind tunnel to flight. It doesn't match, because it's hard to match boundary conditions like the effective flow angularity in the presence of flow separation."
Some aircraft are sensitive to gusts, and gust load alleviation is another of Tao Systems' interests.
"We tested out a gust load-alleviation controller under an Air Force program at NASA Langley's Transonic Dynamics Wind Tunnel. Those technologies could very well be used on aircraft right now. An issue that needs to be addressed is the environmental effect on sensors.
"The Air Force is working to come up with a more rugged solution to the sensors. We are collaborating with companies to make the transition to military aircraft first and ultimately on civilian aircraft," he said.
Determining the aerodynamic loads on the tail and wings by gusts in real time is a first step. Then a controller would need to be developed to automatically adjust for the loads. These concepts have led Tao Systems to a different vision of what controls of the future should look like.
"Would it be useful to have a system where you could 'fly by feel,' just like birds at various flight conditions? Fly-by-feel means you are able to sense the aerodynamics in a very quantitative way. An aircraft could react immediately to suit mission objectives, like being able to loiter for a long time and focus on range and endurance, or dash not unlike rapid maneuvering of insects.
"In order to do that you have to have a flow physics model that works – validated for angles well beyond stall and including flow separation – numerically and experimentally and numerically. Through our collaborations, we have the beginnings of that and we would like to extend that further," Mangalam said.
And there would be other benefits to the fly-by-feel concept.
"Fly-by-feel is physics-based control not just for subsonic and transonic flows, but for supersonic flows, where you can sense the loads in real time and react. What nature is very good at is exploiting the energy available in the environment.
"For example, take crosswinds or atmospheric turbulence. We generally avoid these conditions, but insects use them to generate thrust for themselves or gain altitude. The fly-by-feel concept and implementation enables aircraft to sense and exploit the environment regardless of flight regime."
Whatever the controls of the future look like, one thing seems certain – Tao Systems will have a role in developing it.