Engineering Commons^™

Synthetic Jet Actuator-Based Aircraft Tracking Using A Continuous Robust Nonlinear Control Strategy, N. Ramos-Pedroza, W. Mackunis, M. Reyhanoglu

Publications

A robust nonlinear control law that achieves trajectory tracking control for unmanned aerial vehicles (UAVs) equipped with synthetic jet actuators (SJAs) is presented in this paper. A key challenge in the control design is that the dynamic characteristics of SJAs are nonlinear and contain parametric uncertainty. The challenge resulting from the uncertain SJA actuator parameters is mitigated via innovative algebraic manipulation in the tracking error system derivation along with a robust nonlinear control law employing constant SJA parameter estimates. A key contribution of the paper is a rigorous analysis of the range of SJA actuator parameter uncertainty within which asymptotic …

Flight Dynamics: Flying Qualities Of Handling Factors Are Engineered Into The Aircraft Design, Nihad E. Daidzic

Aviation Department Publications

Flight dynamics is an aerospace engineering discupline that addresses aircraft stability and controllability. It is also mathematically very intensive and is traditionally the most difficult in the pilot training curriculum. Ultimately, it does not matter how good steady-state performance of an aircraft design is if its flying (handling) qualities are deficient. Paradoxically, the first airplane Wright Flyer, was statically and dynamically unstable, had large control authority, and was difficult to fly. We've come a long way since those early days, but stability is still vitally important in aircraft design and flight ops. The focus of this article will be airplane …

Unmanned Aerial Vehicle (Uav): Flight Performance, Fevens Louis Jean

Student Works

It is important that when measuring the sideslip angle and angles of attack during flight test performance of a UAV (Unmanned Aerial Vehicle), to fully understand that the Angles of attack and sideslip are parameters that aid in determining the safety of the flight as they improve stability and control of the aircraft. The disadvantage of the measurement of these angles using this method is low accuracy of measurement due to friction to the potentiometers in connection with the vanes. To counter this, a new sensing method was developed to minimize friction and collect more accurate data. The method is …

Simplex Solutions For Optimal Control Flight Paths In Urban Environments, Michael D. Zollars, Richard G. Cobb, David J. Grymin

Faculty Publications

This paper identifies feasible fight paths for Small Unmanned Aircraft Systems in a highly constrained environment. Optimal control software has long been used for vehicle path planning and has proven most successful when an adequate initial guess is presented flight to an optimal control solver. Leveraging fast geometric planning techniques, a large search space is discretized into a set of simplexes where a Dubins path solution is generated and contained in a polygonal search corridor free of path constraints. Direct optimal control methods are then used to determine the optimal flight path through the newly defined search corridor. Two scenarios …

Cyber-Physical System Characterization And Co-Regulation Of A Quadrotor Uas, Seth E. Doebbeling

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

An Unmanned Aircraft System (UAS) is a Cyber-Physical System (CPS) in which a host of real-time computational tasks contending for shared resources must be cooperatively managed to obtain mission objectives. Traditionally, control of the UAS is designed assuming a fixed, high sampling rate in order to maintain reliable performance and margins of stability. But emerging methods challenge this design by dynamically allocating resources to computational tasks, thereby affecting control and mission performance. To apply these emerging strategies, a characterization and understanding of the effects of timing on control and trajectory following performance is required. Going beyond traditional control evaluation techniques, …

Time Optimal State Feedback Control With Application To A Spacecraft With Cold Gas Propulsion, Samuel J. Kitchen-Mckinley, Sergey V. Drakunov

Publications

A cold gas propulsion system is well suited to provide the required thrust for a small surveyor spacecraft operated near an asteroid or planetary surface. The cold gas propellant can obtained in-situ from local surface or atmospheric constituents. For small spacecraft, the cold gas system may be limited to only on-off control of the main tank where the generated thrust is directly dependent on the tank pressure. As such the thrust will slowly decrease as the propellant is expended. A state feedback, time optimal, control law is developed for a vehicle with propellant is expended. A state feedback, time optimal, …

Static Testing Of Propulsion Elements For Small Multirotor Unmanned Aerial Vehicles, Robert W. Deters, S.C. Kleinke, Michael S. Selig

Publications

The growing use of small multirotor aircraft has increased the interest in having better performance results especially with the propulsion system. The size of the propellers used on these aircraft operate at low Reynolds numbers that are typically less than 200,000. Static performance testing of ten propeller pairs (tractor and pusher) were completed and is the beginning of a systematic test of propellers used on multirotor systems. The propellers chosen for this initial set of tests were selected from four popular quadrotors. Besides testing the propellers provided with the aircraft, propellers that are sold as replacements from third-party companies were …

Stereoscopic 3-D Presentation For Air Traffic Control Digital Radar Displays, Jason G. Russi, Brent T. Langhals, Michael E. Miller, Eric L. Heft

AFIT Patents

An apparatus and method of presenting air traffic data to an air traffic controller are provided. Air traffic data including a two dimensional spatial location and altitude for a plurality of aircraft is received. A disparity value is determined based on the altitude for each aircraft of the plurality of aircraft. Left and right eye images are generated of the plurality of aircraft where at least one of the left and right eye images is based on the determined disparity value. The left and right eye images are simultaneously displayed to the air traffic controller on a display. The simultaneously …

Find Your Center, Nihad E. Daidzic

Aviation Department Publications

No abstract provided.

Adopting Unmanned Flight Operations Into Controlled Airspace, Jennah C. Perry, Johnny Young, Jacqueline Luedtke, Benjamin Cook, Holly Hughes, Allison M. Little, Kyle Wilkerson

Publications

Unmanned aircraft activity is becoming more common within the National Airspace System (NAS) and is expected to dominate the NAS in the near future. Specific procedures for adopting unmanned aircraft into the National Airspace System (NAS).

A variation of the Military Grid Reference System was developed and digitally overlaid onto the radar display. To incorporate this grid system, a customized flight plan database was created for the storage of operator submitted flight plans. Instead of verbal communication, a computer chat system is used for communication because of the low altitude operations in the field.

The Federal Aviation Administration (FAA) has …

Integrating Unmanned Aircraft Operations Into The National Airspace System, Benjamin Cook, Holly Hughes, Allison Little, Kyle Wilkerson, Jennah C. Perry, Johnny Young, Jacqueline Luedtke

Publications

Commercial unmanned aircraft systems (UAS) are expected to dominate the National Airspace System (NAS) in the years to come. One particular barrier preventing integration of UAS into the NAS is the lack of standardized procedures for separating aircraft and communicating with ATC. In preparation for adopting unmanned flight operations into a complex control system, it is important to identify solutions to effectively control UAS in the NAS.

The Joint UAS and ATC Team (JUAT) group has designed several simulated ATC scenarios in order to determine effective solutions for integration. Through the use of digitized radar display overlays that replicate the …

Cockpit In The Systems Engineering Lenses, Aysen K. Taylor, Charles B. Keating, T. Steven Cotter

Engineering Management & Systems Engineering Faculty Publications

The commercial transport aircraft of today vary greatly from early aircraft in regards to how they are controlled and the feedback provided from the machine to the human operator. Automation has improved operational precision and efficiency but at the cost of providing less feedback. Pilots are the last line of defense and current technology cannot provide the human ability to solve novel problems for which no computer logic can be written. The automated cockpits of today have may sub-components that interact in a manner often opaque and unpredictable when a sensor or sub-component fails or even in situations where no …