ight control can be quite signicant, and can lead to dangerous situations when operating in close proximity to obstacles or other aerial vehicles. This work seeks to improve quadrotor positioning performance by formally modeling the wind eects on quadrotor dynamics in order to estimate wind velocities in ight and control the vehicle accordingly. Models for wind disturbances, quadrotor dynamics in wind and onboard measurements are presented and an estimation algorithm is developed for the current wind velocity experienced by the vehicle. This wind estimate is used to improve positioning accuracy by both eliminating the eect of wind on the feedback position control law and adding a wind compensator to mitigate the eect of the expected wind disturbance. Simulation results are presented for multiple scenarios, and work is ongoing for implementation on board a quadrotor testbed.

Wind Disturbance Estimation and Rejection for Quadrotor Position Control

The handling qualities of airplanes have been a subject of considerable interest and concern throughout the history of piloted flight. The Wright Brothers were successful in achieving the first powered flight in large measure because they provided adequate flying qualities for the task at hand. As they became capable of flights of longer duration, they altered the handling qualities of their flying machine to improve piloting performance and to accomplish the expanded tasks. They maintained, throughout, a balance between the amount of stability (or instability) of their airplane in flight and the pilot’s ability to control its movements; they achieved a balance among the airplane’s stability, the airplane’s controllability, and the pilot’s capability. “Handling qualities” represent the integrated value of those and other factors and are defined as “those qualities or characteristics of an aircraft that govern the ease and precision with which a pilot is able to perform the tasks required in support of an aircraft role.” [1] From this definition, it is clear that handling quality is characteristic of the combined performance of the pilot and vehicle acting together as a system in support of an aircraft role. As our industry has matured in the 82 years since the first powered flight, the performance, size, and range of application of the airplane have grown by leaps and bounds. Only the human pilot has remained relatively constant in the system. In the beginning, the challenge was to find the vehicle which, when combined with the inexperienced pilot-candidate, could become airborne, fly in a straight line, and land safely. Longer flights required turns, and ultimately there were additional tasks to be performed. As greater performance capability was achieved, the airplane was flown over increasingly greater ranges of altitude and speed, and the diversity of tasks increased. The continuing challenge was—and still is—to determine what characteristics an airplane should have so that its role can be achieved in the hands of a relatively constant pilot. This challenge has been difficult to answer; the problem is that the quality of handling is intimately linked to the dynamic response characteristics of

https://engineering.purdue.edu/~andrisan/Courses/AAE490A_S2010/Buffer/HCooper.pdf

Handling qualities and pilot evaluation

Type-2 fuzzy logic aggregation of multiple fuzzy controllers for airplane flight control

In this work, a mathematical model of a quadrotor’s dynamics is derived, usingNewton’s and Euler’s laws. A linearized version of the model is obtained, andtherefore a linear controller, the Linear ...

Quadrotor control: modeling, nonlinearcontrol design, and simulation

A mathematical model, suitable for piloted simulation of the flying qualities of helicopters, is a nonlinear, total force and moment model of a single main rotor helicopter. The model has ten degrees of freedom: six rigid body, three rotor flapping, and the rotor rotational degrees of freedom. The rotor model assumes rigid blades with rotor forces and moments radially integrated and summed about the azimuth. The fuselage aerodynamic model uses a detailed representation over a nominal angle of attack and sideslip range of + or - 15 deg., as well as a simplified curve fit at large angles of attack or sideslip. Stabilizing surface aerodynamics are modeled with a lift curve slope between stall limits and a general curve fit for large angles of attack. A generalized stability and control augmentation system is described. Additional computer subroutines provide options for a simplified engine/governor model, atmospheric turbulence, and a linearized six degree of freedom dynamic model for stability and control analysis.

https://ntrs.nasa.gov/api/citations/19830001781/downloads/19830001781.pdf

A mathematical model of a single main rotor helicopter for piloted simulation

: The document is published in support of Military Specification MIL-F-8785B, 'Flying Qualities of Piloted Airplanes.' It was compiled after an extensive literature review and many meetings and discussions with personnel from essentially all concerned civilian and governmental organizations. The primary purpose is to explain the concept and philosophy underlying MIL-F-8785B and to present some of the data and arguments upon which the requirements were based. A secondary purpose is to present what are believed to be the important governing variables in the field of flying qualities and to define their significance and relationship to each other. The significance of such mission- oriented factors as airplane class, flight phase, flight condition, loading and configuration is discussed, as is the treatment of failure states. The document should also, to a degree, serve as a summary of the state of the flying qualities art as determined from operational experience, flight test, experiment, analysis and theory.

Background Information and User Guide for Mil-F-8785B (ASG), 'Military Specification-Flying Qualities of Piloted Airplanes'

: In August 1969, the Air Force and the Naval Air Systems Command adopted MIL-F-8785B(ASG) as the official Military Specification for Flying Qualities of Piloted Airplanes. Since that time effort has been sponsored by the Air Force to further improve the specification document and to increase its applicability in the development of future weapons systems. Results of a study performed by Calspan (formerly Cornell Aeronautical Laboratory) are presented in this report. Changes to the requirements of MIL-F-8785B(ASG) are suggested in the following areas: longitudinal maneuvering dynamics and control gradients, lateral-directional maneuvering dynamics and roll-sideslip coupling, atmospheric disturbance models, stall-spin characteristics, numerous miscellaneous corrections and changes, and additions to Background Information and Users Guide for MIL-F-8785B(ASG). Substantiation data for the recommended changes are also presented. (Author)

Charles R. Chalk

Papers

Background Information and User Guide for Mil-F-8785B (ASG), 'Military Specification-Flying Qualities of Piloted Airplanes'

Revisions of MIL-F-8785B(ASG) Proposed by Cornell Aeronautical Laboratory.