Author: Publisher:
ISBN:
Category :
Languages : en
Pages : 48
Book Description
An Exploratory Investigation of the Flight Dynamics Effects of Rotor Rpm Variations and Rotor State Feedback in Hover
An Exploratory Investigation of the Flight Dynamics Effects of Rotor Rpm Variations and Rotor State Feedback in Hover
Author: National Aeronautics and Space Administration (NASA)Publisher: Createspace Independent Publishing Platform
ISBN: 9781722069940
Category :
Languages : en
Pages : 46
Book Description
This paper presents the results of an analytical study conducted to investigate airframe/engine interface dynamics, and the influence of rotor speed variations on the flight dynamics of the helicopter in hover, and to explore the potential benefits of using rotor states as additional feedback signals in the flight control system. The analytical investigation required the development of a parametric high-order helicopter hover model, which included heave/yaw body motion, the rotor speed degree of freedom, rotor blade motion in flapping and lead-lag, inflow dynamics, a drive train model with a flexible rotor shaft, and an engine/rpm governor. First, the model was used to gain insight into the engine/drive train/rotor system dynamics and to obtain an improved simple formula for easy estimation of the dominant first torsional mode, which is important in the dynamic integration of the engine and airframe system. Then, a linearized version of the model was used to investigate the effects of rotor speed variations and rotor state feedback on helicopter flight dynamics. Results show that, by including rotor speed variations, the effective vertical damping decreases significantly from that calculated with a constant speed assumption, thereby providing a better correlation with flight test data. Higher closed-loop bandwidths appear to be more readily achievable with rotor state feedback. The results also indicate that both aircraft and rotor flapping responses to gust disturbance are significantly attenuated when rotor state feedback is used. Chen, Robert T. N. Ames Research Center RTOP 505-59-36...
Scientific and Technical Aerospace Reports
Author: Monthly Catalog of United States Government Publications
Author: Integrated Flight/propulsion Control with Variable Rotor Speed Command for Rotorcraft
Author: Stanford University. Department of Aeronautics and AstronauticsPublisher:
ISBN:
Category :
Languages : en
Pages : 246
Book Description
Monthly Catalogue, United States Public Documents
Author: Publisher:
ISBN:
Category : Government publications
Languages : en
Pages : 1592
Book Description
International Aerospace Abstracts
Author: Aeronautical Enginnering: A Cumulative Index to a Continuing Bibliography (supplement 312)
Author: Aeronautical Engineering
Author: Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 580
Book Description
A selection of annotated references to unclassified reports and journal articles that were introduced into the NASA scientific and technical information system and announced in Scientific and technical aerospace reports (STAR) and International aerospace abstracts (IAA)
Journal of the American Helicopter Society
Author: American Helicopter SocietyPublisher:
ISBN:
Category : Helicopters
Languages : en
Pages : 628
Book Description