曝光台 注意防骗
网曝天猫店富美金盛家居专营店坑蒙拐骗欺诈消费者
– Inner-loop pitch rate feedback used to reduce effect of pitch moment
due to thrust changes.
– Outer-loop 3-input/3-output, Hµ loop shaping to control normal and
forward acceleration and incidence.
– Weight selection similar to classical loop-shaping.
51 / 71
– Four linear point designs gain-scheduled throughout flight envelope.
• Controller implemented in observer form.
• Interpolated controller gains and interpolated controller outputs.
– Hµloop shaping techniques also used to synthesize an integrated
longitudinal/lateral flight and propulsions control system for VAAC.
UK - VAAC Control Strategies
• Linear, parameter-varying (LPV) controller
–System dynamics written as LTI models whose state-space coefficients
are a function of scheduling variable(s).
–LPV Hµ loop shaping uses LPV model of nonlinear aircraft dynamics to
directly synthesize a scheduled LPV controller.
–Successfully implemented at tested between 1995 and 1998.
52 / 71
Israel
• Light, multi-mission fighter “Lavi”
– Initial flight test: 31 Dec 86, program terminated: 30 Aug 87
– Flight control laws
• Classical technique with optimal control methods used in
preliminary design process.
– Lessons learned: Relationship between control design parameters and
flying qualities.
53 / 71
• UAVs
Russia
SU-27
SU-30MK
54 / 71
SU-35 SuperFlanker
Russia
MIG-29 TU-22
55 / 71
SU-37 Terminator
SU-27
Russia
SU-30MK
56 / 71
TU-160
SU-37
Russia
Extensive history of military/commercial aircraft development.
• English language literature on Russian industry flight control design
techniques is limited.
Sukhoi 37 FBW flight controller
• Quad redundant Digital FCS
• Design requirements
57 / 71
– Good handling qualities.
– Optimal trimming.
– Reconfigurable under flight control system failures to maximize control
moments and trim configuration.
• Adaptive controller designed to eliminate small amplitude self-induced
oscillations due to actuator nonlinearities.
Russia - SU-37 Aircraft
• Canards and thrust vectoring (TV loop not shown.).
• Longitudinal controller synthesized with classical control methods.
58 / 71
Dead zone
Wagner Functions– unsteady aerodynamics
United States of America (USA)
Commerical
• Boeing (McDonnell Douglas)
– B-717, B-737, B-747, B-757, B-767, B-777
• Honeywell
Military
• Lockheed Martin (General Dynamics)
59 / 71
– F-16, F-22, F-35 (JSF)
• Northrup Grumann
– F-14, F-20, B-2
• Boeing (McDonnell Douglas, North American Rockwell)
– B-52, B-1B, C-17 C-40A, F/A-18, KC-10
• Honeywell
USA
B-2 Spirit
B-747
60 / 71
AV-8 Harrier
B-747
C-5 Starlifter
USA
F-117A
61 / 71
B-747
UCAV
U-2
F/A-18E/F
USA - 1947
B-377 Stratocruiser
62 / 71
B-747
USA Flight Control Specifications
Multivariable Control
• Multiple sensors, disturbances, objectives, surfaces (TV) with coupling.
• Military specifications focus on SISO, loop-at-a-time analysis
Multivariable Control Design Guidelines (1996)
• Honeywell Research Labs, Lockheed Ft. Worth, Lockheed Skunk Works
63 / 71
• Eigenstructure assignment, dynamic inversion, m-synthesis
• F-177, YF-22 and MCT/F-16
• Report provides a reference point for the US Air Force to evaluate the design
of future flight control systems.
B-2 Flight Controls
64 / 71
Boeing
The Boeing Company
• Largest manufacturer of aircraft in the world.
• Merger of Boeing, Rockwell International and McDonnell Douglas
– Variety of approaches to flight control design
Multivariable Flight Control
65 / 71
• First application in 1978 as part of a NASA research program.
• Since 1980s, multivariable control as been applied to a number of aircraft
–Multivariable control with classical frequency-domain interpretations.
– Guidelines to transform design requirements into math
– Training of control engineers
– User-friendly control software programs.
Boeing
Multivariable Control Design
• LQR/LQG based
• Performance and robustness
• Direct tradeoff between command response, control activity,
66 / 71
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址:
航空资料31(60)