The intent of the course is to provide a “top-level” introduction to Modern Flight Control Systems (FCS’s). Basic elements of modern FCS’s are reviewed along with typical basic structures and system elements for modern fly-by-wire FCS’s. Modern analysis and simulation tools are introduced and demonstrated using MATLAB® and SIMULINK®, the advanced engineering computer programs. Students use the basics of MATLAB and the associated Control system Toolbox during the course. Handling qualities criteria and special issues related to modern complex FCS’s such as Pilot Induced Oscillations (PIO’s) are reviewed. The need for systematic closed-loop handling qualities evaluations is emphasized. The effects of common control system feedback implementations are presented using MATLAB and the NTPS variable stability ground simulator (VSGS). Command path shaping and nonlinearities in the command path, such as response limiters, time delay and rate limiting are also introduced and discussed. Course learning objectives are reinforced when students complete two related mini-design/evaluation projects on the VSGS. The objective of the course is to provide a high level of understanding of the Principles, Issues, and Test Methods related to modern FCS’s not to produce FCS designers. Daily review tutorials, oral exams (2) and a final written exam are included in the course.
(Desirable Prerequisite: Completion of T&E 4104)
Anticipated Student Academic Outcomes
Upon successful completion of this course, the student will have a basic understanding of the Principles, Issues, and Test Methods related to modern FCS’s. He/she will:
Be familiar with
1. Block diagram representation of a system and block diagram Algebra.
2. Generic structure of flight control systems.
3. The Poles and zeros formalism of a system
4. Application of Pre-filters in modern flight controls systems.
5. Response feedback technique used by modern flight control systems in order to augment stability of an aircraft.
6. Effects of common parameters feedback on aircraft stability.
7. Basic concepts of systems command and dynamic inversion.
8. General design criteria used for modern flight controls.
1. The relationship between poles location on the S-Plane and dynamic modes of the system.
2. The relationship between transfer functions and frequency response of a system
3. The meaning of Gain and Phase margins and I know how to extract those from the Bode plots.
4. The basic approach in flight testing of a highly augmented aircraft.
1. How to apply the Laplace transformation in solving equations of motion.
2. How to construct Bode plots and how to interpret the frequency response information they retain.
3. How to implement the Root Locus analysis in order to assess the closed loop stability of a system.
4. How to use MATLAB to solve for basic stability augmentation problems.
Sequence of Instruction
Basic Building Blocks (MATLAB Intro)
Analysis Tools/ Stability Criteria
Special MFCS Features
Handling Qualities Issues
Evaluation Methods/ Innovations
Intro to Variable Stability Ground Simulator (VSGS)
Review of In-Flight Simulators
Oral (1) and Written (1) Exams
Texts and Reference Materials
NTPS, Vol. V, “Modern Flight Control Systems”
“Feedback and Control Systems”, Schaum’s Outlines
MATLAB (with Control System Toolbox),
Lectures, Solutions/ Examples using MATLAB,
Mini-Project on VSGS
Process of Evaluation
Oral Report of Mini-Project
Oral (1), Written Exams (1)