Steps
Step 1
Mission Analysis
This step conducts in-depth analysis of aircraft flying qualities, evaluating system stability, damping characteristics and control response. Flying qualities analysis is a critical element in aircraft design, evaluating levels based on MIL-STD-1797 or GJB standards, providing performance requirements for control law design. Multi-dimensional evaluation through eigenvalue analysis, frequency domain response and time domain simulation.
• Perform eigenvalue analysis using MATLAB/Simulink, calculate damping ratios and natural frequencies of short-period, phugoid, roll, yaw modes
• Plot Bode diagrams and root locus, analyze stability margins, determine phase margin and gain margin
• Rate flying qualities levels according to MIL-STD-1797B standard, distinguish Level 1/2/3 flying qualities
Deliverable: Flying qualities analysis report (including eigenvalue table, modal parameters, Bode plots, root locus, quality level assessment) | Quality standard: Analysis method compliant with standards, accurate modal parameters, correct quality rating
Step 2
Airfoil Selection and Analysis
This step conducts in-depth analysis of aircraft flying qualities, evaluating system stability, damping characteristics and control response. Flying qualities analysis is a critical element in aircraft design, evaluating levels based on MIL-STD-1797 or GJB standards, providing performance requirements for control law design. Multi-dimensional evaluation through eigenvalue analysis, frequency domain response and time domain simulation.
• Perform eigenvalue analysis using MATLAB/Simulink, calculate damping ratios and natural frequencies of short-period, phugoid, roll, yaw modes
• Plot Bode diagrams and root locus, analyze stability margins, determine phase margin and gain margin
• Rate flying qualities levels according to MIL-STD-1797B standard, distinguish Level 1/2/3 flying qualities
Deliverable: Flying qualities analysis report (including eigenvalue table, modal parameters, Bode plots, root locus, quality level assessment) | Quality standard: Analysis method compliant with standards, accurate modal parameters, correct quality rating
Step 3
Wing Planform Design
This step performs flight control law design, enabling the closed-loop system to meet desired flying qualities specifications. Control law design is the core of flight control systems, using classical PID or modern control theory methods, improving system dynamic characteristics through feedback compensation. Robustness, disturbance rejection and engineering implementability must be considered.
• Design PID controller using root locus or frequency domain compensation methods, determine proportional, integral, derivative gain parameters
• Design stability augmentation system and control augmentation system, introduce pitch rate, normal acceleration feedback signals to improve damping
• Apply LQR or H∞ methods for modern control law design, adjust performance and robustness balance through weight matrices
Deliverable: Control law design report (including controller structure, parameter tuning process, stability margins, robustness analysis) | Quality standard: Reasonable control law structure, optimized parameters, meeting flying qualities specs, sufficient stability margins
Step 4
Numerical Computation
This step uses simulation software for control law simulation verification, comprehensively testing system performance in a digital environment. Simulation is an essential means in modern aircraft design, allowing verification of system response under various flight conditions without physical hardware, reducing flight test risk. Multi-dimensional control effect verification through time and frequency domain analysis.
• Build closed-loop simulation model in MATLAB/Simulink, set typical input signals such as step, pulse and sine
• Conduct multi-condition simulation verification, including system response under cruise, takeoff, landing and other flight states
• Add sensor noise, aerodynamic parameter perturbations and external disturbances to verify system robustness and disturbance rejection
Deliverable: Simulation verification report (including simulation model, time domain response curves, frequency domain characteristics, robustness test results) | Quality standard: Accurate simulation model, comprehensive condition coverage, reasonable response curves, qualified robustness
Step 5
Optimization and Report
This step is a critical element in aerospace engineering projects, accomplishing specific task objectives through professional methods and tools. Aerospace engineering emphasizes safety, reliability and precision, requiring rigorous theoretical derivation and sufficient verification at every step. Industry standard methods and professional software tools are used to ensure result accuracy and engineering practicality.
• Clarify task objectives and technical specifications, develop detailed implementation plan and technical route based on aerospace related standards
• Use professional software tools (MATLAB/ANSYS/Fluent/CATIA, etc.) for modeling, calculation or simulation analysis
• Compare and validate with test data or literature results, ensuring results are reliable and meet engineering requirements
Deliverable: Professional technical report (including method description, calculation process, result data, validation comparison, conclusions and suggestions) | Quality standard: Scientific and standard method, accurate and reliable data, evidence-based conclusions, meeting engineering standards