STITCH
Full-Envelope Stitched Simulation from Individual Linear Models and Trim Data
Figure 1: STITCH Version 2.0
STITCH 2.0 is Here! – New Features & Improvements
[August 2025] The STITCH development team is happy to announce the release of STITCH 2.0! This major update is the culmination of three years of research and development work and represents a significant improvement over version 1.1.
Notable advancements include:
Command Line Interface (CLI) functionality
In addition to the Graphical User Interface (GUI), STITCH 2.0 introduces a fully integrated Command Line Interface (CLI) that allows scripting STITCH functionality using MATLAB code. The CLI streamlines the development of STITCH simulation models by increasing efficiency and repeatability. Users can leverage a provided MATLAB script – mirroring the Solution Project walkthrough – as a starting point for customized workflows. CLI functions also include help documentation.
Implicit Derivatives Equalization and Assessment of Linearization (IDEAL) utility
Three years of research focused on improving the correlation between the implicit and explicit speed derivatives in STITCH has led to the development of the IDEAL utility. IDEAL enhances the fidelity of full flight-envelope STITCH simulation models and enables direct assessment of linearized STITCH model dynamics, streamlining integration with flight control design. IDEAL can also be used to fill in trim data for unmeasured states, such as rotor flapping states or other higher-order states.
Plus, various additions and refinements including:
- Export linearized STITCH model state-space sys's to a .mat file (e.g., for easy import to CONDUIT)
- Many user experience improvements
- Professional-grade User's Guide
- Support up through MATLAB R2025a
About STITCH
Accelerate your flight-dynamics simulation development with STITCH. This innovative software allows you to quickly build and verify high-fidelity, full-envelope simulation models from existing point models and trim data – without requiring specialized modeling skills. STITCH automatically generates a Simulink block and data files, streamlining the process for continuous, real-time piloted simulation and hardware-in-the-loop flight control testing, leading to faster design cycles and more efficient analysis.
Background
Model stitching is the technique of combining or “stitching” together individual linear models and trim data for discrete flight conditions to produce a continuous, full flight-envelope simulation model. In this technique, the stability and control derivatives and trim data for each discrete point model are stored as a function of key parameters such as airspeed and altitude. The look-up of trim and derivatives is combined with nonlinear equations of motion and nonlinear gravitational force equations to produce a continuous, quasi-nonlinear stitched simulation model.
Key Features
- Intuitive user interface to guide the user through the entire process of generating a stitched model
- Support for rotorcraft and fixed-wing aircraft
- Processing of raw flight-test data
- Automated generation/verification of Simulink stitched model
- Accurate extrapolation to off-nominal conditions (speed, weight, center of gravity, inertia, altitude)
- Direct access to CIFER® database to import identified point models for stitched model generation
- Interactive plotting utilities
Figure 2: Project Setup
Figure 3: Anchor Point Models and Trim Data
Figure 4: Model Linearization Verification
Additional Information
Sales & Other Inquiries Contact
San José State University Research Foundation
flight-control-sta@sjsu.edu
