STITCH

Full-Envelope Stitched Simulation from Individual Linear Models and Trim Data

Full-Envelope Stitched Simulation from Individual Linear Models and Trim Data

Figure 1: STITCH Version 1.1

STITCH is a comprehensive software capability that allows a non-expert to create and verify a stitched simulation model. This tool features a user interface and MATLAB-based infrastructure in which the user supplies point linear models and trim data, and STITCH generates a Simulink stitched model block and corresponding MATLAB data 铿乴e. The stitched simulation model can then be used for continuous, real-time full-envelope piloted simulation or 铿俰ght control evaluation within hardware-in-the-loop simulation.

Background

Model stitching is the technique of combining or 鈥渟titching鈥� together individual linear models and trim data for discrete 铿俰ght conditions to produce a continuous, full 铿俰ght-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 铿亁ed-wing aircraft
  • Processing of raw 铿俰ght-test data
  • Automated generation/veri铿乧ation of Simulink stitched model
  • Accurate extrapolation to off-nominal conditions (speed, weight, center of gravity, inertia, altitude)
  • Direct access to CIFER庐 database to import identi铿乪d point models for stitched model generation
  • Interactive plotting utilities
  • Help documentation via links on each screen

STITCH version 1.1 is available as of March 2022

Fig. 1: Project setup

Figure 2: Project Setup

Fig. 2: Anchor point models and trim data

Figure 3: Anchor Point Models and Trim Data

Fig. 3: Stitched model linearization veri铿乧ation 

Figure 4: Stitched Model Linearization Veri铿乧ation 

 

SALES & OTHER INQUIRIES CONTACT
San Jos茅 State University Research Foundation 
flight-control-sta@sjsu.edu

References

  1. Tobias, E. L. and Tischler, M. B., 鈥淎 Model Stitching Architecture for Continuous Full Flight-Envelope Simulation of Fixed-Wing Aircraft and Rotorcraft from Discrete-Point Linear Models,鈥� U.S. Army AMRDEC Special Report RDMR-AF-16-01, April 2016.
  2. Tobias, E., Sanders, F., Tischler, M., 鈥淔ull-Envelope Stitched Simulation Model of a Quadcopter Using STITCH,鈥� American Helicopter Society 74th Annual Forum, Phoenix, AZ, May 2018.