STITCH is a new software capability that allows a non-expert to create and verify a stitched simulation model. This tool features a GUI 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 file. The stitched simulation model can then be used for continuous, full-envelope piloted simulation or flight control evaluation within hardware-in-the-loop simulation.
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 .
STITCH version 1.0 is available as of March 2019.
Fig. 1: Project set up
Fig. 2: Anchor point models and trim data
Fig 3. Stitched model linearization verification