Dragonfly Model Validation Using System Identification of a Surrogate Vehicle

NASA's Dragonfly mission will use an autonomous uncrewed aerial vehicle to explore Saturn's largest moon, Titan. Designing a rotorcraft for that uncertain environment presents a unique challenge. The objective of the flight dynamics model validation effort is to ensure that the models used in the primary Dragonfly simulation are representative of the lander's flight on Titan. Because the Titan vehicle is not designed to fly on Earth, we have built a surrogate vehicle, the Integrated Test Platform (ITP) and modeled it using the same processes as used for the Titan vehicle. In this way, we validate the processes used to inform the simulation and lend confidence to our prediction of dynamics on Titan. This paper describes the system identification of the low-speed dynamics of the ITP vehicle and the first quantitative comparison of dynamics between the flight test data and the simulation. Discrepancies were uncovered in the lateral and directional axes. System identification is an iterative process, and we present several ways to improve the quality of the data in flights planned for 2026.