A Comparative Study of INDI and NDI with Nonlinear Disturbance Observer for Aerial Robotics
Provides practical guidance for choosing between incremental and observer-based inversion strategies in aerial robotics.
This paper compares INDI and NDI+NDO for aerial robots via simulations, finding INDI more robust under model mismatch and combined stress, while NDI+NDO matches nominal performance but is more sensitive to non-ideal conditions.
This work presents a simulation-based comparative robustness analysis of Incremental Nonlinear Dynamic Inversion (INDI) and Nonlinear Dynamic Inversion augmented with a nonlinear disturbance observer (NDI+NDO) for fully actuated aerial robots. A systematic simulation campaign across representative operating scenarios is conducted, where we compare tracking performance, robustness, control effort, under parametric variations, external disturbances, and measurement noise. Results show that INDI demonstrates stronger robustness in several model-mismatch and combined-stress cases, while NDI+NDO primarily matches nominal performance but exhibits greater sensitivity under several non-ideal conditions. These findings provide practical guidance on the relative strengths and limitations of incremental and observer-based inversion strategies for aerial robotic applications.