Feedback Linearization-Based Guidance with Zero-Dynamics Correction for Guaranteed Interception

Researchers Alexander Dorsey and Ankit Goel have published a new paper on arXiv proposing a guidance law for nonlinear interception that addresses a fundamental limitation of input-output feedback linearization (IOL). In the engagement between a pursuer and an evader modeled with point-mass dynamics, baseline IOL regulates line-of-sight (LOS) angular rates but leaves the system's internal (zero) dynamics unconstrained. This can produce trajectories where LOS alignment occurs but the pursuer never reaches the evader. The authors introduce a correction term that actively forces range convergence, ensuring any LOS alignment corresponds to a closing trajectory. The method retains the computational simplicity and real-time implementability of feedback linearization while dramatically improving interception performance.

Extensive Monte Carlo simulations across a wide range of initial engagement geometries demonstrated the new guidance law's superiority. Compared to both the baseline IOL and classical proportional navigation, the proposed approach showed consistently reduced miss distances and higher overall reliability. The correction mechanism works without adding significant complexity, making it suitable for real-time autonomous systems. This work has direct implications for missile guidance, drone interception, and robotic pursuit-evasion scenarios where guaranteed convergence is critical. The simplicity of the algorithm also opens the door for deployment on resource-constrained platforms.