Iterative State- and Control-Dependent Model Predictive Control: A Jacobian-Free Formulation for Constrained Nonlinear Systems

arXiv:2608.15322 2026 Dynamics 1 ideas extracted · analyzed Sep 1, 2026

What the math gives to ML

The paper's transferable asset is an exact, derivative-free pseudo-linearization of nonlinear dynamics, followed by repeated solution of structured linear-quadratic subproblems. Rather than differentiating a learned world model through a long horizon, a neural controller can construct secant-based state- and control-dependent matrices from function evaluations, freeze them along the current predicted trajectory, and solve a constrained quadratic planning problem. The contraction and terminal-cost arguments suggest a practical stopping rule and a way to retain stability when only a few planning iterations are affordable, although the guarantees require local regularity and may not hold for an unconstrained neural model.

Ideas from this paper

Unverified 2026

Jacobian-Free Secant MPC for Learned Dynamics

Use a learned transition model inside MPC without computing its Jacobian. At every planning iteration, construct coordinate-wise secant matrices from model evaluations, freeze those matrices along the current predicted trajectory, and solve a constrained linear-quadratic subproblem; then re-roll out the nonlinear model and repeat. This targets model-based RL settings where reverse-mode differentiation through hundreds of dynamics steps is expensive or numerically unstable.

Useful6/10
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Paper: Iterative State- and Control-Dependent Model Predictive Control: A Jacobian-Free Formulation for Constrained Nonlinear Systems arXiv:2608.15322