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Abstract We use a novel backstepping method to solve a stabilization problem for a nonlinear system with delayed sampled outputs that are not accurately measured. We provide an application to a system arising in vision‐based landing of airliners that includes coupling between the lateral and longitudinal dynamics, for which we provide performance guarantees in the presence of the delay, nonlinearity, and sampling. Our major contributions are (a) designs of lateral and longitudinal controls for our nonlinear model of an aircraft landing on an unequipped runway, (b) mathematical proofs that our controls ensure that the aircraft being modeled achieves desired alignment with the runway during its align phase, under sampling and delays that arise from image processing of visual information, and (c) comparative simulations exhibiting considerable improvement in control performance compared with previous methods that did not take the coupling of the dynamics or imprecise delayed sampled measurements into account. 

Summary We provide barrier Lyapunov functions for model reference adaptive control algorithms, allowing us to prove robustness in the input‐to‐state stability framework and to compute rates of exponential convergence of the tracking and parameter identification errors to zero. Our results ensure identification of all entries of the unknown weight and control effectiveness matrices. We provide easily checked sufficient conditions for our relaxed persistency of excitation conditions to hold. Our illustrative numerical example demonstrates the performance of the control methods.