Design of localizer capture and track modes for a lateral autopilot using H-infinity synthesis

Results are presented of a design exercise in which the most recent developments in H-infinity synthesis theory were applied to the problem of designing a lateral autopilot for a typical transport airplane. The bulk of the engineering effort in applying these results was in the formulation of an appropriate synthesis model. Important aspects of this process are presented. The linear controller design was done using H-infinity synthesis theory. The linear design was suitably modified to satisfy some of the performance constraints. Results of linear analysis and simulation of the final nonlinear controllers are presented.<>