Research has been done recently on automated steering systems for automobiles which would make hands-free driving possible. In the present research, it was shown both experimentally and by simulations that the use of linear quadratic (LQ) control improves lane tracking control performance. It was observed that LQ control improves tracking performance by working to separate yaw motion from lateral motion. It was found that both satisfactory steady-state characteristics and response could be obtained by suitably weighting lateral motion. The first part of this paper shows how the use of LQ control facilitates lane tracking along a straightway. The second half describes a method for enabling an automated vehicle to navigate curves. It is shown that detection of the vehicle's lateral deviation alone, without any feed-forward information about the road curvature or other conditions, is sufficient to secure stable cornering performance.
Abstract