Linear Quadratic Regulator

A Linear Quadratic Regulator (LQR) is a control strategy used to manage systems smoothly and efficiently. It calculates the best way to adjust inputs to a system—like steering a car or balancing a robot—so that it performs well while minimizing costs such as energy or effort. The "linear" part means the system's behavior responds proportionally to inputs, and the "quadratic" part refers to the way costs are measured, emphasizing larger errors or efforts more heavily. Overall, LQR helps devices maintain desired states with optimal, balanced control actions.