Nonlinear closed loop optimal control: A modified state-dependent Riccati equation

作者：Nekoo S Rafee^*

来源：ISA Transactions, 2013, 52(2): 285-290.

DOI：10.1016/j.isatra.2012.10.005

• SDRE
• Online control update
• Power series approximation
• Obstacle avoidance

The state-dependent Riccati equation (SDRE), as a controller, has been introduced and implemented since the 90s. In this article, the other aspects of this controller are declared which shows the capability of this technique. First, a general case which has control nonlinearities and time varying weighting matrix Q is solved with three approaches: exact solution (ES), online control update (OCU) and power series approximation (PSA). The proposed PSA in this paper is able to deal with time varying or state-dependent Q in nonlinear systems. As a result of having the solution of nonlinear systems with complex Q containing constraints, using OCU and proposed PSA, a method is introduced to prevent the collision of an end-effector of a robot and an obstacle which shows the adaptability of the SDRE controller. Two examples to support the idea are presented and conferred. Supplementing constraints to the SDRE via matrix Q this approach is named a modified SDRE.

• 出版日期2013-3