New asymmetry monitoring techniques: Effects on attitude control

The asymmetry limitation between left and right wing flap surfaces is one of the most severe requirements for the design of the actuation and control system. Each asymmetry exceeding a defined value must be detected and limited by appropriate monitoring devices equipped with a suitable software.In the design of a new flap control system the development of the asymmetry monitoring system plays a very important role and it is a very debated matter in industrial field. Nevertheless in scientific literature this topic is so neglected that, at the best of our knowledge, no paper dealing with the specific argument exists, except for the authors' works listed in the references.The currently used monitoring technique is based on the differential position control between left and right surfaces. Nevertheless in particularly severe conditions the above mentioned technique may be unable to prevent potentially critical asymmetries; in order to limit the above mentioned shortcomings, the authors proposed and developed some innovative monitoring techniques in previous papers. Their use generally reduces the asymmetry slightly, but in some cases it may have an unreliable behavior. In order to overcome the shortcomings of the previous models, in this work the authors develop and propose new different monitoring strategies and assess their positive effects on the maximum asymmetry following a torque tube failure.