Solution to Point-to-Point Steering Problem for Constrained Flat System by Changing the Flat Output

This article presents a solution to point-to-point steering problem for constrained flat system. Constraints arise from the physical formulation of the problem. The proposed approach is based on the replacement of the flat output of the system by the one with the range of possible values within the feasible set. This work analyses the system describing the motion of the four rotor mini-rotorcraft and proves the flatness of such a dynamic system. Author designed the dynamic feedback linearizing the system. The maneuver for a point-to-point steering problem is the following: the mini-rotorcraft moves in a corridor from takeoff, through the horizontal flight, around the corner and to the landing. Thus, its movement is restricted by the floor, ceiling and walls. The solution of such a complex point-topoint steering problem can be divided into several steps. The first step is the problem of a small height lift and its solution. Then the flat output of the system is changed in order to satisfy all the constraints. In the beginning of the second step the trajectory deviates insignificantly from the planned one. It happens because of the replacement of the flat output and switching the control. Other steps do not have any deviation. The article demonstrates the effectiveness of the proposed approach by showing the results of numerical simulation.

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