Four-rotor aircraft finite time control method based on exponential enhancement type constant speed approaching law and fast terminal sliding mode surface

Abstract

The invention relates to a four-rotor aircraft finite time control method based on an exponential enhancement type constant speed approaching law and a fast terminal sliding mode surface. The method includes the following steps that: step 1, a transfer matrix from a four-rotor aircraft-based aircraft body coordinate system to an earth-based inertia coordinate system is determined; step 2, a four-rotor aircraft dynamic model is analyzed according to Newton-Euler formula; and step 3, a tracking error is calculated, a controller is designed according to the fast terminal sliding mode surface andthe first-order derivative thereof. According to the method of the invention, the exponential enhancement type constant speed approaching law sliding mode control and fast terminal sliding mode control are used in combination according to a four-rotor aircraft, therefore, approaching speed can be increased when a system is far away from a sliding mode surface, buffeting can be decreased, the rapidity and robustness of the system can be improved, fast and stable control can be realized, the finite time control of the tracking error can be realized, and a problem that a tracking error can be approximately 0 provided that the time tends to be infinite in a traditional sliding mode surface can be solved.

Description

technical field [0001] The invention relates to a finite-time control method for a quadrotor aircraft based on an exponentially enhanced constant-velocity approach law and a fast terminal sliding mode surface. Background technique [0002] Due to the characteristics of simple structure, strong maneuverability and unique flight mode, quadrotor aircraft has attracted extensive attention from scholars and scientific research institutions at home and abroad, and has quickly become one of the hot spots in international research. Compared with fixed-wing aircraft, rotorcraft can lift vertically, has low environmental requirements, does not need a runway, reduces costs, and has huge commercial value. The development of aircraft has made many dangerous high-altitude operations easy and safe, deterring other countries in military aspects, and greatly increasing work efficiency in civilian aspects. Quadrotors are highly flexible, can achieve rapid transitions of motion and hovering a...

AI Technical Summary

Problems solved by technology

[0004] In order to overcome the problem that the traditional sliding mode surface cannot realize finite time control and further accelerate the approaching speed of the reaching law and reduce chattering, the present invention adopts fast terminal sliding mode control and an exponentially enhanced constant-velocity approaching law, through The idea of ​​switching control avoids the singularity problem, accelerates the approach speed of the system to the sliding mode surface, reduces chattering, and realizes limited time control

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