Path planning and shimmy damping control method of four-rotor variable-rope-length hanging system

Abstract

The invention discloses a path planning and shimmy damping control method for a four-rotor variable-rope-length hanging system. The method comprises the following steps: establishing a mathematical model of four rotors and a swinging model of a hung load; based on the established model, constraining the states of the four rotors and the load, calculating parameters of a spline curve according to constraint conditions, and acquiring a planned path; according to the obtained planned path, acquiring the minimum transportation time meeting the swing angle constraint condition through a bisection method; and by adopting a cascade control method based on integral backstepping and tracking the planned path, realizing accurate positioning of the load and swing angle suppression of the load, and sending the load to a preset position within the shortest time. According to the method disclosed by the invention, the whole hanging system can reach an expected position from an initial position in the shortest time by planning a proper planar motion track, and meanwhile, the swing angle of the load is kept to be limited in a relatively small range so that the transportation efficiency is improved, and the transportation safety is ensured.

Description

technical field [0001] The invention relates to a four-rotor control method, in particular to a path planning and swing reduction control method of a four-rotor variable rope length suspension system. Background technique [0002] In recent years, quadrotor suspension controls have become a hot topic of research and are widely used in business and science. Generally, manipulators are mainly divided into four types: grippers, manipulators, cables and others, and different manipulators are suitable for different application scenarios. The single-degree-of-freedom gripper is the most widely used manipulation device, which is mounted directly on or under the fuselage of the quadrotor UAV. This manipulation device has three advantages: (1) it is easy to manufacture, (2) it is convenient to model and control, and (3) it is relatively cheap to manufacture. The manipulator is mainly composed of two parts: one or more multi-degree-of-freedom arms attached to the drone body and a gr...

AI Technical Summary

Problems solved by technology

Active control is to analyze the possibility of target deviation in advance and take corresponding protective measures to achieve the target. Common control methods include optimal control and input shaping, but optimal control is more dependent on the accuracy of model establishment. For a nonlinear, strongly coupled quadrotor suspension system, it is still difficult to establish a very accurate model

The input shaping technology does not have high requirements on the accuracy of the system model, but it needs to accurately predict the swing characteristics of the load, so the robustness to external disturbances is not high

Passive control is to monitor the system in real time, process the speed and acceleration information output by the system, and send the feedback to the input terminal of the controller to control the deviation from the input terminal to achieve the goal. The most common ones are PID control and self-adaptive control, etc., but the above methods only produce more obvious control effects when the swing angle is too large, and the whole adjustment process takes a long time

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