Design And Implementation Of Formation Control Experimental System For Quad-Rotor Based On Optical And UWB Positioning

With the continuous development of modern control technology,the quadrotor has become more and more integrated into the lives of people in recent years.Featured with a simple structure and control flexibility,the quadrotor can autonomously hover,vertically take off and land,and has been widely used in both military and civilian fields.Due to the volume and load limit,a single quadrotor is weak at load capacity and information processing.Multi-quadrotors with flight formation can solve this problem.They can complete the tasks that cannot be completed by a single quadrotor,and have outstanding advantages.At present,most of the quadrotor formation control is still in the theoretical stage,so it is urgent to carry out relevant experimental research.In this paper,we select the quadrotor as the research object,build the experimental system of the quadrotor formation control,and realize the expandable and transplantable software system.Our aim is to provide a reliable experimental platform for the formation control of the quadrotor.The main work of this paper is as follows:Firstly,the functional design of the whole system is completed from the perspective of demand analysis and design goals of the formation control system.According to the different functions,the system is divided into five subsystems,and the information exchange between different subsystems is realized through communication devices.In order to make the formation control experimental system more flexible and extensible,this paper selects two kinds of positioning devices with different principles and application scope and two quadrotors with different parameters and motion performance.This paper designs a layered software structure based on ROS,and completes the design and implementation of the hardware and software platform of the system.Secondly,this paper considers the quadrotor as a rigid body.Based on the Newton-Euler method,the dynamic model of the quadrotor is established without considering the interference.The design of the position and attitude controller of the quadrotor is given by the classical PID control algorithm.Then a trajectory tracking controller based on feedforward speed compensation is proposed.The flight verification is carried out in the formation control experimental sy stem,and the stable control of a single quadrotor is achieved.Finally,this paper discusses the experimental verification of the autonomous formation of the quadrotor.We transform the established dynamic model into a dual integrator model by nonlinear transformation,and design the centralized and distributed formation controllers respectively.Due to the deviation of the UWB positioning system,it is difficult to measure the flight speed of the quadrotor accurately.In this paper,we design a dimension estimation observer to estimate the speed.The formation algorithm and physical experiments are implemented with ROS.The feasibility of the platform and the algorithm is verified by simulation and experiment.