This work considers the task of accurate in-air localization for multiple unmanned or autonomous aerial vehicles flying in close formation. The paper describes our experimental setup using two small UAVs and the details of the localization algorithm. The algorithm was implemented on two low-cost, electric powered, remote control aircraft with wing spans of approximately 2 meters. Our control software, running on an onboard x86 CPU, uses LQG control (an LQR controller coupled with an EKF state estimator) and a linearized state space model to control both aircraft to fly synchronized circles. In addition to its control system, the lead aircraft is outfitted with a known pattern of high-intensity LED lights. The trailing aircraft captures images of these LEDs with a camera and uses the Orthogonal Iteration computer vision algorithm to determine the relative position and orientation of the trailing aircraft with respect to the lead aircraft at 25Hz. The entire process is carried-out in real-time with both vehicles flying autonomously. We note that the camera based system is used for localization, but not yet for closed-loop control. Although, an absolute quantification of the error for the in-air localization system is difficult as we do not have ground truth positioning data during flight testing, our simulation results analysis and indoor measurements suggest that we can achieve localization accuracy on the order of 10 cm (5% wingspan) when the UAVs are separated by a distance of about 10 meters (5 spans).
{"title":"Camera Based Localization for Autonomous UAV Formation Flight","authors":"Z. Mahboubi, Zico Kolter, Tao Wang, G. Bower","doi":"10.2514/6.2011-1658","DOIUrl":"https://doi.org/10.2514/6.2011-1658","url":null,"abstract":"This work considers the task of accurate in-air localization for multiple unmanned or autonomous aerial vehicles flying in close formation. The paper describes our experimental setup using two small UAVs and the details of the localization algorithm. The algorithm was implemented on two low-cost, electric powered, remote control aircraft with wing spans of approximately 2 meters. Our control software, running on an onboard x86 CPU, uses LQG control (an LQR controller coupled with an EKF state estimator) and a linearized state space model to control both aircraft to fly synchronized circles. In addition to its control system, the lead aircraft is outfitted with a known pattern of high-intensity LED lights. The trailing aircraft captures images of these LEDs with a camera and uses the Orthogonal Iteration computer vision algorithm to determine the relative position and orientation of the trailing aircraft with respect to the lead aircraft at 25Hz. The entire process is carried-out in real-time with both vehicles flying autonomously. We note that the camera based system is used for localization, but not yet for closed-loop control. Although, an absolute quantification of the error for the in-air localization system is difficult as we do not have ground truth positioning data during flight testing, our simulation results analysis and indoor measurements suggest that we can achieve localization accuracy on the order of 10 cm (5% wingspan) when the UAVs are separated by a distance of about 10 meters (5 spans).","PeriodicalId":269486,"journal":{"name":"Infotech@Aerospace 2011","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126686714","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Phillip Italiano, Cody Lafountain, Kelly Cohen, S. Abdallah
The aircraft industry, military, and NASA mainly rely on the Stewart platform design, a fixed ground-based flight simulator, for the preliminary stages of pilot training and the testing of new aircraft. These systems are large, and expensive to maintain and repair. In this effort, we propose a Tensegrity based structural concept as the basis for a unique and effective flight simulator. Tensegrity structures are systems of tensile cables and compressive members. This structure has a high precision of control, is lightweight, and deployable. At the University of Cincinnati, preliminary Tensegrity models have been constructed to test our understanding of a dynamic nature of the system and to provide physical models to work with. Some of these models were constructed as static models in order to gain an understanding of construction methods. Another model was constructed as a dynamic model, consisting of small pulleys and cables, to simulate the basic operations of a flight simulator. Nomenclature θ = angular velocity about x-axis φ = angular velocity about y-axis ψ = angular velocity about z-axis I. Introduction HE main objective of this project was to use SIM Mechanics® to investigate the structural properties of a Tensegrity flight simulator. In order to accomplish this goal, it was necessary to develop algorithms that determine the necessary cable length variations to establish stable dynamic Tensegrity structures. These structures were then manipulated to simulate the perturbations required to accurately simulate the characteristics of an aircraft. Once the range of motion for a Tensegrity structure of this type was determined, the structures were subjected to external forces to determine the dynamic responses. This system will be dynamically controlled and respond in real time to the pilot's commands. The reasoning for this project is to design a flight simulator that could be used for micro UAV's in wind tunnels and the replacement of conventional high-energy flight simulators.
{"title":"Tensegrity Structure as the Control Base of a Flight Simulator","authors":"Phillip Italiano, Cody Lafountain, Kelly Cohen, S. Abdallah","doi":"10.2514/6.2011-1467","DOIUrl":"https://doi.org/10.2514/6.2011-1467","url":null,"abstract":"The aircraft industry, military, and NASA mainly rely on the Stewart platform design, a fixed ground-based flight simulator, for the preliminary stages of pilot training and the testing of new aircraft. These systems are large, and expensive to maintain and repair. In this effort, we propose a Tensegrity based structural concept as the basis for a unique and effective flight simulator. Tensegrity structures are systems of tensile cables and compressive members. This structure has a high precision of control, is lightweight, and deployable. At the University of Cincinnati, preliminary Tensegrity models have been constructed to test our understanding of a dynamic nature of the system and to provide physical models to work with. Some of these models were constructed as static models in order to gain an understanding of construction methods. Another model was constructed as a dynamic model, consisting of small pulleys and cables, to simulate the basic operations of a flight simulator. Nomenclature θ = angular velocity about x-axis φ = angular velocity about y-axis ψ = angular velocity about z-axis I. Introduction HE main objective of this project was to use SIM Mechanics® to investigate the structural properties of a Tensegrity flight simulator. In order to accomplish this goal, it was necessary to develop algorithms that determine the necessary cable length variations to establish stable dynamic Tensegrity structures. These structures were then manipulated to simulate the perturbations required to accurately simulate the characteristics of an aircraft. Once the range of motion for a Tensegrity structure of this type was determined, the structures were subjected to external forces to determine the dynamic responses. This system will be dynamically controlled and respond in real time to the pilot's commands. The reasoning for this project is to design a flight simulator that could be used for micro UAV's in wind tunnels and the replacement of conventional high-energy flight simulators.","PeriodicalId":269486,"journal":{"name":"Infotech@Aerospace 2011","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122000126","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：