英文摘要 | The research on three-dimensional (3D) terrain detection is studied for essential technologies for detecting 3D information and building 3D representation of unstructured terrain safely, efficiently and accurately in a large area, which will support valuable applications of various fields, such as planetary exploration, urban model construction, underground mine mapping, etc. In this paper, started with current approaches to 3D terrain detection, their advantages and limitations are presented. The combination of a small unmanned helicopter with onboard sensors and equipment is considered as a suitable and feasible platform for 3D terrain detection. Based on standards for hardware selection, onboard hardware is chosen to provide 3D information of detected terrain and the hardware system is demonstrated. Several experiments are carried out in the real world by integrating algorithms into the platform and 3D terrain detection task is finally achieved. Firstly, the features of unstructured terrain are described. The conception, significance and applications of 3D terrain detection are introduced. Current approaches to terrain detection are reviewed. Our approach to terrain detection by integrating a small unmanned helicopter with Global Positioning System (GPS) and others sensors and equipment is presented. The background and the structure of this thesis are also addressed. Secondly, the aerial carrier-Unmanned Aerial Vehicle (UAV) and the key technology-GPS of 3D terrain detection are introduced. UAVs’ definition, classification and world-wide development are narrated. Especially, the assortment, the mechanism, flying modes and applications of model helicopters are expounded. The overwhelming advantages of applying a small unmanned helicopter into terrain detection are presented. The research development and main research directions in the field of model helicopters domestic and overseas are reviewed. What’s more, as a navigation system, GPS is introduced in detail, including its evolution, system architecture, localization principle and specific application in the research of 3D terrain detection. Thirdly, factors taken into account when selecting and designing hardware system are presented. Based on selection standards, the small unmanned helicopter, GPS equipment, distance laser sensor and embedded system with ARM 9 are chosen. The hardware system for 3D terrain detection is established and the hardware integration is described. Fourthly, the software framework for 3D terrain detection is designed. The onboard software based upon the embedded system is developed, aiming at automatic survey and data storage of the distance laser sensor. Combined with the software for communication between GPS receivers and palm computers and the post-processing software, data sampling and data processing are realized. |
修改评论