Design And Implementation Of HUD System On Reusable Software Mechanism

HUD system is short for Head Up Display system,which provides pilots with important data of the aircraft's flying status and its external environment.In benefit of the tremendous development of airborne software and electronic techniques,traditional display instruments are now replaced by embedded software on a large scale.In the mean time,due to close combination of military software and hardware,the exploitation of software are based on specific hardware,which leads to the situation that it is hard to realize software reusability.There is not too much difference between each individual aircraft in developing HUD system,however,repetition exploitation work has too much cost for researchers.Moreover,the whole progress has been delayed because of the repetition and its inconvenience for later project management and maintenance.To solve the situation mentioned above,Aeronautical Ratio Incorporation released ARINC Specification 661 in the beginning of this century,which greatly improved the flexibility and expansibility of HUD software by dividing the display system and user application.Research of this specification,however,is just in its beginning progress domestically.In this thesis,through study of software reuse mechanism and the new HUD structure presented by ARINC661 specification,and in combination with good portability of OpenGL,an HUD kernel software scheme which solves high coupling problems of system code is designed and realized.To start with,this thesis sets its focus on research of reusable HUD software structure and 2D clipping algorithms and their improvements.Then according to the demand analysis,this thesis raised an overall system scheme,completing the design of HUD core software structure and each individual function units.Upon the design discussed above,this thesis realized three main functions of the HUD kernel software: Definition files loader,Renderer and the communication system.Through definition files,the loader can receive portraying information defined by user,thus providing reference for other function units.The renderer depicts graphic information via capsulated Open GL interface and fulfill clipping operation using the improved clipping algorithm.The communication system allows the kernel software to motivate the renderer dynamically through communication command,capturing and responding accurately to requests from user during the whole time.Finally,a test case is designed to finish verification of the function and perform properties of the software.The result shows that the software designed in this thesis is feasible,and it helps to break down the dilemma that different models' HUD should be redeveloped,reduce the cost of developing and modifying the overall software,making great contribution to domestic airborne HUD software development.