The Technology Of Synthetic Vision And Embedded Display Processing

One of the major causes for hazardous situations in aviation is the lack of a pilot’s situational awareness, common causes for degraded situational awareness are flights in degraded virtual environment (DVE), and low level flights, these conditions may cause the pilot to lose important visual cues thereby increasing workload and compromising flight safety and mission effectiveness. Synthetic Vision Systems and Enhanced Vision Systems (SVS/EVS) technologies have the potential to provide additional margins of safety for aircrew performance and enable operational improvements for low visibility operations in the terminal area environment with equivalent efficiency as visual operations. This dissertation is mainly concerned with the technology of synthetic vision and embedded display processing. The author’s major contributions are outlined as follows:First introduces the theoretical basis of synthetic vision, mainly details the applications of synthetic vision in enhanced situational awareness, including the concept, types of DVE and its effects on flight, also describes the details of symbol in synthetic vision. Then, DSP platform as well as DSP/BIOS have been intensive studied according to the system’s hardware implementation, and designs a multi-threading implementation scheme, which ensures the real-time characteristic of our system through a variety of thread priority and preemption strategy. After that, this paper puts forward a kind of method which can guarantees real-time characteristic and display effect of dynamic superposition to solve the key problems of dynamic symbols and multichannel video display, and also gives a deeply analysis and comparison with several kinds of multi-channel video scaling algorithm, according to the comparison results, the nearest neighbor sampling method is selected as the final multi-channel video scaling algorithm. The results show that these methods can well ensure dynamic symbols and multichannel video real-time performance and stability, the display effect is clear and has good recognition.According to the above technical implementation, this paper achieves six different synthetic vision modes with different flight missions based on the DSP hardware platform. In order to overcome the problem of synchronous display between flight symbols and outside scene of each display mode, scene display of each mode is implemented through software simulation in this paper, meanwhile, we use LAN multicast method to solve the synchronization problem between multi-channel video scenes. Eventually, the show effects of each mode are validated through overall presentations, the results indicate that display symbols and scene video of each mode all have excellent real-time and synchronizing performance.