Enhanced Field of View
One of the primary benefits of using two or more projector channels in a simulation, particularly simulators, is the ability to achieve a wide field of view (FOV). In immersive environments like the Cobra180 Venom dome, achieving a 180° horizontal FOV is critical for creating a realistic and immersive experience for the pilot.
A single projector or channel often has limitations in the maximum FOV it can render without significant distortion or loss of image quality. Typically, projectors can cover around 90° to 120° horizontally. To achieve a full 180° horizontal FOV, at least two frustums (projected views) are required. Each frustum covers a portion of the FOV, and when combined, they create a seamless wide-angle view that closely matches human vision, crucial for realistic training scenarios.
Improved Image Quality and Resolution
By using multiple channels, each projector can cover a smaller section of the overall FOV, allowing for higher resolution and better image quality within that section. This means that the visuals within each frustum can be rendered with more detail, providing clearer and more realistic images. This is especially important within flight simulation, where pilots rely on high-resolution visuals to accurately interpret the environment and respond to simulated conditions.
Reduced Distortion and Seamless Blending
When attempting to stretch a single projector to cover a wide FOV, significant distortion can occur, particularly at the edges of the image. This distortion can detract from the realism of the simulation and make it difficult for pilots to accurately gauge distances and spatial relationships. Using multiple channels allows for better control over image geometry and reduces distortion by dividing the FOV into more manageable sections.
Advanced blending technologies, such as those provided by Scalable Display Technologies, ensure that the images from the projectors are seamlessly combined. This blending process involves adjusting the overlap between the images to create a smooth transition with no visible seams, resulting in a cohesive and immersive visual experience.
Established in 2004, Scalable is the original inventor and patent holder of camera-based automatic warp and blend technology and develops software that automatically converges the outputs of multiple projectors into a single seamless display. Ideal for virtually any application, Scalable’s software works on flat, curved domes and completely custom screen shapes. There are no limits to the size or resolution of displays created utilising Scalable’s software technology. Their automatic warp and blend capabilities have allowed Cobra Simulation to create a more robust solution for its clients.
Issues with Camera Viewpoints and Frustum Rendering
Camera Viewpoint in Rendered Environments
In a rendered environment, the camera viewpoint determines what is visible on the screen. The viewpoint is essentially the position and orientation of the virtual camera within the 3D scene. In simulation, especially flight simulation, the camera viewpoint must accurately mimic the pilot's perspective to create a realistic training environment.
Issues arise when the FOV required by the simulation exceeds the capabilities of a single camera viewpoint or projector. A single viewpoint typically provides a conical frustum, which can be insufficient for wide-angle views. The FOV of this frustum is limited by the aspect ratio and resolution of the projection system, leading to potential blind spots or areas of low detail at the periphery of the view.
Maximum Field of View Frustum
The maximum FOV frustum that a single projector can achieve is constrained by the projector's optics and the screen's curvature. Cobra uses the OmniFocus fish-eye optics to expand the throw of the image. For a 180° horizontal FOV, the frustum needs to cover a hemispherical view, which is challenging for a single projector. This is why multiple frustums are necessary.
Each frustum is a geometric representation of the visible space within the camera's view, defined by the near and far clipping planes and the angles of the view pyramid. To cover a 180° horizontal FOV, two frustums are typically arranged side by side, each covering approximately 90° to 100°. This arrangement ensures that the entire 180° view is covered without significant distortion or loss of detail at the edges.
Application in Flight Simulation
In flight simulation, rendering a perspective view for the pilot is crucial. The pilot must be able to see not only directly ahead but also to the sides, simulating the natural range of vision experienced in a real cockpit. This wide-angle view is essential for tasks such as landing, taking off, and navigating complex airspace.
Using two channels with blended frustums allows the simulation to provide a realistic and immersive visual environment. Each channel renders a part of the scene from the pilot's perspective, ensuring that the entire 180° horizontal FOV is covered. The blending process ensures that the transition between the frustums is seamless, creating a continuous and uninterrupted view.
This setup enhances situational awareness and improves the training effectiveness by providing a realistic and immersive environment. Pilots can practice manoeuvres and procedures as they would in a real aircraft, with the visual cues and peripheral vision that are critical for accurate and safe flying.
Conclusion
The use of two channels in simulation, particularly for applications within the Cobra180 Venom dome, offers significant benefits in terms of enhanced FOV, improved image quality, and reduced distortion. Addressing the issues associated with camera viewpoints and frustum rendering, this approach ensures that simulations are realistic, immersive, and effective for training purposes.
By leveraging the advanced technologies from Cobra Simulation and Scalable Display Technologies, the simulation industry can provide unparalleled training solutions that meet the highest standards of realism and functionality.