Hyper-Hemispherical Dome for 360-Degree IR Coverage
Solution Overview
Problem
Existing infrared countermeasure systems with less than 180-degree hemispherical domes require multiple installations to achieve full spherical coverage, leaving blind spots and being prone to fabrication challenges with durable materials like sapphire and ALON, which limits their effectiveness against incoming threats.
Innovation Solution
A single-piece hyper-hemispherical dome with a look angle greater than 180 degrees, comprising a hemispherical region and a truncated-hemispherical region with complementary geometry, providing a continuous convex outer surface and concave inner surface, fabricated from materials like sapphire or ALON, allowing for seamless optical performance and enhanced threat detection.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If multiple less than 180-degree hemispherical domes are installed to achieve full spherical coverage, then coverage completeness is improved, but system complexity and number of components increase
Solution Approach 1:
The dome is segmented into two distinct regions: a hemispherical region spanning 180 degrees and a truncated-hemispherical region extending beyond the hemisphere to provide additional coverage. This segmentation allows each region to serve a specific optical coverage function while together they achieve greater than 180-degree total coverage from a single dome unit.
Solution Approach 2:
The design transitions from a standard hemisphere (180-degree coverage) to a hyper-hemispherical shape that extends into an additional dimensional space. The truncated-hemispherical region adds vertical extension beyond the traditional hemispherical boundary, enabling the single dome to cover angles greater than 180 degrees and eliminate the need for multiple dome installations.
2Ease of manufacture
If bonded hyper-hemispherical domes made of multiple pieces are fabricated, then manufacturing feasibility is improved, but optical performance deteriorates due to bonded seams
Solution Approach 1:
The hemispherical region and truncated-hemispherical region are merged into a single unitary dome structure fabricated from one continuous piece of material. This eliminates the bonded seams that would otherwise interfere with optical performance, while the internal geometric transition between the two regions maintains manufacturing feasibility through precise molding or forming processes.
Solution Approach 2:
The dome is fabricated from advanced optical materials such as sapphire or ALON that possess both the required mechanical strength and infrared optical transparency. These composite material properties enable the creation of a complex hyper-hemispherical shape in a single piece that would be difficult with conventional materials, simultaneously achieving manufacturing feasibility and superior optical performance.
3Reliability
If a single-piece hyper-hemispherical dome is fabricated from sapphire or ALON, then durability and optical quality are improved, but manufacturing difficulty increases
Solution Approach 1:
The complex hyper-hemispherical shape is predetermined in the mold or blank before the forming process begins. By preparing the precise geometric configuration in advance through computer-aided design and mold fabrication, the subsequent forming process can efficiently create the complex shape from a single piece of sapphire or ALON without requiring difficult post-processing or assembly operations.
Solution Approach 2:
The manufacturing process utilizes controlled changes in temperature, pressure, and material state to transform the raw sapphire or ALON material into the final hyper-hemispherical dome. By carefully controlling these parameters during forming or sintering, the process achieves the complex geometry with high precision while maintaining the material's superior durability and optical properties.
Data Source
AI summary
A counter measure system is provided having a unitary infrared transparent dome including a look angle greater than 180. The dome has two hemispherical regions, with a second region having a truncated bottom end defining an opening to a central cavity inside which electro-optical elements are disposed. The electro-optical elements can view outward through the dome at the look angle. The second region on the dome has a complementary curvature as the first region by continuing a similar radius beyond a transverse horizontal axis or equator. The dome is mounted to a base, which also may be referred to as a bezel. The base defines a rabbet extending circumferentially about the base imaginary center defining an aperture. The base and the dome are formed from different materials but have equivalent coefficients of thermal expansion. In one embodiment the dome if formed from sapphire and the base is titanium.