Related Experiment Video
Updated: Aug 25, 2025
12:27
A Pipeline to Investigate the Structures and Signaling Pathways of Sphingosine 1-Phosphate Receptors
Published on: June 8, 2022
3.5K
ISSM-ELM - a guide star selection for a small-FOV star sensor based on the improved SSM and extreme learning machine
Applied Optics
|October 18, 2022
Summary
A new method combines the improved spherical spiral method (ISSM) and extreme learning machine (ELM) to create better guide star catalogs for small field-of-view (FOV) star sensors. This approach reduces storage needs and improves star distribution.
Area of Science:
- Astronomy and Astrophysics
- Space Science and Technology
- Computer Science and Engineering
Background:
- Accurate attitude determination and star map recognition are vital for star sensors.
- Existing guide star catalog methods are mature for large FOV sensors but face challenges with small FOV sensors, including large storage, uneven distribution, and voids.
- These challenges limit the effectiveness of small FOV star sensors in applications requiring precise navigation.
Purpose of the Study:
- To develop an efficient and effective method for constructing guide star catalogs specifically for small FOV star sensors.
- To address the limitations of existing methods, such as large storage capacity, uneven star distribution, and catalog voids.
- To enhance the overall quality and usability of guide star catalogs for small FOV star sensor applications.
Main Methods:
- The proposed method, ISSM-ELM, combines the improved spherical spiral method (ISSM) and extreme learning machine (ELM).
- ISSM is used for preliminary screening of guide stars based on star-diagonal distance, density, and magnitude relative to a spiral reference point.
- ELM is employed to supplement sparse areas and construct an integral guide star catalog.
Main Results:
- The ISSM-ELM method significantly reduces the storage capacity required for the guide star catalog.
- The method improves the uniformity and integrity of the star distribution within the catalog.
- An enhanced average brightness of guide stars is achieved, improving sensor performance.
Conclusions:
- The ISSM-ELM method offers a viable solution for constructing high-quality guide star catalogs for small FOV star sensors.
- This approach overcomes key limitations of previous methods, enhancing catalog efficiency and reliability.
- The improved catalog facilitates more accurate star map recognition and attitude determination in space applications.
Related Concept Videos
01:22Force Classification
1.4K
Forces play a crucial role in the study of physics and engineering. They are essential in describing the motion, behavior, and equilibrium of objects in the physical world. Forces can be classified based on their origin, type, and direction of action.
Contact and non-contact forces are two of the most widely used categories of forces. As the name suggests, contact forces require physical contact between two objects to act upon each other. Examples of contact forces include frictional,...
Contact and non-contact forces are two of the most widely used categories of forces. As the name suggests, contact forces require physical contact between two objects to act upon each other. Examples of contact forces include frictional,...
1.4K
01:31Classification of Systems-II
215
Continuous-time systems have continuous input and output signals, with time measured continuously. These systems are generally defined by differential or algebraic equations. For instance, in an RC circuit, the relationship between input and output voltage is expressed through a differential equation derived from Ohm's law and the capacitor relation,
215
02:16Light Acquisition
8.6K
In order to produce glucose, plants need to capture sufficient light energy. Many modern plants have evolved leaves specialized for light acquisition. Leaves can be only millimeters in width or tens of meters wide, depending on the environment. Due to competition for sunlight, evolution has driven the evolution of increasingly larger leaves and taller plants, to avoid shading by their neighbors with contaminant elaboration of root architecture and mechanisms to transport water and nutrients.
8.6K
01:16Confocal Fluorescence Microscopy
13.6K
Confocal microscopy is an advanced microscopic technique. The prime advantage of the confocal microscope over other microscopy techniques is its ability to block the out-of-focus light from the illuminated samples using pinholes. It is widely used with fluorescence optics to obtain high-resolution, sharp contrast images. Unlike optical microscopes, confocal microscopes use a focused beam of light laser to scan the entire sample surface at different z-planes. These microscopes are, therefore,...
13.6K