Minitype digital sun sensor

Abstract

The invention relates to the micro-digital sun sensing device and belongs to the attitude sensing device technology field. The sensing device comprises the light inducting device, the image collecting module composed of the image sensor, the attaching circuit an the image collecting control circuit, the image processing and communicating module. The light inducting device is layer-superposing structure with the narrow-belt or neutral optical filter, the transmission base plate, the mask layer and the glistening-proof layer from up to down. The mask layer adopts the small-hole array structure with unequal space; the small-hole array structure opens the square holes with two sizes, and the small holes and the rows of the different space appear alternatively. The invention can reduce the noise of the imaging circuit system and the random measuring error, and reduces the size, the energy consumption of the sensing device.

Description

technical field [0001] The invention belongs to the technical field of attitude sensors in attitude measurement control systems on skin-type and nano-type satellites and micro-spacecraft. In particular, it relates to the structural design of the light introducer in the optical system of the solar sensor. Background technique [0002] Sun sensors are widely used in the attitude positioning systems of satellites and spacecraft, but for pico-satellites, nano-satellites and micro-spacecraft, traditional sun sensors cannot meet the requirements in terms of volume, quality and power consumption; in addition , in order to meet the requirements of large field of view and high precision of the attitude positioning system at the same time, multiple attitude sensors are usually used. The digital sun sensor with an array structure currently existing or under study uses a digital image sensor as a photodetector, and its structure includes a sensor window plate, a light introducer fixed ...

AI Technical Summary

Problems solved by technology

[0004] 1. The image discretization and filling rate of the digital image sensor will cause a deviation in the estimation of the center position of the bright spot, which will cause a large random measurement error and limit the improvement of measurement accuracy

[0005] 2. The size of the light-transmitting holes in the mask layer of the light introducer processed by mechanical technology is large, the number of arrays is small, and the size of the small holes is generally millimeter or sub-millimeter level, which cannot make the solar sensor meet the requirements of miniaturization and high precision. The light introducer can also be processed by the MEMS process of silicon substrate coating. The main process is: depositing multi-layer metal thin films (depositing multi-layer metal thin films on silicon substrates, such as: chromium film with a thickness of 590A and gold film with a thickness of 2000A) →Coating photoresist→Pre-baking→Exposure→Development→Film hardening→Corrosion→Removal of glue, the silicon substrate can only pass through light with a large wavelength, such as light with a wavelength greater than 1000nm. Therefore, this solar sensor is not only complicated in process but also Image sensors requiring selection of specific spectral ranges

[0006] 3. Due to the diffraction effect of the small hole array, adjacent bright spots will overlap at large angles, which makes the ordinary moment method invalid and limits the increase of the field of view.

Therefore, the array structure digital sun sensor is more complicated than the single-hole digital sun sensor algorithm. In order to reduce the size of the sensor, the image processing module is usually placed in the on-board computer, while the sun sensor is only responsible for outputting images, which has poor versatility.

[0008] Therefore, the existing solar sensors cannot meet the requirements of the development of satellites and spacecraft

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