Error correction method and device for digital sun sensor

Abstract

The invention discloses an error correction method for a digital sun sensor. The method comprises the following steps of: 1, determining a proportional correction factor of a theoretical measured value and an actual measured value of a distance from a projection center of a speckle produced by a light introducer on an image sensor to an imaging point during vertical incidence of sunshine; 2, establishing an iterative equation; and 3, performing iterative computation to correct errors, selecting a measured value of a sunshine incident angle as an initial angle of iteration, converging to obtain the value of the angle so as to solve the correction factor in the step 1, and finally correcting the measured value according to the formula of the first step so as to obtain the theoretical measured value. The invention also provides a digital sun sensor based on the method, which can quickly and accurately correct errors and has resolution of 0.02 degree and two axial vision angles of 120 degrees. Thus, power consumption is greatly reduced, data refresh rate is increased, cost is reduced, and high-accuracy solar angle measurement in a large vision angle range is realized.

Description

technical field [0001] The invention belongs to the field of attitude sensors, and relates to an attitude measurement control system on a spacecraft, in particular to an error correction iteration method and device for a digital sun sensor. Background technique [0002] The basic function of the sun sensor is to obtain the orientation information of the sun vector in the star coordinate system fixedly connected with the sun sensor, which is mainly used for the attitude measurement, attitude determination and attitude control of the spacecraft. In addition, it is also used for directional control of payloads such as solar telescopes and solar panels, sun protection control of star sensors and infrared horizons, generation of switch and time scale signals, determination of phase references of spinning satellites, determination of satellite self- spin speed etc. [0003] In recent years, with the increasing requirements of satellites for attitude control accuracy and the devel...

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Problems solved by technology

[0006] But at the same time, due to the existence of the protective glass layer of the image sensor, there is always a measurement error, and as the field of view increases, the refraction of light will cause the error to increase, and the error has a nonlinear relationship with the measurement angle. There is no analytical solution, which has a negative impact on the design and application of high-precision digital sun sensors

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