Sun sensor
ASun sensoris anavigational instrumentused byspacecraftto detect the position of theSun.[1][2]Sun sensors are used forattitude control,solar arraypointing,gyroupdating, andfail-saferecovery.[3][4]
In addition to spacecraft, Sun sensors find use in ground-basedweather stationsand Sun-tracking systems, and aerial vehicles includingballoonsandUAVs.[2]
Mechanism[edit]
There are various types of Sun sensors, which differ in their technology and performance characteristics. Sun presence sensors provide abinaryoutput, indicating when the Sun is within the sensor'sfield of view.AnaloganddigitalSun sensors, in contrast, indicate the angle of the Sun by continuous anddiscrete signaloutputs, respectively.[2]
In typical Sun sensors, a thin slit at the top of a rectangular chamber allows a line of light to fall on an array ofphotodetectorcells at the bottom of the chamber. A voltage is induced in these cells, which is registered electronically. By orienting two sensors perpendicular to each other, the direction of the Sun can be fully determined.[2]
Often, multiple sensors will share processing electronics.[3]
Criteria[edit]
There are a number of design and performance criteria which dictate the selection of a Sun sensor model:
- Field of view
- Angular resolution
- Accuracyandstability
- Massandvolume
- Input voltage and power
- Output characteristics (including electrical characteristics, update frequency,nonlinearity,and encoding)
- Durability (includingradiation hardeningand tolerance tovibrationandthermal cycling)
See also[edit]
References[edit]
- ^"LIASS: LInear Accurate Sun Sensor"(PDF).Airbus Defense & Space.Retrieved11 March2016.
- ^abcd"What is a Sun Sensor?".AZO Sensors. 17 June 2013.Retrieved11 March2016.
- ^ab"Digital Sun Sensors (DSS)".Adcole Corporation. Archived fromthe originalon 25 April 2016.Retrieved11 March2016.
- ^"High Accuracy Fine Sun Sensors".Adcole Corporation. Archived fromthe originalon 25 April 2016.Retrieved11 March2016.