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en:mag_subsys [2017/12/01 13:43]
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en:mag_subsys [2018/01/22 18:46] (current)
ashley
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 {{ ru:​device_standart.jpg?​direct&​200|}} {{ ru:​device_standart.jpg?​direct&​200|}}
-Designing ​spacecrafts ​operating ​in low orbits a magnetometer is used as one of the devices for determining ​the orientation (usually ​added to solar sensors). The magnetometer measures magnetic field around itself and gives out three components of the magnetic field induction vector. Unit of measurement is Tesla. Under ideal conditions the magnetometer on board the satellite measures the geomagnetic field of the Earth - the thing that causes ​the compass needle to rotate ​on the ground user. However, in real life, the construction of any satellite contains magnetic materials (for example, permanent magnets of electric drives), so the magnetometer measures a certain total field of the Earth and the field of the satellite itself - the so-called superposition of fields.+When designing ​spacecrafts ​that operate ​in low earth orbitsa magnetometer is often used as one of the devices for determining orientation (usually ​supplementing the solar sensors). The magnetometer measures ​the magnetic field around itself and outputs ​three components of the magnetic field induction vector ​in Tesla units. Under ideal conditionsthe magnetometer on board the satellite measures the geomagnetic field of the Earth - the very thing that causes ​compass needle to rotate ​for the ground user. However, in real life, the construction of any satellite contains magnetic materials (for example, permanent magnets of electric drives), so the magnetometer measures a certain total magnetic ​field of the Earth and the magnetic ​field of the satellite itself - the so-called superposition of fields.
  
-The magnetic field of the Earth is well researched, ​and not only at the surface of the Earth but also in near-Earth space. ​Although there are some distinctions in its behavior ​and many not fully explored ​interesting ​effects... But this is science. To determine satellite orientation according to the magnetometer readings it is enough ​to use the accurate ​mathematical model of the magnetic field, for example IGRF, which can be laid on the satellite in the form of program code.\\+The magnetic field of the Earth is well-researched, not only at the surface of the Earthbut also in near-Earth space. ​There are, however, ​some distinctions in its behavior, including ​many interesting,​ yet not fully explored effects... But this is science. To determine ​the satellite orientation according to the magnetometer readingsit is sufficient ​to use the exact mathematical model of the magnetic field, for exampleIGRF, which can be placed ​on the satellite in the form of program code.\\
 {{ ::​earth_mag_field.jpg?​200|}} {{ ::​earth_mag_field.jpg?​200|}}
-Comparison of magnetometer readings with the calculated values ​according to the geomagnetic field model makes it possible to estimate the orientation (and in some cases the position) of the spacecraft in space. When carrying out experiments with a "​satellite"​ in the laboratory, it is proposed to use a magnetometer as an instrument both for determining the orientation and for determining the position of the satellite in "​orbit",​ i.e. for navigation. In this case special laboratory equipment creates ​the "​geomagnetic"​ field, measured by a magnetometer on board. It is controlled from the computer according to a predetermined control law.+Comparing the magnetometer readings with the calculated values ​of the geomagnetic field model makes it possible to estimate the orientation (and in some cases the position) of the spacecraft in space. When carrying out experiments with a "​satellite"​ in the laboratory, it is proposed to use a magnetometer as an instrument both for determining the orientation and for determining the position of the satellite in "​orbit",​ i.e. for navigation. In this casethe "​geomagnetic"​ field, measured by a magnetometer on-board, is created by special laboratory equipment and is controlled from the computer according to a predetermined control law.
  
-At the beginning of the experiment, users will be given a function of the magnetic field dependence on the satellite position ​on orbit above the planet. After that you should make appropriate changes ​in your program code to make it possible to determine the satellite position according to the magnetometer readings.+At the beginning of the experiment, users will be given a function of the magnetic field dependence on the satellite position ​in orbit above the planet. After that, by making the appropriate changes ​to your program codeit becomes ​possible to determine the satellite position according to the magnetometer readings.
  
-To obtain the current magnetometer readings use this function:​\\ ​+To obtain the current magnetometer readingsuse this function:​\\ ​
   int32_t magnetometer_request_raw(uint16_t num,int16_t *pRAW_dataX,​int16_t *pRAW_dataY,​int16_t *pRAW_dataZ);  ​   int32_t magnetometer_request_raw(uint16_t num,int16_t *pRAW_dataX,​int16_t *pRAW_dataY,​int16_t *pRAW_dataZ);  ​
  
- +Once again, we emphasize that inside the "​satellite,​" ​as well as on real spacecrafts,​ the magnetometer ​readings do not only depend ​on the external "​geomagnetic"​ field. Other devices (mainly [[wheel_subsys|flywheel motors]] and [[power_subsys|power supply systems]]) can interfere with measurements,​ so it is not recommended to install a magnetometer near these devices.
-Once again, we emphasize that inside the "​satellite", as well as on real spacecrafts,​ the readings of magnetometer ​depend ​not only on the external "​geomagnetic"​ field. Other devices (mainly [[wheel_subsys|flywheel motors]] and [[power_subsys|power supply systems]]) can interfere with measurements,​ so it is not recommended to install a magnetometer near these devices.+
  
en/mag_subsys.txt · Last modified: 2018/01/22 18:46 by ashley