System and method for maintaining optimal sensitivity of magnetometer
阅读说明：本技术 一种保持磁强计最优灵敏度的系统及方法 (System and method for maintaining optimal sensitivity of magnetometer ) 是由 刘吉利 孟超 李建朋 付明睿 胡隽 李恺 李建鹏 谷宝娟 刘琦 岳文杰 于 2020-07-16 设计创作，主要内容包括：本发明涉及一种保持磁强计最优灵敏度的系统及方法,可用来实时自动校准、保持磁强计的最优灵敏度,适用于星载磁强计等长时间连续测试、无法进行人工校准的应用场合。通过增加斜置S磁传感器的方式,在残差模块不同的判断阈值下,对三个正交的磁传感器进行数据处理和置位、复位操作,使得系统能够实时地保持最优的灵敏度,同时显著减少了三正交磁传感器的置位、复位操作,大幅降低了系统的功耗。本发明能够显著地保持系统测量的准确性以及最优灵敏度,同时通过减少系统的置位、复位操作次数,降低了系统的功耗,同时还提高了系统的可靠性等。(The invention relates to a system and a method for keeping the optimal sensitivity of a magnetometer, which can be used for automatically calibrating in real time and keeping the optimal sensitivity of the magnetometer and are suitable for application occasions where the satellite-borne magnetometer is continuously tested for a long time and manual calibration cannot be carried out. By adding the oblique S magnetic sensors, under different judgment thresholds of the residual error module, data processing, setting and resetting operations are performed on the three orthogonal magnetic sensors, so that the system can keep optimal sensitivity in real time, the setting and resetting operations of the three orthogonal magnetic sensors are obviously reduced, and the power consumption of the system is greatly reduced. The invention can obviously keep the accuracy and the optimal sensitivity of system measurement, and simultaneously reduces the power consumption of the system and improves the reliability of the system and the like by reducing the times of setting and resetting operations of the system.)
1. A system for maintaining optimal sensitivity of a magnetometer, comprising: the system comprises an S magnetic sensor, an X magnetic sensor, a Y magnetic sensor, a Z magnetic sensor, a setting and resetting module, a residual error estimation module, a switch 1 module, a switch 2 module and an output control module;
the X magnetic sensor, the Y magnetic sensor and the Z magnetic sensor are installed in a mutually orthogonal mode in pairs;
the S magnetic sensor is obliquely arranged, the fixed included angle between the S magnetic sensor and the X magnetic sensor is alpha, the fixed included angle between the S magnetic sensor and the Y magnetic sensor is beta, and the fixed included angle between the S magnetic sensor and the Z magnetic sensor is gamma; wherein, the alpha, the beta and the gamma are not equal in pairs;
The setting and resetting module is used for carrying out setting and resetting operations on the S magnetic sensor in a set period, and is also used for carrying out setting and resetting operations on the X magnetic sensor, the Y magnetic sensor and the Z magnetic sensor simultaneously when the switch 2 module is in an on state;
the S magnetic sensor is used for outputting a set output signal S +, and is also used for outputting a reset output signal S-, and outputting the generated output signal S + and the output signal S-to the residual error estimation module; when the switch 1 module is in an open state, the S magnetic sensor is also used for outputting an output signal S-to the output control module;
the residual error estimation module is used for receiving the output signal S + and the output signal S-, performing residual error processing on the received output signal S + and the output signal S-, and then outputting a judgment threshold value P1 to the switch 1 module and a judgment threshold value P2 to the switch 2 module; when the judgment threshold P1 is 1, the switch 1 module is turned on, when the judgment threshold P1 is not 1, the switch 1 module is in a turned-off state, when the judgment threshold P2 is 1, the switch 2 module is turned on, and when the judgment threshold P2 is not 1, the switch 2 module is in a turned-off state;
the output control module is used for receiving an output signal S output by the S magnetic sensor when the switch 1 module is in an open state, and is also used for receiving an output signal S of the X magnetic sensor xOutput signal S of the Y magnetic sensoryAnd the output signal S of the Z magnetic sensorzWhen the switch 1 module is in the on state, the output control module processes the received signal to generate the corrected Sx' Signal, Sy' Signal and Sz' the signal is used for three-axis control of the satellite.
2. A system for maintaining optimal sensitivity of a magnetometer according to claim 1 wherein: the setting and resetting module carries out setting and resetting operations on the polarized resistance band of the S magnetic sensor in real time, and a complete operation cycle is f0＝48kHz。
3. A system for maintaining optimal sensitivity of a magnetometer according to claim 2 wherein: the set and reset operations last for the following time:
4. a system for maintaining optimal sensitivity of a magnetometer according to claim 1 wherein: the residual error processing process comprises the following steps:
firstly, the residual error estimation module processes the output signal S + of the S magnetic sensor after setting into:
secondly, the residual error estimation module processes the output signal S-of the S magnetic sensor after reset into:
thirdly, the residual estimation module performs the following data processing according to the formula (2) and the formula (3):
and fourthly, judging by the residual error estimation module according to the formula (4), and giving a judgment threshold value:
Wherein Y is0Is a preset constant residual value.
5. A system for maintaining optimal sensitivity of a magnetometer according to claim 1 wherein: when the switch 1 module is in an on state, the method for the output control module to process the received signal comprises the following steps:
6. a system for maintaining optimal sensitivity of a magnetometer according to claim 1 wherein: the polarization resistance bands of the X magnetic sensor, the Y magnetic sensor, and the Z magnetic sensor are connected in series.
7. A system for maintaining optimal sensitivity of a magnetometer according to claim 1 wherein: the set operation was performed by applying a positive phase current of 4 amperes and 50 nanoseconds in width to the polarization resistance band of the S-magnetic sensor.
8. A system for maintaining optimal sensitivity of a magnetometer according to claim 1 wherein: the reset operation is realized by applying a negative phase current having an amplitude of 4 amperes and a width of 50 nanoseconds to the polarization resistance band of the S-magnetic sensor.
9. A method of maintaining optimal sensitivity of a magnetometer, comprising the steps of:
(1) the S magnetic sensor is set and reset by the set and reset module in a set period;
(2) The S magnetic sensor generates a set output signal S + and a reset output signal S-under the action of the setting and resetting module, and outputs the S + and S-signals to the residual error estimation module;
(3) the residual error estimation module carries out residual error processing on the received output signal S + and the output signal S-, calculates to obtain an output judgment threshold value P1, outputs the output judgment threshold value P1 to the switch 1 module, calculates to obtain an output judgment threshold value P2 and outputs the output judgment threshold value P2 to the switch 2 module;
(4) when the judgment threshold P1 is 1, the switch 1 module is turned on, when the judgment threshold P1 is not 1, the switch 1 module is turned off, when the judgment threshold P2 is 1, the switch 2 module is turned on, and when the judgment threshold P2 is not 1, the switch 2 module is turned off;
(5) when the switch 1 module is turned on, the output control module receives the output signal S-output by the S magnetic sensor and the output signal S-output by the X magnetic sensorxOutput signal S of the Y magnetic sensoryAnd the output signal S of the Z magnetic sensorzProcessing to generate corrected Sx' Signal, Sy' Signal and Sz' the signal is used for three-axis control of the satellite.
10. A method of maintaining optimal sensitivity of a magnetometer according to claim 9 wherein: when the switch 2 module is turned on, the set and reset module sets and resets the X magnetic sensor, the Y magnetic sensor, and the Z magnetic sensor at the same time.
Technical Field
The invention relates to a system and a method for keeping the optimal sensitivity of a magnetometer, which can be used for automatically calibrating in real time and keeping the optimal sensitivity of the magnetometer and are suitable for application occasions where the satellite-borne magnetometer is continuously tested for a long time and manual calibration cannot be carried out.
Background
A magnetometer based on the anisotropic magnetoresistance effect (AMR) has the advantages of high sensitivity, small volume, convenience in installation and the like, can be used for assisting in measuring the change of the attitude of a low-orbit microsatellite, and is generally composed of three orthogonally-arranged AMR magnetic sensors. The basic structure of the AMR magnetic sensor is a Wheatstone bridge consisting of four magnetic resistances, when an external bias magnetic field is applied to the bridge, the magnetization directions of two oppositely-arranged resistors rotate towards the current direction, and the resistance values of the two corresponding resistors are increased; and the resistance values of the other two oppositely-arranged resistors can be reduced, and the external magnetic field value can be obtained by measuring the differential pressure signals of the two output ends of the bridge.
The magnetometer based on the AMR magnetic sensor measures the change of the attitude of a satellite by measuring the change of the included angle between the microsatellite and the orbit geomagnetic field, and usually needs to continuously work in orbit for months or years. With long-time power-up work, the initial magnetic domain polarization direction in the AMR magnetic sensor can deflect, so that additional bias is brought to the measurement of a magnetic field, the accuracy of the magnetic field measurement is influenced, the magnetic domain polarization strength can decline, and the measurement sensitivity of a magnetometer is reduced. When the magnetometer is applied to low-orbit satellite attitude measurement, the magnetometer is also subjected to special environment interference such as space radiation, and the like, so that the measurement sensitivity of the magnetometer is reduced. In addition, the geomagnetic field at the low orbit becomes weaker relative to the earth's surface, and the magnetometer is also required to maintain optimal sensitivity in real time in order to ensure accurate measurement of the satellite attitude.
When the magnetometer is applied to the measurement of the earth surface geomagnetic field, the optimal sensitivity of the magnetometer can be kept by utilizing external calibration equipment and adopting a manual calibration mode. When the magnetometer is applied to geomagnetic measurement of a space orbit for a long time, the optimal sensitivity of the magnetometer cannot be ensured in a manual calibration mode.
The traditional magnetometer carries out setting and resetting operations on a magnetic sensor in real time before the acquisition of measurement data. Although this method can maintain the sensitivity of the magnetometer measurement, it requires a large pulse current for the set and reset operations, which results in large power consumption of the system.
Disclosure of Invention
The technical problem to be solved by the invention is as follows: the defects of the prior art are overcome, and a system and a method for keeping the optimal sensitivity of a magnetometer are provided: the system and the method are characterized in that a tilted magnetic sensor is added, a certain included angle is kept between the tilted magnetic sensor and other three orthogonally arranged magnetic sensors, residual error estimation is carried out on the tilted magnetic sensor under the assistance of a setting module and a resetting module, and then operation processing is carried out on the other three orthogonally arranged magnetic sensors. The invention is simple and reliable, does not need manual calibration, obviously reduces the system power consumption, and improves the accuracy and the reliability of the measurement of the magnetometer.
The purpose of the invention is realized by the following technical scheme:
a system for keeping the optimal sensitivity of a magnetometer comprises an S magnetic sensor, an X magnetic sensor, a Y magnetic sensor, a Z magnetic sensor, a setting and resetting module, a residual error estimation module, a switch 1 module, a switch 2 module and an output control module;
the X magnetic sensor, the Y magnetic sensor and the Z magnetic sensor are installed in a mutually orthogonal mode in pairs;
the S magnetic sensor is obliquely arranged, the fixed included angle between the S magnetic sensor and the X magnetic sensor is alpha, the fixed included angle between the S magnetic sensor and the Y magnetic sensor is beta, and the fixed included angle between the S magnetic sensor and the Z magnetic sensor is gamma; wherein, the alpha, the beta and the gamma are not equal in pairs;
the setting and resetting module is used for carrying out setting and resetting operations on the S magnetic sensor in a set period, and is also used for carrying out setting and resetting operations on the X magnetic sensor, the Y magnetic sensor and the Z magnetic sensor simultaneously when the switch 2 module is in an on state;
the S magnetic sensor is used for outputting a set output signal S +, and is also used for outputting a reset output signal S-, and outputting the generated output signal S + and the output signal S-to the residual error estimation module; when the switch 1 module is in an open state, the S magnetic sensor is also used for outputting an output signal S-to the output control module;
The residual error estimation module is used for receiving the output signal S + and the output signal S-, performing residual error processing on the received output signal S + and the output signal S-, and then outputting a judgment threshold value P1 to the switch 1 module and a judgment threshold value P2 to the switch 2 module; when the judgment threshold P1 is 1, the switch 1 module is turned on, when the judgment threshold P1 is not 1, the switch 1 module is in a turned-off state, when the judgment threshold P2 is 1, the switch 2 module is turned on, and when the judgment threshold P2 is not 1, the switch 2 module is in a turned-off state;
the output control module is used for receiving an output signal S output by the S magnetic sensor when the switch 1 module is in an open state, and is also used for receiving an output signal S of the X magnetic sensorxOutput signal S of the Y magnetic sensoryAnd the output signal S of the Z magnetic sensorzWhen the switch 1 module is in the on state, the output control module processes the received signal to generate the corrected Sx' Signal, Sy' Signal and Sz' signals are used for three-axis control of the satellite;
the setting and resetting module carries out setting and resetting operations on the polarized resistance band of the S magnetic sensor in real time, and a complete operation cycle is f048kHz, where the set and reset operations both last:
The residual error processing process comprises the following steps:
firstly, the residual error estimation module processes the output signal S + of the S magnetic sensor after setting into:
secondly, the residual error estimation module processes the output signal S-of the S magnetic sensor after reset into:
thirdly, the residual estimation module performs the following data processing according to the formula (2) and the formula (3):
and fourthly, judging by the residual error estimation module according to the formula (4), and giving a judgment threshold value:
that is, the residual estimation module sets the values of the judgment thresholds P1 and P2 according to the equations (2) - (5), wherein Y0Is a preset constant residual error value;
when the switch 1 module is in an on state, the method for the output control module to process the received signal comprises the following steps:
a method of maintaining optimal sensitivity of a magnetometer, comprising the steps of:
(1) the S magnetic sensor is set and reset by the set and reset module in a set period;
(2) the S magnetic sensor generates a set output signal S + and a reset output signal S-under the action of the setting and resetting module, and outputs the S + and S-signals to the residual error estimation module;
(3) the residual error estimation module carries out residual error processing on the received output signal S + and the output signal S-, calculates to obtain an output judgment threshold value P1, outputs the output judgment threshold value P1 to the switch 1 module, calculates to obtain an output judgment threshold value P2 and outputs the output judgment threshold value P2 to the switch 2 module;
(4) When the judgment threshold P1 is 1, the switch 1 module is turned on, when the judgment threshold P1 is not 1, the switch 1 module is turned off, when the judgment threshold P2 is 1, the switch 2 module is turned on, and when the judgment threshold P2 is not 1, the switch 2 module is turned off;
(5) when the switch 1 module is turned on, the output control module receives the output signal S-output by the S magnetic sensor and the output signal S-output by the X magnetic sensorxOutput signal S of the Y magnetic sensoryAnd the output signal S of the Z magnetic sensorzProcessing to generate corrected Sx' Signal, Sy' Signal and Sz' signals are used for three-axis control of the satellite;
(6) when the switch 2 module is turned on, the set and reset module sets and resets the X magnetic sensor, the Y magnetic sensor, and the Z magnetic sensor at the same time.
Compared with the prior art, the invention has the following beneficial effects:
(1) the invention adds the S magnetic sensor, carries out residual estimation in real time, and controls and operates other three magnetic sensors according to the estimated judgment threshold value.
(2) The S magnetic sensor performs setting and resetting operations in real time, and the output control module performs output operation processing on the S magnetic sensor and the X magnetic sensor, the Y magnetic sensor and the Z magnetic sensor, so that magnetic field measurement of the X magnetic sensor, the Y magnetic sensor and the Z magnetic sensor is more accurate.
(3) The invention reduces the setting and resetting operation times of the X magnetic sensor, the Y magnetic sensor and the Z magnetic sensor in the long-term use process, namely reduces the use of large current pulses and obviously reduces the power consumption of the system.
(4) Setting operation is realized by applying a normal phase large current with the amplitude of 4 amperes and the width of 50 nanoseconds to the polarization resistance band of the S magnetic sensor, and the output signal of the S magnetic sensor is recorded as S +; the reset operation is realized by applying a negative phase large current with the amplitude of 4 amperes and the width of 50 nanoseconds to the polarization resistance band of the S magnetic sensor, and the output signal of the S magnetic sensor is marked as S-; the polarization resistance bands of the X magnetic sensor, the Y magnetic sensor, and the Z magnetic sensor are connected in series; setting operation of the X magnetic sensor, the Y magnetic sensor and the Z magnetic sensor is realized by applying normal-phase large current with the amplitude of 4 amperes and the width of 50 nanoseconds; the reset operation of the X magnetic sensor, the Y magnetic sensor and the Z magnetic sensor is realized by implementing a negative phase large current with the amplitude of 4 amperes and the width of 50 nanoseconds;
(5) according to the system and the method for maintaining the optimal sensitivity of the magnetometer, provided by the invention, the data processing and the setting and resetting operations are carried out on the three orthogonal magnetic sensors under different judgment thresholds of the residual error module by adding the obliquely-arranged S magnetic sensors, so that the system can maintain the optimal sensitivity in real time, the setting and resetting operations of the three orthogonal magnetic sensors are obviously reduced, and the power consumption of the system is greatly reduced. The invention can obviously keep the accuracy and the optimal sensitivity of system measurement, and simultaneously reduces the power consumption of the system and improves the reliability of the system and the like by reducing the times of setting and resetting operations of the system.
Drawings
FIG. 1 is a schematic view of the mounting configuration of an S-magnetic sensor and a tri-orthogonal magnetic sensor of the present invention;
FIG. 2 is a block diagram of the system of the present invention;
fig. 3 is a schematic diagram of a series connection mode of polarization resistance bands of the three orthogonal magnetic sensors.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
A system for maintaining optimal sensitivity of a magnetometer comprises the following specific embodiments:
as shown in fig. 2, the magnetic sensor includes an S magnetic sensor 1, a set/reset module 6, a residual estimation module 5, a switch 1 module 7, a switch 2 module 8, and an output control module 9.
The four magnetic sensors of the inventive system are mounted in the configuration shown in fig. 1: the X magnetic sensor 2, the Y magnetic sensor 3 and the Z magnetic sensor 4 are installed in a mutually orthogonal mode in pairs; the S magnetic sensor 1 is obliquely installed, and installation included angles between the S magnetic sensor 1 and the X magnetic sensor 2, between the Y magnetic sensor 3 and between the S magnetic sensor 4 and the Z magnetic sensor are respectively alpha, beta and gamma, wherein the alpha, the beta and the gamma are not equal to each other in pairs.
The X magnetic sensor 2, the Y magnetic sensor 3 and the Z magnetic sensor 4 are mainly used for completing the deflection angle postures of the satellite along the X axis, the Y axis and the Z axis; the S magnetic sensor 1 is used to assist and control the X magnetic sensor 2, the Y magnetic sensor 3, and the Z magnetic sensor 4 by the residual estimation module 5.
A method for maintaining optimal sensitivity of a magnetometer comprises the following specific implementation modes:
the setting and resetting module 6 sets and resets the polarization resistance band of the S magnetic sensor 1 in real time. One complete operating cycle is f048kHz, where the set and reset operations each last approximately:
setting operation is realized by applying a normal phase large current with the amplitude of 4 amperes and the width of 50 nanoseconds to the polarization resistance band of the S magnetic sensor, and the output signal of the S magnetic sensor is recorded as S +; the reset operation is realized by applying a negative phase large current with the amplitude of 4 amperes and the width of 50 nanoseconds to the polarization resistance band of the S magnetic sensor, and the output signal of the S magnetic sensor is marked as S-;
the residual estimation module 5 performs residual estimation according to the output signal of the set and reset S magnetic sensor, and provides a judgment threshold, and the specific method is as follows:
the residual estimation module 5 first processes the set output signal S + of the S magnetic sensor into:
the residual estimation module 5 first processes the output signal S-of the post-reset S magnetic sensor into:
then, the residual estimation module 5 performs the following data processing according to equations (2) and (3):
finally, the residual estimation module 5 performs judgment according to equation (4), and gives a judgment threshold:
That is, the residual block 5 sets the values of the judgment thresholds P1 and P2 according to the equations (2) to (5), where Y is0Is a preset constant residual error value;
when the determination threshold P1 is 1, the switch 1 module 7 is turned on, and at this time, the output control module 9 performs output operation processing of the S magnetic sensor 1 and the X magnetic sensor 2, the Y magnetic sensor 3, and the Z magnetic sensor 4, specifically:
wherein S isx、SxAnd SzRaw outputs of the X magnetic sensor 2, the Y magnetic sensor 3, and the Z magnetic sensor 4, respectively; sx'、Sy' and Sz' is the final Z-axis, Y-axis and Z-axis measurement output of the system magnetometer.
When the determination threshold P2 is 1, the switch 2 module 8 is turned on, and the set/reset module 6 sets and resets the X magnetic sensor 2, the Y magnetic sensor 3, and the Z magnetic sensor 4. The polarization resistance bands of the X magnetic sensor 2, the Y magnetic sensor 3, and the Z magnetic sensor 4 are connected in series as shown in fig. 3. Setting operations of the X magnetic sensor 2, the Y magnetic sensor 3 and the Z magnetic sensor 4 are realized by implementing normal-phase large current with the amplitude of 4 amperes and the width of 50 nanoseconds; the reset operation of the X magnetic sensor 2, the Y magnetic sensor 3 and the Z magnetic sensor 4 is realized by implementing a negative phase large current with the amplitude of 4 amperes and the width of 50 nanoseconds;
In summary, the system and the method for maintaining the optimal sensitivity of the magnetometer provided by the invention perform data processing and setting and resetting operations on three orthogonal magnetic sensors under different judgment thresholds of the residual error module by adding the obliquely-arranged S magnetic sensors, so that the system can maintain the optimal sensitivity in real time, and meanwhile, the setting and resetting operations of the three orthogonal magnetic sensors are significantly reduced, and the power consumption of the system is greatly reduced.
Those skilled in the art will appreciate that those matters not described in detail in the present specification are well known in the art.