CN104949691A - MEMS inertial component rotation-modulation testing system based on ultrasonic motor - Google Patents
MEMS inertial component rotation-modulation testing system based on ultrasonic motor Download PDFInfo
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- CN104949691A CN104949691A CN201510351515.0A CN201510351515A CN104949691A CN 104949691 A CN104949691 A CN 104949691A CN 201510351515 A CN201510351515 A CN 201510351515A CN 104949691 A CN104949691 A CN 104949691A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01C—MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY
- G01C25/00—Manufacturing, calibrating, cleaning, or repairing instruments or devices referred to in the other groups of this subclass
- G01C25/005—Manufacturing, calibrating, cleaning, or repairing instruments or devices referred to in the other groups of this subclass initial alignment, calibration or starting-up of inertial devices
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Abstract
The invention discloses an MEMS inertial component rotation-modulation testing system based on an ultrasonic motor. The MEMS inertial component rotation-modulation testing system comprises a rotary table, an inertial component, a wireless transmission unit, a data processing unit and an upper computer. The rotary table comprises a base and further comprises a coded disc, the ultrasonic motor, a table top, a driver and a bearing main shaft which are arranged inside a rotary table shell in a sleeved mode, wherein the bearing main shaft is arranged in the center of the base. The coded disc and the ultrasonic motor are coaxially arranged on the bearing main shaft, and a rotating shaft of the ultrasonic motor is fixedly connected with the table top. The upper computer sends signals to the data processing unit and outputs drive control instructions. The driver of the rotary table drives the ultrasonic motor to rotate, drives the bearing main shaft to rotate and drives the coded disc and the table top to coaxially rotate. After the inertial component obtains the angular rate information of the rotary table, the angular rate information is transmitted to the data processing unit through the wireless transmission unit to carry out strapdown resolving, and a resolving result is fed back to the upper computer. The MEMS inertial component rotation-modulation testing system has the advantages of being high in interference resisting capability, good in electromagnetic compatibility, wide in environmental application range and small and being integrated.
Description
Technical field
The present invention relates to a kind of MEMS inertia device rotation modulation test macro based on ultrasound electric machine, belong to Aero-Space location navigation and control technology field.
Background technology
In recent years, along with miniature MEMS technology and rotation modulation technology more and more ripe, rotation modulation system based on MEMS inertial navigation device develops rapidly, namely carries out rotation modulation by introducing rotating mechanism to MEMS inertance element, thus improves the performance of low precision, low cost MEMS inertial navigation device.MEMS rotation modulation technology external is at present comparatively ripe, and domestic research is started late, especially the rotation modulation turntable of system, and the performance index such as its control accuracy, volume, power consumption and external technical merit still have a certain distance.From the data found, carry out rotation modulation technology full-scale investigation the earliest and leading be the National University of Defense technology, within 2007, have developed rotation type strapdown inertial navigation system model machine, but precision is not satisfactory, the ship examination navigation error of single-shaft-rotation is approximately 17n mile/24h, laboratory static navigational precision is better than 1n mile/24h, does not provide about biaxial rotated error.Visible this respect still has a lot of need of work to complete.
At present, there are the choosing of document analysis single-shaft-rotation motion turning axle, the impact of speed of rotation on error modulation effect and the interpretational criteria of rotation approach, then on this basis, be studied the error modulation mechanism of inertial measurement cluster under different rotary motion schemes single shaft rotary strapdown inertial navitation system (SINS), last simulation analysis compares the error of different rotary motion scheme.Also document is had to propose the improvement single-shaft-rotation scheme tilting to install by IMU, analyze the program from principle and can eliminate inertial device error on three directions completely, analyze the time synchronized sex chromosome mosaicism of indexing mechanism information and optical fibre gyro information, to derive the impact of time delay on rotation type strapdown inertial navigation system attitude error, give measuring method and the compensation policy of a kind of time delay, and carry out correlation test checking.
In addition, according to the error characteristics of MEMS, have selected a kind of rotation modulation scheme of applicable MEMS strapdown inertial navitation system (SINS) and independent research principle prototype.Static and on-board measurement shows: rotation modulation can obviously suppress MEMS constant error on the impact of navigation accuracy, and in 200s, pitching and roll attitude accuracy improve 5 times, and speed and positional precision improve nearly 10 times.Other documents devise utilize the gyroscope static drift of high-precise uniaxial turntable to test tumbling, dynamic deviation test constant rate test and angular vibration test.Analyze the impact that test table speed precision and rate smoothness bring gyro test, propose the auto-compensation that rotary table base tilts, the large angular velocity demonstrating high-precise uniaxial turntable tests the benefit brought to gyroscopic drift.In addition, existing test shows, under high-intensity magnetic field, MEMS exports and will receive and have a strong impact on, and routine is maximum based on the magnetic field of its major axes orientation of motor of electromagnetic principle just, is therefore especially not suitable for the error modulation of MEMS.
Although current MEMS technology is progressively improved, it still has problems.Traditional rotation modulation turntable is due to the restriction of the equipment such as motor, driver, cause that Systematical control precision is low, volume is large, power consumption is high, remanent magnetism is strong, the easy losing lock of power down, and transmission mode underaction in system, therefore make system be unfavorable for realizing miniaturization and integrated.
Summary of the invention
Technical matters to be solved by this invention is to overcome the deficiencies in the prior art, a kind of MEMS inertia device rotation modulation test macro based on ultrasound electric machine is provided, solve that existing system control accuracy is low, volume is large, power consumption is high, remanent magnetism is strong etc., the problem such as power down losing lock, there is strong anti-interference ability, Electro Magnetic Compatibility be good, environmental adaptation scope wide, Miniaturizable and the advantage such as integrated.
The present invention specifically solves the problems of the technologies described above by the following technical solutions:
A kind of MEMS inertia device rotation modulation test macro based on ultrasound electric machine, comprise turntable, inertia device, wireless transmission unit, data processing unit, host computer, described turntable comprises pedestal and is nested with code-disc, ultrasound electric machine, table top, driver and bearing spindle in turntable shell; Wherein bearing spindle is arranged on the center of pedestal, and described code-disc and ultrasound electric machine are coaxially installed on bearing spindle, and the rotating shaft of ultrasound electric machine is fixedly connected with table top; Described driver is connected with ultrasound electric machine input end, and described inertia device is arranged at the center of table top; Described host computer is used for transmitting control signal; Described data processing unit is used for reception control signal and generates drived control instruction; Described driver is used for driving ultrasound electric machine to rotate according to steering order, and drives bearing spindle and code-disc, table top to carry out coaxial rotating; Described inertia device is for obtaining the angular rate information of turntable and being transmitted by wireless transmission unit; Described data processing unit is used for carrying out strapdown to received angular rate information and resolves, and the calculation result of acquisition is fed back to host computer.
Further, as the preferred technical scheme of the present invention: described inertia device comprises MEMS gyro and accelerometer.
Further, as the preferred technical scheme of the present invention: described angular rate information comprises angular speed, angle and rotating angular acceleration.
Further, as the preferred technical scheme of the present invention: described wireless transmission unit is wireless blue tooth module.
Further, as the preferred technical scheme of the present invention: described data processing unit is computing machine.
Further, as the preferred technical scheme of the present invention: described computing machine adopts embedded computer.
The present invention adopts technique scheme, can produce following technique effect:
(1), the MEMS inertia device rotation modulation test macro based on ultrasound electric machine provided by the invention, based on development and the application of Novel ultrasonic motor technology, development ultrasound electric machine modulation turntable, and combining wireless transmission technology, by simulation analysis and verification algorithm, realize the rotation modulation function of system.This turntable not only overcomes the difficulties such as traditional turntable volume is large, power consumption is large, precision is low, remanent magnetism is large, and have that strong anti-interference ability, Electro Magnetic Compatibility are good, environmental adaptation scope wide, Miniaturizable and the advantage such as integrated, for the MEMS rotation modulation system of later stage development high precision, low cost and MEMS inertial navigation system provide powerful technical support.
(2), based on ultrasound electric machine turntable and MEMS inertia device, the ultrasound electric machine turntable that utilizes the present invention to develop modulation MEMS gyro, compared with traditional turntable, can improve modulation accuracy and without strong magnetic interference, control accuracy is high.
(3), system is core control panel with embedded computer, completes building of rotation modulation system, realizes above-mentioned rotation modulation system, completion system test experiments by material object.The analysis of result by experiment, can verify the impact of ultrasound electric machine turntable on MEMS gyro rotation modulation accurately, for the MEMS Rotating Inertial Navigation System of later stage development high precision, low cost provides technical support.
Accompanying drawing explanation
Fig. 1 is the module diagram of the MEMS inertia device rotation modulation test macro that the present invention is based on ultrasound electric machine.
Fig. 2 is the structural scheme of mechanism of intermediate station of the present invention.
Wherein Symbol explanation: 1-pedestal, 2-code-disc, 3-ultrasound electric machine, 4-table top, 5-driver, 6-shell, 7-bearing spindle.
Embodiment
Below in conjunction with Figure of description, embodiments of the present invention are described.
As shown in Figure 1, the present invention devises a kind of MEMS inertia device rotation modulation test macro based on ultrasound electric machine, comprise turntable, inertia device, wireless transmission unit, data processing unit, host computer, the structure of wherein said turntable as shown in Figure 2, comprises pedestal 1 and is nested with code-disc 2, ultrasound electric machine 3, table top 4, driver 5 and bearing spindle 7 in turntable shell 6; Wherein bearing spindle 7 is arranged on the center of pedestal 1, and described code-disc 2 and ultrasound electric machine 3 are coaxially installed on bearing spindle 7, and the rotating shaft of ultrasound electric machine 3 is fixedly connected with table top 4; Described driver 5 is connected with ultrasound electric machine 3 input end, and described inertia device is arranged at the center of table top 4; Described host computer is used for transmitting control signal; Described data processing unit is used for reception control signal and generates drived control instruction; Described driver is used for driving ultrasound electric machine to rotate according to steering order, and drives bearing spindle and code-disc, table top to carry out coaxial rotating; Described inertia device is for obtaining the angular rate information of turntable and being transmitted by wireless transmission unit; Described data processing unit is used for carrying out strapdown to received angular rate information and resolves, and the calculation result of acquisition is fed back to host computer.
Its principle is: transmitted control signal to data processing unit by host computer, and data processing unit exports drived control instruction; The driver 5 of described turntable drives ultrasound electric machine 3 to rotate according to steering order, drives bearing spindle 7 to rotate and code-disc 2, table top 4 coaxial rotating; Described inertia device obtains the angular rate information of turntable, and transfers to data processing unit by wireless transmission unit and carry out strapdown and resolve; By data processing unit, calculation result is fed back to host computer.
Further, in system, inertia device can adopt MEMS gyro and accelerometer, in order to analyze the modulating characteristic rotated the every error of inertia components and parts more clearly, choose the MEMS gyro of the low precision of ADI as system angle rate sensitivity components and parts, gyro exports in the mode of digital signal the angular rate information that sensitivity arrives by RS232 interface in real time.And choose the rotating angular acceleration of accelerometer measures turntable.Compared with traditional turntable, system can improve modulation accuracy and without magnetic interference, control accuracy is high.
On this basis, in system, what MEMS gyro and accelerometer module directly exported the is angular speed under inertial measurement cluster coordinate system and compare force information, need the transition matrix being tied to carrier coordinate system by inertial measurement cluster coordinate that these information are transformed into carrier coordinate system, then solve the navigational parameter of carrier by data processing module.According to navigational parameter, can verification system under the basis having inertia device, system navigate precision is effectively improved.
System, when realizing data transmission, can adopt wireless blue tooth module, reduces the complicacy on system hardware, realize the transmitting under wireless mode by wireless transmission method.
Further, the data processing unit in system, its major function is the process realizing data, can adopt computing machine.And computing machine adopts embedded, can utilize FPGA control panel, realize resolving the control of rotating mechanism and the serial communication of sensor, the strapdown that navigates and showing the functions such as storage.Turning table control and strapdown resolve integrative control, normally open loop between turning table control and device precision: steering order only ensures the accuracy of turntable, native system associates device precision and turning table control, increase the evaluation module of an inertia device precision, MEMS real-time accuracy is assessed, if improve less than an order of magnitude, then revise algorithm by FPGA, allow turntable accelerate or commutation etc.
To sum up, MEMS inertia device rotation modulation test macro based on ultrasound electric machine provided by the invention, based on development and the application of Novel ultrasonic motor technology, development ultrasound electric machine modulation turntable, and combining wireless transmission technology, by simulation analysis and verification algorithm, realize the rotation modulation function of system.This turntable not only overcomes the difficulties such as traditional turntable volume is large, power consumption is large, precision is low, and have that strong anti-interference ability, Electro Magnetic Compatibility are good, environmental adaptation scope wide, Miniaturizable and the advantage such as integrated, for the MEMS rotation modulation system of later stage development high precision, low cost and MEMS inertial navigation system provide powerful technical support.
By reference to the accompanying drawings embodiments of the present invention are explained in detail above, but the present invention is not limited to above-mentioned embodiment, in the ken that those of ordinary skill in the art possess, can also makes a variety of changes under the prerequisite not departing from present inventive concept.
Claims (6)
1. based on the MEMS inertia device rotation modulation test macro of ultrasound electric machine, it is characterized in that: comprise turntable, inertia device, wireless transmission unit, data processing unit, host computer, described turntable comprises pedestal and is nested with code-disc, ultrasound electric machine, table top, driver and bearing spindle in turntable shell; Wherein bearing spindle is arranged on the center of pedestal, and described code-disc and ultrasound electric machine are coaxially installed on bearing spindle, and the rotating shaft of ultrasound electric machine is fixedly connected with table top; Described driver is connected with ultrasound electric machine input end, and described inertia device is arranged at the center of table top; Described host computer is used for transmitting control signal; Described data processing unit is used for reception control signal and generates drived control instruction; Described driver is used for driving ultrasound electric machine to rotate according to steering order, and drives bearing spindle and code-disc, table top to carry out coaxial rotating; Described inertia device is for obtaining the angular rate information of turntable and being transmitted by wireless transmission unit; Described data processing unit is used for carrying out strapdown to received angular rate information and resolves, and the calculation result of acquisition is fed back to host computer.
2., according to claim 1 based on the MEMS inertia device rotation modulation test macro of ultrasound electric machine, it is characterized in that: described inertia device comprises MEMS gyro and accelerometer.
3., according to claim 1 based on the MEMS inertia device rotation modulation test macro of ultrasound electric machine, it is characterized in that: described angular rate information comprises angular speed, angle and rotating angular acceleration.
4., according to claim 1 based on the MEMS inertia device rotation modulation test macro of ultrasound electric machine, it is characterized in that: described wireless transmission unit is wireless blue tooth module.
5., according to claim 1 based on the MEMS inertia device rotation modulation test macro of ultrasound electric machine, it is characterized in that: described data processing unit is computing machine.
6. according to claim 5 based on the MEMS inertia device rotation modulation test macro of ultrasound electric machine, it is characterized in that: described computing machine adopts embedded computer.
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN107014400A (en) * | 2017-05-22 | 2017-08-04 | 南京信息工程大学 | The self-checking device and calibration method of unmanned plane inertial navigation unit |
| CN107192853A (en) * | 2017-07-24 | 2017-09-22 | 桂林航天工业学院 | Angular-rate sensor test device and system |
| CN109142790A (en) * | 2018-08-30 | 2019-01-04 | 恒有（苏州）精工机电有限公司 | Acceleration transducer based on lonely pole ultrasound electric machine |
| CN109254536A (en) * | 2017-07-13 | 2019-01-22 | 北京信息科技大学 | A kind of high dynamic gyro error control simulator |
| CN109959393A (en) * | 2019-04-10 | 2019-07-02 | 中国航空工业集团公司北京航空精密机械研究所 | Decision maker and its method for electronic inertial navigation turntable driving state |
| CN110940352A (en) * | 2019-11-08 | 2020-03-31 | 中国计量科学研究院 | Automatic calibration system of micro-electro-mechanical system inertia measurement unit and calibration verification method thereof |
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Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107014400A (en) * | 2017-05-22 | 2017-08-04 | 南京信息工程大学 | The self-checking device and calibration method of unmanned plane inertial navigation unit |
| CN107014400B (en) * | 2017-05-22 | 2023-09-26 | 南京信息工程大学 | Automatic calibration device and calibration method for unmanned aerial vehicle inertial navigation unit |
| CN109254536A (en) * | 2017-07-13 | 2019-01-22 | 北京信息科技大学 | A kind of high dynamic gyro error control simulator |
| CN107192853A (en) * | 2017-07-24 | 2017-09-22 | 桂林航天工业学院 | Angular-rate sensor test device and system |
| CN109142790A (en) * | 2018-08-30 | 2019-01-04 | 恒有（苏州）精工机电有限公司 | Acceleration transducer based on lonely pole ultrasound electric machine |
| CN109959393A (en) * | 2019-04-10 | 2019-07-02 | 中国航空工业集团公司北京航空精密机械研究所 | Decision maker and its method for electronic inertial navigation turntable driving state |
| CN109959393B (en) * | 2019-04-10 | 2024-09-27 | 中国航空工业集团公司北京航空精密机械研究所 | Device and method for judging galloping state of electric inertial navigation turntable |
| CN110940352A (en) * | 2019-11-08 | 2020-03-31 | 中国计量科学研究院 | Automatic calibration system of micro-electro-mechanical system inertia measurement unit and calibration verification method thereof |
| CN110940352B (en) * | 2019-11-08 | 2022-03-08 | 中国计量科学研究院 | Automatic calibration system of micro-electro-mechanical system inertia measurement unit and calibration verification method thereof |
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