CN1948906A - Capacitive type complete decoupling horizontal axis miniature mechanical gyro - Google Patents

Abstract

Translated fromChinese

本发明涉及一种电容式全解耦水平轴微机械陀螺，其特征在于：它包括玻璃衬底，驱动电容、驱动反馈电容、检测电容、驱动质量块、不对称质量块和检测质量块；驱动质量块位于中央，驱动质量块的两端分别通过横向设置的驱动模态弹性梁连接固定在玻璃衬底上的锚点；驱动电容和驱动反馈电容的可动电极连接在驱动质量块上，驱动电容和驱动反馈电容的固定电极固定在玻璃衬底上；不对称质量块外侧的两端分别通过横向设置的驱动模态弹性梁连接检测质量块，不对称质量块内侧的两端分别通过竖向设置的检测模态弹性梁连接驱动质量块；检测电容的可动电极固定在检测质量块的两侧，检测电容的固定电极固定在玻璃衬底上；检测质量块的两端分别通过竖向设置的检测模态弹性梁连接固定在玻璃衬底上的锚点。本发明具备双解耦结构，能够很好的抑制寄生效应，降低漂移；且具有良好的线性度和偏轴灵敏度。

The invention relates to a capacitive fully decoupled horizontal-axis micromechanical gyroscope, which is characterized in that it includes a glass substrate, a driving capacitor, a driving feedback capacitor, a detection capacitor, a driving mass, an asymmetric mass and a detection mass; The mass block is located in the center, and the two ends of the driving mass block are respectively connected to the anchor points fixed on the glass substrate through the laterally arranged driving mode elastic beams; the movable electrodes of the driving capacitor and the driving feedback capacitor are connected to the driving mass block, and the driving The fixed electrodes of the capacitor and the driving feedback capacitor are fixed on the glass substrate; the two ends outside the asymmetric mass block are respectively connected to the detection mass block through the drive mode elastic beams arranged horizontally, and the two ends inside the asymmetric mass block are respectively connected through the vertical The set detection mode elastic beam is connected to the drive mass; the movable electrodes of the detection capacitor are fixed on both sides of the detection mass, and the fixed electrodes of the detection capacitor are fixed on the glass substrate; the two ends of the detection mass are respectively arranged vertically The detected modal elastic beams are connected by anchors fixed on the glass substrate. The invention has a double decoupling structure, which can well suppress parasitic effects and reduce drift; and has good linearity and off-axis sensitivity.

Description

A kind of capacitive type complete decoupling horizontal axis miniature mechanical gyro

Technical field

The present invention relates to a kind of micromechanical gyro, particularly about a kind of capacitive type complete decoupling horizontal axis miniature mechanical gyro that adopts the vertical comb teeth capacitance detecting.

Background technology

Micromechanical gyro is to utilize Coriolis force to come a class inertial sensor of Measuring Object rotational angular velocity.Volume is little, in light weight, low cost and other advantages because the manufacturing of employing MEMS (micro electro mechanical system) (MEMS) technology, micromechanical gyro have, and in fields such as inertial navigation, weapon guidance, automobile, consumer electronics products very application prospects is arranged.In order to obtain the complete information that object rotates, need detect three axial angular velocity signals simultaneously, this just needs the combination of multiaxis gyro or three single shaft gyros.The gyro that adopts the MEMS technology to process three single shafts simultaneously on single chip is good solution.The normal alignment of this scheme device between each realizes automatically by structural design, avoided assembly problem, and can reduce the volume and weight of total system.In addition, adopt the gyro structure of each one-way shaft in three gyros that this technology realizes independently to do optimal design, thereby can obtain higher performance.

From gyro progress situation in the world at present, the research of Z axle gyro (being used for the inertial sensor of detection of vertical in the angular velocity of device surface direction) is quite ripe, and high performance Z axle gyro appears in the newspapers repeatly, has reached realistic scale.And the research of X, Y-axis gyro (claim the transverse axis gyro, be used to detect the inertial sensor of the angular velocity that is parallel to the device surface direction) also there is a big difference.Therefore designing and make high performance horizontal axis micromechanical gyroscope is to realize three gordian techniquies that gyro is integrated.

During gyro work, the mechanical couplings that drives and detect two mode can have a strong impact on the performance of gyro, and solution is to increase structure complexity, makes drive part and test section self-movement, realizes so-called decoupling-structure.Decoupling zero is divided into one-level decoupling zero and secondary decoupling zero (full decoupling).The one-level decoupling-structure is that motion of driving (or detection) part is independently, and detects the influence that (or driving) athletic meeting partly is activated (or detection) componental movement.Full decoupling is that driving is independently complete with the detection motion, does not interact.At present, nearly all in the world high-performance Z axle gyro all possesses the full decoupling structure.As people's such as German Gomez Gyroscope Design scheme (Proc.Transducers2005), people's such as Turkey Middle East Technical University Alper design proposal (MEMS2006).The common feature of this class gyro is the bulk silicon technological that adopts high-aspect-ratio, has big mass and big sensitization capacitance; Drive with the test section and adopt separate elastic beam constraint, its motion is only related with responsive mass, is fully independently each other, has realized the full decoupling structure, has suppressed ghost effect well, has effectively improved device performance.Detect the transverse axis gyro of Z direction motion for needs, limited by the MEMS process characteristic, need complicated elastic beam to realize off-plane movement, be difficult to realize the full decoupling structure, existing scheme has only realized the one-level decoupling zero mostly, as the torsional mode gyro structure (Sensors and Actuators A 2002) of the people such as W.Geiger of Germany design, the gyro scheme (Proc.Transducers2005) of the not contour thin tooth capacitance detecting of employing that the people such as Yang Zhenchuan of China propose.The common feature of this class gyro is to drive mode to have single-degree-of-freedom, detects mode and has two degrees of freedom, detects mode the influence that drives mode has been suppressed, and ghost effect has reduced.But be connected the common influence that the pick-up circuit that detects mode is subjected to two mode, can cause ghost effects such as quadrature error equally, limited the performance of device.

Summary of the invention

The purpose of this invention is to provide a kind of highly sensitive capacitive type complete decoupling horizontal axis miniature mechanical gyro.

For achieving the above object, the present invention takes following technical scheme: a kind of capacitive type complete decoupling horizontal axis miniature mechanical gyro, it is characterized in that: it comprises glass substrate, drives electric capacity, drive feedback electric capacity, detection electric capacity, drives mass, asymmetric mass and detects mass; Described driving mass is positioned at central authorities, and the two ends of the described driving mass driving mode elastic beam by horizontally set respectively are fastened on anchor point on the described glass substrate; The movable electrode of described driving electric capacity and drive feedback electric capacity is connected on the described driving mass, and the fixed electorde of described driving electric capacity and drive feedback electric capacity is fixed on the described glass substrate; The two ends in the described asymmetric mass outside connect described detection mass by the driving mode elastic beam of horizontally set respectively, and the two ends of described asymmetric mass inboard connect described driving mass by the detection mode elastic beam of vertical setting respectively; The movable electrode of described detection electric capacity is fixed on the both sides of described detection mass, and the fixed electorde of described detection electric capacity is fixed on the described glass substrate; The two ends of the described detection mass detection mode elastic beam by vertical setting respectively are fastened on anchor point on the described glass substrate.

Described detection sensitization capacitance adopts the not contour vertical tooth capacitance structure of dredging of both-end.

Be positioned at the described detection electric capacity of the left and right sides, each side all is divided into four groups, and two groups of electric capacity in the middle of each side are merged into a middle groups electric capacity, and making each side middle groups electric capacity is upper and lower two groups of electric capacity sums; Each side middle groups electric capacity is the movable tooth position of dredging and is higher than the fixing tooth position of dredging, the upper and lower two groups of electric capacity of each side are the movable tooth position of dredging and are lower than the fixing tooth position of dredging, the upper and lower two groups of electric capacity of one side middle groups electric capacity and opposite side are formed one and are detected electric capacity, form two altogether and detect electric capacity, it is right to form differential capacitance.

Driving mass of the present invention and asymmetric mass are under the constraint of two groups of driving elastic beams, has Y direction degree of freedom, drive between mass and the asymmetric mass and link to each other by detecting elastic beam, do not have relative motion in the Y direction between them, detect the constraint that mass is subjected to detecting elastic beam, do not have Y direction degree of freedom, so the present invention when moving, driver part does not influence the detection part motion; Be axle owing to being connected with the detection mass and the asymmetric mass that detect the electric capacity movable electrode to detect elastic beam simultaneously, can do twisting motion, detecting between mass and the asymmetric mass has the elastic beam of driving to link to each other, the two does not have relative displacement when reversing, drive mass owing to be activated the constraint of elastic beam, do not influence the driver part motion when motion that can not twist, detection part motion therefore of the present invention.The motion that is to say drive part of the present invention (comprise and drive mass and the movable tooth of dredging) and test section (comprise and detect mass and the movable tooth of dredging) only is associated with asymmetric mass separately, and the motion between them is separate motion.

The present invention is owing to take above technical scheme, it has the following advantages: 1, driving mass of the present invention and detection mass are by separate elastic beam constraint, its motion only is associated with asymmetric mass, motion between them is separate motion, be that the present invention possesses bilingual coupling structure, can suppress to drive the mechanical couplings between mode and detection mode well, thereby suppress ghost effect, effectively reduce drift.2, the present invention detects and adopts the two groups of not contour broach electric capacity of both-end Differential Detection, according to the distribution scheme among the present invention, the capacitance variations that twisting motion causes is a difference mode signal, the capacitance variations that the micro-displacement of other direction causes is common-mode signal, makes gyro have good linearty and off-axis sensitivity.

Description of drawings

Fig. 1 a, Fig. 1 b are the not contour thin tooth capacitor I type principle of work synoptic diagram of both-end of the present invention

Fig. 2 a, Fig. 2 b are the not contour thin tooth capacitor I I type principle of work synoptic diagram of both-end of the present invention

Fig. 3 is a structural representation of the present invention.

Fig. 4 a drives the mode synoptic diagram for the present invention.

Fig. 4 b detects the mode synoptic diagram for the present invention.

Embodiment

Convenient for describing the present invention, at first the not contour vertical comb teeth electric capacity of two kinds of both-ends that relates among the present invention is illustrated.

Shown in Fig. 1 a, Fig. 1 b, it is the not contour broach capacitor I of both-end type fundamental diagram,fixed electorde 1,2 andmovable electrode 3 adopts the not contour structure of both-ends, i.e. the consistency of thickness ofmovable electrode 3 andfixed electorde 1,2, and its top and bottom all is higher than the top and bottom offixed electorde 1,2.When initial position (as shown in Figure 1a), the electrode overlapping area of two electric capacity is identical, and numerical value equates.Whenmovable electrode 3 is done counterclockwise low-angle and reversed (shown in Fig. 1 b),fixed electorde 1 increases with the overlapping area ofmovable electrode 3, and promptly sensitization capacitance increases;Fixed electorde 2 reduces with the overlapping area ofmovable electrode 3, and promptly sensitization capacitance reduces.Whenmovable electrode 3 was done clockwise low-angle and reversed, the situation of the variation of sensitization capacitance when reversing counterclockwise was opposite, and the difference numerical and the windup-degree of two sensitization capacitances are proportional.

Shown in Fig. 2 a, Fig. 2 b, it is the not contour broach capacitor I of both-end I type fundamental diagram,movable electrode 3 andfixed electorde 1,2 adopts the not contour structure of both-ends, i.e. the consistency of thickness ofmovable electrode 3 andfixed electorde 1,2, and its top and bottom all is lower than the top and bottom offixed electorde 1,2.The not contour thin tooth capacitor I type of its principle of work and both-end is basic identical, but the variation of sensitization capacitance is opposite with the situation of the not contour thin tooth capacitor I type of both-end, thereby realizes that difference mode signal detects.

As shown in Figure 3, the present invention is transverse axis (X-axis) micromechanical gyro, it comprises drivingelectric capacity 4, and drive feedbackelectric capacity 5 detectselectric capacity 6,7, detect mass (housing) 8,asymmetric mass 9drives mass 10, drives modeelastic beam 11,12, detect modeelastic beam 13,14,anchor point 15,16 and glass substrate.Present embodiment comprises that eight groups driveelectric capacity 4, and every group of drivingelectric capacity 4 comprises and drivingmass 10 movable electrode that is connected and the fixed electorde that links to each other with glass substrate, driveselectric capacity 4 and adopts the push-pull type type of drive.Drive feedbackelectric capacity 5 has two groups, is used to drivingelectric capacity 4 that feedback signal is provided, and can realize that closed loop drives by additional circuit.Detectelectric capacity 6,7 and be positioned atdetection mass 8 both sides, link to each other withdetection mass 8, detectingelectric capacity 6,7 is a pair of difference sensitization capacitance, and its distribution scheme will describe in detail in the back.The present invention adopts tower structure, detectsmass 8 and links to each other with two detection modeelastic beams 14, and be fixed on the glass substrate by two anchor points 16.Detectingmass 8 links to each other withasymmetric mass 9 by four driving mode elastic beams 12.Asymmetric mass 9 is a semiclosed framework, and quality mainly concentrates on the left side.Asymmetric mass 9 detects modeelastic beam 13 by two and links to each other with driving mass 10.Driving mass 10 is rectangle, driveselectric capacity 4 and is connected drivingmass 10 both sides with feedback capacity 5.Drive mass 10 and link to each other, and be fixed on the glass substrate byanchor point 15 with four driving modeelastic beams 11.

The present invention is the transverse axis gyro of full decoupling structure, and its decoupling principle is as follows:

Drive modeelastic beam 11,12 and have less rigidity, drivemass 10 andasymmetric mass 9, therefore have Y direction degree of freedom respectively by driving 11,12 constraints of mode elastic beam in the Y direction.Drive betweenmass 10 and theasymmetric mass 9 and be connected by detection modeelastic beam 13, detect the rigidity of modeelastic beam 13 on the Y direction much larger than driving modeelastic beam 11,12, therefore drivingmass 10 does not have relative motion withasymmetric mass 9 in the Y direction.Detect the constraint thatmass 8 is subjected to detecting modeelastic beam 14, detect modeelastic beam 14 and have very large rigidity equally on the Y direction, therefore detectingmass 8 does not have Y direction degree of freedom.The driving mode that is gyro of the present invention is done the simple harmonic oscillation of Y direction for drivingmass 10 withasymmetric mass 9, keeps motionless (shown in Fig. 4 a) and detectmass 8.

As a same reason, detect modeelastic beam 13,14 and have less Y-axis torsional rigidity, and the Y-axis torsional rigidity of driving modeelastic beam 11,12 is very big.Thereforeasymmetric mass 9 has Z direction degree of freedom (along detecting the axial twisting motion of mode elastic beam) respectively withdetection mass 8 under the constraint that detects modeelastic beam 13,14;Drive mass 10 owing to be activated the constraint of modeelastic beam 11, do not have Z direction degree of freedom.Be gyro of the present invention detection mode for detectmass 8 andasymmetric mass 9 along the device axis (Y direction) do twisting motion, keep motionless (shown in Fig. 4 b) and drivemass 10.

Micromechanical gyro of the present invention utilizes Coriolis force to come Measuring Object angular velocity, as shown in Figure 3, driveselectric capacity 4 during work with the electrostatic force driving element, makes drivingmass 10 andasymmetric mass 9 vibrate along the Y direction; Detect mass and do not possess Y direction rigidity, keep static.When there is directions X angular velocity (is that axle rotates with the directions X) input in system, drive the Coriolis force thatmass 10 andasymmetric mass 9 all are subjected to Z direction (vertical substrates).Wherein drivemass 10 because barycenter on torsion shaft, can not produce axial rotation, keep original motion state; Andasymmetric mass 9 is under the effect of power in section's Leo, detectmass 8 and be connected the movable electrode that detects the detectionelectric capacity 6,7 on themass 8 driving, axially do twisting motion along detecting the mode elastic beam, thereby cause that detectingelectric capacity 6,7 changes, and can obtain the angular velocity information of X-axis input by testing circuit.

Above-mentioned analysis is assumed to desirable one dimension elastic beam (in certain direction certain rigidity being arranged, other direction rigidity infinity) with elastic beam.And the rigidity of its direction of actual elastic Liangqi is not infinity, that is to say that detectingmass 8 is not desirable single degree of freedom mass, when certain direction had the acceleration input, it may have micro-displacement in this direction, and this can influence the off-axis sensitivity of gyro.The present invention adopts following scheme head it off: the left and right sides is detected electric capacity and all is divided into four groups, and is merged into a middle groups with two groups in the middle of each side, that is the electric capacity of middle groups is upper and lower two groups of electric capacity sums.With left side electric capacity is example, and middle groups electric capacity is defined as the not contour thin tooth capacitor I type of both-end mentioned above, and upper and lower two groups of electric capacity are defined as the not contour thin tooth capacitor I I type of both-end mentioned above; The distribution of right side electric capacity is identical with definition and left side.Wherein upper and lower two groups (II type) electric capacity in left side middle groups (I type) electric capacity and right side constitute detectionelectric capacity 6; Upper and lower two groups (II type) electric capacity in right side middle groups (I type) electric capacity and left side constitute detectionelectric capacity 7, and it is right that detectionelectric capacity 6 and detectionelectric capacity 7 form differential capacitance.Serves as that a counterclockwise low-angle is when reversing when detectingmass 8 to detect modeelastic beam 14 axial directions, middle groups not contour thin tooth capacitor I type electric capacity in left side increases, the upper and lower two groups of not contour thin tooth capacitor I I type electric capacity in right side increase, and promptly detectelectric capacity 6 electric capacity and increase; Middle groups not contour thin tooth capacitor I type electric capacity in right side reduces, and the upper and lower two groups of not contour thin tooth capacitor I I type electric capacity in left side reduce, and promptly detectelectric capacity 7 electric capacity and reduce.When detectingmass 8 when the Y direction has micro-displacement, left and right sides capacitance variations situation unanimity, the situation of change that then detectselectric capacity 6,7 is also consistent.At directions X micro-displacement is arranged when detectingmass 8, for example when X positive dirction (right side) move, then left side electric capacity all reduced, and right side electric capacity all increases, and variable quantity is equal, then detectselectric capacity 6,7 and remains unchanged respectively.By above-mentioned analysis as can be known, for detectingelectric capacity 6,7, detectingmass 8 is that the capacitance variations of the detectionelectric capacity 6,7 that causes of the twisting motion of axle is a difference mode signal with the Y direction, anddetection mass 8 detectselectric capacity 6,7 when X or Y direction generation micro-displacement electric capacity is common-mode signal or remains unchanged.

Claims (3)

Translated fromChinese

1、一种电容式全解耦水平轴微机械陀螺，其特征在于：它包括玻璃衬底，驱动电容、驱动反馈电容、检测电容、驱动质量块、不对称质量块和检测质量块；所述驱动质量块位于中央，所述驱动质量块的两端分别通过横向设置的驱动模态弹性梁连接固定在所述玻璃衬底上的锚点；所述驱动电容和驱动反馈电容的可动电极连接在所述驱动质量块上，所述驱动电容和驱动反馈电容的固定电极固定在所述玻璃衬底上；所述不对称质量块外侧的两端分别通过横向设置的驱动模态弹性梁连接所述检测质量块，所述不对称质量块内侧的两端分别通过竖向设置的检测模态弹性梁连接所述驱动质量块；所述检测电容的可动电极固定在所述检测质量块的两侧，所述检测电容的固定电极固定在所述玻璃衬底上；所述检测质量块的两端分别通过竖向设置的检测模态弹性梁连接固定在所述玻璃衬底上的锚点。1. A capacitive fully decoupled horizontal-axis micromechanical gyroscope, characterized in that: it includes a glass substrate, a drive capacitor, a drive feedback capacitor, a detection capacitor, a drive mass, an asymmetric mass and a detection mass; The driving mass is located in the center, and the two ends of the driving mass are respectively connected to the anchor points fixed on the glass substrate through the driving mode elastic beams arranged laterally; the driving capacitor is connected to the movable electrode of the driving feedback capacitor On the driving mass, the fixed electrodes of the driving capacitor and the driving feedback capacitor are fixed on the glass substrate; the two ends of the outer side of the asymmetrical mass are respectively connected to each other by laterally arranged driving mode elastic beams. The detection mass block, the two ends inside the asymmetric mass block are respectively connected to the driving mass block through the detection mode elastic beams arranged vertically; the movable electrodes of the detection capacitor are fixed on the two ends of the detection mass block On the side, the fixed electrode of the detection capacitor is fixed on the glass substrate; the two ends of the detection mass are respectively connected to the anchor points fixed on the glass substrate through vertically arranged detection mode elastic beams.2、如权利要求1所述的一种电容式全解耦水平轴微机械陀螺，其特征在于：所述检测敏感电容采用双端不等高垂直疏齿电容结构。2. A capacitive fully decoupled horizontal-axis micromechanical gyroscope according to claim 1, characterized in that the detection sensitive capacitor adopts a double-terminal unequal height vertical sparse-tooth capacitor structure.3、如权利要求1或2所述的一种电容式全解耦水平轴微机械陀螺，其特征在于：位于左右两侧的所述检测电容，每一侧均等分成四组，并将每一侧中间的两组电容合并成一中间组电容，使每一侧中间组电容为上、下两组电容之和；每一侧中间组电容均为可动疏齿位置高于固定疏齿位置，每一侧上、下两组电容均为可动疏齿位置低于固定疏齿位置，，一侧中间组电容与另一侧上、下两组电容组成一个检测电容，共组成两个检测电容，形成差分电容对。3. A capacitive fully decoupled horizontal-axis micromechanical gyroscope according to claim 1 or 2, characterized in that: the detection capacitors located on the left and right sides are equally divided into four groups on each side, and each The two sets of capacitors in the middle of the side are combined into a middle set of capacitors, so that the middle set of capacitors on each side is the sum of the upper and lower sets of capacitors; The upper and lower sets of capacitors on one side are movable and the positions of the teeth are lower than the positions of the fixed teeth. The middle set of capacitors on one side and the upper and lower sets of capacitors on the other side form a detection capacitor, and a total of two detection capacitors are formed. form a differential capacitor pair.

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