CN101558284B - Improvements in or relating to a gyroscope - Google Patents

Abstract

A gyroscope structure (41) includes ring structure (42) supported from a central hub (43) by eight compliant support legs (44a to 44h). Primary drive transducers (45a and 45b) and secondary drive transducers (46a and 46b) are all located around and in spaced relationship with the external periphery of the ring structure (42) to create capacitive gaps and primary pick-off transducers (47a and 47b) and secondary pick-off transducers (48a and 48b) are all located around and (10) in spaced relationship with the internal periphery of the ring structure (42) to create capacitive gaps. The gyroscope structure (41) includes sixteen capacitor plates (49a to 49p) in spaced relationship to the ring structure (42) to create capacitive gaps. Two groups of capacitive plates (49a to 49d and 49i to 49l) are all located around the internal periphery of the ring structure (42) and two groups of capacitor plates (49e to 49h and 49m to 49p) are all located around the external periphery of the ring structure (42). Each capacitor plate (49a to 49p) is arranged to generate a predetermined electrostatic force, which acts upon the ring structure (42) to locally adjust the stiffness of the ring structure 42. The positioning of the transducers (45a to 48b) and capacitor plates (49a to 20 49p) reduces the effect of variation a capacitive gap with ring structure (42) due to temperature change, thereby improving the scalefactor of the gyroscope structure.

Description

Gyrostatic or about gyrostatic improvement

Technical field

The present invention relates to the vibrational structure gyroscope, this gyroscope especially but not only be suitable for use in the Coriolis-type gyroscope that utilizes micro-electronic mechanical system technique structure.

Background technology

The Coriolis-type gyroscope that utilizes microelectromechanical systems (MEMS) technology to make is widely used for various applications now.For example, this gyroscope can be used in advanced brake system, active wheel suspension or roll detection and security application in auto industry.The gyrostatic performance requirement that is used for these purposes is relatively not too high, particularly when being used to guide when comparing with military applications with the Aero-Space of controlling commonly used with gyroscope.Require in the harsh application this, the gyrostatic use of MEMS type is more rare, because with regard to skew and scale-factor stabilised property, the gyrostatic performance of MEMS type is normally incompatible.

Device described in WO2006006597 is the gyrostatic example of Coriolis-type that utilizes the MEMS technology to make, and it is configured to satisfy the performance requirement of various automotive applications.This device utilization with reference to Fig. 1 a of WO2006006597 and the described con2 θ vibration mode of 1b (here reappear and be Fig. 1 a and 1b) to operation.Be in operation; One of these vibration modes are activated into the primary carrier mode of representing like axis P; Its limit produces Coriolis force when gyroscope winds the axis rotation perpendicular to the plane that constitutes this gyrostatic planar silicon ring shown in the dotted line of Fig. 1 a, this Coriolis force is coupled to the another kind of vibration mode represented like axis S with energy; This vibration mode is a secondary response mode, and its limit is shown in the dotted line of Fig. 1 b.The amplitude of the motion that in this response modes, causes is directly proportional with the speed of rotation that is applied on acting on this gyroscope.

This gyroscope is usually with the closed-loop path mode operation.In this pattern, primary carrier mode P is driven with resonance maximum by the main driving sensor that is connected in the phase-locked loop, and the relevant automative interest increasing controlling circuit of the amplitude utilization of motion remains on steady state value basically.This automative interest increasing controlling circuit is arranged to picking up in the sensor measured motion amplitude and compare with the reference value of fixing main adopting; And dynamically regulate the driving energy level of this main driving sensor; Keeping constant signal level, and therefore keep constant motion amplitude.This is very important because the amplitude of the Coriolis force that when gyroscope rotates, causes and thereby the amplitude of scaling factor and primary carrier mode motion be directly proportional.In the operational mode of closed-loop path, Coriolis force will cause the motion with secondary response mode S, and it utilizes secondary pick-off transducers to detect, and this motion is by means of the process auxiliary drive sensor offset.Should understand, produce the direct representation that value with the driving force that keeps above-mentioned counteracting is the speed of rotation that applies owing to the Coriolis force that acts on the gyroscope by the process auxiliary drive sensor.

With regard to scaling factor, therefore this precision of gyroscope depends on the main precision of picking up sensor and process auxiliary drive sensor of adopting with stability.Main adopt pick up sensor or process auxiliary drive sensing change in gain with the direct influence scale factor.For the device described in WO2006006597, main adopt the gain of picking up sensor and process auxiliary drive sensor and mainly confirm by the planar silicon ring with the main stability of picking up the capacitance gap between each relevant sensor board of sensor or process auxiliary drive sensor of adopting.Knew already that owing to make the various material coefficient of thermal expansion of this device, these gaps changed on the temperature range of gyroscope operation.Minimum for the effect that makes temperature-induced variations on the capacitance gap, hope that under possible situation, with the made gyroscope of selecting, these materials have the lower thermal expansivity good with coupling.But the material coefficient of thermal expansion of this selection still causes the marked change of scaling factor, and this itself limits the performance level that can be realized by gyroscope again.

Utilize the device of planar silicon ring structure to require con2 θ vibration mode frequencies usually, that is, the frequency of primary carrier mode and secondary response mode is accurately mated.This provides maximum sensitivity, because the motion that is caused by Coriolis force is amplified by the quality factor of secondary response mode.The quality factor amplification that is caused by secondary response mode can reach several thousand magnitude.The MEMS manufacturing process can be produced has high-precision planar silicon ring structure.But the little defective in the geometric configuration of this structure produces little residual frequency usually and cuts apart between primary carrier mode frequency and secondary response mode frequency.For the device described in the international patent application no WO2006/006597; This frequency division can be able to compensation through utilizing additional sensor at this device run duration, and this additional sensor structurally is similar to the driving sensor that is arranged on this planar silicon ring outside and picks up sensor with adopting.Each additional sensor is arranged on the inboard of planar silicon ring.Therefore, when between the condenser armature of additional sensor and planar silicon ring, applying dc voltage compensation (offset), produce electrostatic force, and the rigidity of planar silicon ring can be regulated partly as negative spring.Therefore, utilize this additional sensor, vibration mode frequencies can be regulated with distinguishing, accurately matees to guarantee vibration mode frequencies.

The electrostatic force that is applied by additional sensor will depend on the condenser armature of additional sensor and the capacitance gap between the planar silicon ring.Because the variation of the capacitance gap that thermal expansion causes will cause the variation between the vibration mode frequencies in the whole temperature range, thereby cause the frequency division between primary carrier mode frequency and the secondary response mode frequency.This frequency division will cause the vibration of secondary response mode usually, and this vibration is the quadrature in phase form, that is, with respect to having 90 ° phase relation through applying the motion that speed of rotation causes, and also can occur when promptly this device of box lunch does not rotate.When the same-phase signal used with being used to provide speed of rotation information compared, can be very big by this kinetic signal amplitude.Under the situation that has big orthogonal signal, recover required motion and cause that signal will propose strict requirement to the phase place of detection system.

Accurately the electronic equipment of phasing can be removed orthogonal signal basically.But the physical constraints of the precision that can realize this phase bit means some orthogonal signal same-phase signal of causing of the true rotation of infringement still usually.This restriction is the main source of the gyrostatic offset error of this type.

Summary of the invention

According to an aspect of the present invention, a kind of vibrational structure gyroscope comprises: semiconductor chip; Plane of oscillation ring structure; Be arranged to support with respect to this semiconductor chip the bracing or strutting arrangement of this ring structure, this semiconductor chip, ring structure and bracing or strutting arrangement are configured to basic each other coplane; Be arranged at least one main driving sensor of causing that this ring structure vibrates with the holotype mode under the resonant frequency of holotype; Be arranged to detect at least one main adopting of the vibration of ring structure in the holotype and pick up sensor; Be arranged to detect at least one secondary pick-off transducers when the vibration of the auxiliary mode that when the axis that is basically perpendicular to ring structure applies angular velocity, causes; Be arranged to offset at least one process auxiliary drive sensor of the said auxiliary mode vibration that causes, this main driving sensor and process auxiliary drive sensor and leading adopted and picked up sensor and secondary pick-off transducers all around the periphery setting of this ring structure; And at least two oscillation frequency regulating capacitor plates that are provided with around the periphery of ring structure; Make when between at least one condenser armature and ring structure, applying a voltage; Between condenser armature and ring structure, produce electrostatic force; Regulate the frequency of said holotype and auxiliary mode to distinguish ground; To reduce poor between holotype frequency and the auxiliary mode frequency, wherein at least one condenser armature is arranged on the outside of the periphery of ring structure, and another one or a plurality of condenser armature are arranged on the inboard of the periphery of ring structure; And at least one driving sensor or adopt and pick up the inboard that sensor is arranged on the periphery of ring structure wherein, and another one or a plurality of driving sensor or another one or a plurality of adopting are picked up the outside that sensor is arranged on the periphery of ring structure.

Condenser armature can be provided with to fit in right mode; And every pair of at least one condenser armature that fits in the right condenser armature can be arranged on the outside of the periphery of ring structure, and every pair of another condenser armature that fits in the right condenser armature can be arranged on the inboard of the periphery of ring structure.Driving sensor or adopt picks up sensor and can be provided with to cooperate the right mode of sensor; And at least one sensor in the every pair of cooperation sensor can be arranged on the inboard of the periphery of ring structure, and another sensor in the every pair of cooperation sensor can be arranged on the outside of the periphery of ring structure.

Condenser armature can be provided with to fit in right mode, and at least one pair of fits in the outside that right condenser armature can be arranged on the periphery of ring structure, and one or more pairs ofly in addition fits in the inboard that right condenser armature can be arranged on the periphery of ring structure.

Condenser armature can be that one group mode is provided with four, and four condenser armatures are one group at least one group of outside that can be arranged on the periphery of ring structure, and one or more groups condenser armature can be arranged on the inboard of the periphery of ring structure in addition.

Driving sensor or adopt and pick up sensor and can be provided with to fit in right mode; And at least one pair of fits in right driving sensor or adopts and pick up the inboard that sensor can be arranged on the periphery of ring structure, and in addition one or more pairs ofly fits in right driving sensor or adopt and pick up the outside that sensor can be arranged on the periphery of ring structure.

This vibrational structure gyroscope can comprise with four be 16 condenser armatures that one group mode is provided with, wherein two group capacitor plates can be arranged on the outside of the periphery of ring structure, and other two group capacitor plates can be arranged on the inboard of the periphery of ring structure.

This driving sensor or adopt and pick up sensor and can be provided with to fit in right mode; And two pairs fit in right driving sensor or adopt and pick up the inboard that sensor can be arranged on the periphery of ring structure, and other two pairs fit in right driving sensor or adopt and pick up the outside that sensor can be arranged on the periphery of ring structure.

Four condenser armatures are that each condenser armature of one group can have corresponding condenser armature in four condenser armatures are other group of one group, and these corresponding condenser armatures can be arranged to be connected in shared voltage source.

Main driving sensor and process auxiliary drive sensor, main adopting are picked up sensor and secondary pick-off transducers and condenser armature and can be arranged to basic each other coplane, and with the basic coplane of semiconductor chip.

Bracing or strutting arrangement can comprise two or more radial compliance supporting legs, and an end of each supporting leg can support from the center hub that is positioned at the inboard semiconductor chip of ring structure, and the other end of each supporting leg can be connected in the inside circumference of ring structure.Alternatively, bracing or strutting arrangement can comprise two or more radial compliance supporting legs, and an end of each supporting leg can support from the semiconductor chip in the ring structure outside, and the other end of each supporting leg can be connected in the neighboring of ring structure.

Semiconductor chip can be sealed in the cavity that seals with formation between two supporting substrates, and the cavity of sealing can encapsulate said ring structure, bracing or strutting arrangement, main driving sensor and process auxiliary drive sensor, main adopting picked up sensor and secondary pick-off transducers and condenser armature.

Said main driving sensor and process auxiliary drive sensor, main adopting are picked up sensor and secondary pick-off transducers and condenser armature and all can be carried by one of two supporting substrates.

Said condenser armature can be that one group mode is provided with four condenser armatures; The group of four condenser armature formations can be provided with around ring structure angledly; Make that four condenser armatures constitute first group overlaps with the angle θ of ring structure basically; Second group of θ angle with 90 ° of skews that four condenser armatures constitute overlaps, and the 3rd group of constituting of four condenser armatures overlaps with 180 ° the θ angle of squinting, and the 4th group of four condenser armature formations overlaps with 270 ° the θ angle of squinting.

Description of drawings

With reference to accompanying drawing the present invention is only described by way of example below, wherein

Fig. 1 a schematically illustrates the effect according to the radial displacement of the gyroscope ring of prior art and main carrier vibration mode;

Fig. 1 b schematically illustrates the effect according to the radial displacement of the gyroscope ring of prior art and assistance response vibration mode;

Fig. 2 is according to the gyrostatic ring structure of prior art and the vertical view of condenser armature layout;

Fig. 3 is the cut-open view along the ring structure of Fig. 2 of A-A profile line, and gyrostatic support glass structure and condenser armature layout according to prior art are shown;

Fig. 4 is the vertical view according to gyroscope ring structure of the present invention and condenser armature layout;

Fig. 5 is the cut-open view along the ring structure of Fig. 4 of B-B profile line, illustrates according to gyrostatic support glass structure of the present invention and condenser armature layout.

Embodiment

With reference to figure 2, has the ring structure 2 that supports from center hub 3 by eight flexible leg 4a to 4h like the gyrostatic structure described in the WO2006/006597. Driving sensor 5a, 5b, 6a and 6b and adopt ten sensor 7a, 7b, 8a and 8b all around the excircle setting of this ring structure 2, and each and ring structure 2 are spaced apart to form capacitance gap.In closed loop operation, the main motion that two relative main driving sensor 5a and 5b are used for excitation rings structure 2.The main motion of excitation adopts ten sensor 7a by two relative masters and 7b detects.The motion of the ring structure 2 that Coriolis force causes detects with two relative secondary pick- off transducers 8a and 8b, and this Coriolis causes that motion utilizes two relative process auxiliary drive sensor 6a and 6b to offset.Gyroscope arrangement 1 comprises 16 condenser armature 9a to 9p, and condenser armature 9a to 9p all is arranged on the inside of ring structure 2, and each and ring structure 2 is spaced apart to form capacitance gap.Each condenser armature 9a to 9p is arranged to produce the predetermined electrostatic force that acts on the ring structure 2, to regulate the rigidity of this ring structure 2 partly.

In optional embodiment; Driving sensor 5a, 5b, 6a and 6b and adopt ten sensor 7a, 7b, 8a and 8b can be all around inner periphery setting around this ring structure 2, and condenser armature 9a to 9p degree can be all around the excircle setting that centers on this ring structure 2.

Therefore, when with the time with reference to the operation of figure 2 described closed-loop path operational modes, the scaling factor SF of gyroscope arrangement 1 _RATECan provide by formula 1:

${\mathrm{SF}}_{\mathrm{RATE}}=\frac{G_B{V}_0\mathrm{\ω}}{k{g}_{\mathrm{Ppo}}{g}_{\mathrm{SD}}}$ Formula 1

V wherein ₀Be that the holotype amplitude is provided with level, ω is the holotype resonant frequency, and k is the constant that comprises this resonator size and electron gain, and GB is the Brian factor, and it is the modal coupling coefficient, g _PpoBe that main adopting picked up gain, and g _SDIt is the process auxiliary drive gain.

The main ten gain g that adopt _PpoWith process auxiliary drive gain g _SDConvert with the main area of adopting ten sensor 7a and 7b and process auxiliary drive sensor 6a and 6b.Therefore, represent with A at the main area of adopting ten sensor 7a and 7b and process auxiliary drive sensor 6a and 6b, and under the situation about representing with d of ring structure 2 and the leading gap of adopting between ten sensor 7a and 7b and process auxiliary drive sensor 6a and the 6b,

$g_{\mathrm{Ppo}}\&Proportional;g_{\mathrm{SD}}\&Proportional;\frac{\mathrm{<figure-callout\; id="2"\; label="A\; d"\; filenames="H2007800463590E00021.png,H2007800463590E00022.png"\; state="\{\{state\}\}">A</figure-callout>}}{d^{}}$ Formula 2

To see that from top formula 1 and formula 2 variation of gap d will cause the change that scaling factor is bigger, scaling factor is along with d ⁴Change.

With reference to figure 3, wherein already used similar Reference numeral is used to represent and similar parts shown in Figure 2 that the ring structure 2 usefulness layer 10 of gyroscope 1 forms, and layer 10 usefulness macrocrystalline silicon are made.Ring structure 2 supports from center hub 3, and center hub 3 is fixed in the glass support layer 11 and 12 near layer 10 rigidly. Glass support layer 11 and 12 is made with silicic-boric acid pyroceram (RTM) usually.Also condenser armature 9h and the 9p with the silicon metal manufacturing directly is adhered to glass support layer 11.Supporting leg 4d and 4h are from center hub 3 support ring structures 2.

Therefore, when centering on the variation of ambient temperature of gyroscope arrangement 1, the size of gyroscope arrangement 1 will be because thermal expansion will cause variation.The displacement of ring structure 2 relative center hubs 3 will be confirmed by the expansivity of the silicon materials of making this structure.Being fixed in the displacement that layer 11 master adopt ten sensor 7a and 7b and process auxiliary drive sensor 6a and 6b rigidly will be confirmed by the expansivity that is used for making layers 11 glass material.Ring structure 2 and main driving sensor 5a, 5b and process auxiliary drive sensor 6a, 6b and main variation of adopting the gap between ten sensor 7a, 7b and secondary pick-off transducers 8a, the 8b; And the gap between ring structure 2 and the condenser armature 9a to 9p changes; Therefore mainly confirm with the different expansivity of the silicon materials of manufacturing ring structure 2 by the glass material that is used for making glass support layer 11 respectively, it typically is 10 micron dimensions.The whole service temperature range of gyroscope arrangement 1 is generally-40 to+85 ℃; On this scope; Different expansivity between glass material and the silicon materials is enough to cause ring structure 2 and main driving sensor 5a, 5b and process auxiliary drive sensor 6a and 6b and main variation of adopting the gap between ten sensor 7a, 7b and secondary pick-off transducers 8a, the 8b; Therefore and the variation in the gap between ring structure 2 and the condenser armature 9a to 9p, and cause the variation of the scaling factor of gyroscope arrangement 1.

For this gyroscope arrangement 1, the relation table of scaling factor and temperature is shown:

$\mathrm{SF}\&Proportional;\frac{1}{g_{\mathrm{Ppo}}{g}_{\mathrm{SD}}}\&Proportional;{(d+\mathrm{\&Delta;\; d})}^4$ Formula 3

Wherein Δ d changes the variation of relevant temperature from normal house temperature d with ring structure 2 and each main gap of adopting between ten sensor 7a, 7b and each process auxiliary drive sensor 6a, the 6b.Suppose that ring structure 2 and master adopt the gap between ten sensor 7a, 7b and process auxiliary drive sensor 6a, the 6b, and they are along with variation of temperature is identical, this is rational for the ring structure of radial symmetry.

Utilize the value of the expansion coefficient of silicon and glass; The inventor knows that through the finite element analogy of this gyroscope arrangement 1 ring structure 2 and each main gap of adopting between ten sensor 7a, 7b and each process auxiliary drive sensor 6a, the 6b will change about 2% in-40 to+85 ℃ temperature range of operation of gyroscope arrangement 1.Because d ⁴Relation, so scaling factor will change about 8% in this temperature range.

Also have, for the ring structure of accurately making with fabulous radially isotropic material 2, the inventor knows that two operational mode frequencies of gyroscope arrangement 1 will accurately be mated.But, cause the little residual frequency between said operational mode frequency to be cut apart usually to isotropic physical constraints of manufacturing accuracy and material.The defective of this remnants also will be aimed at along any this pattern of axis adjustment with respect to driving sensor 5a, 5b, 6a and 6b and the angle position of adopting ten sensor 7a, 7b, 8a and 8b around this ring structure 2.When ring structure 2 when its primary mode axis is driven, this defective will cause along the moving of auxiliary mode axis, along moving and motion phase quadrature along primary mode axis of auxiliary mode axis.In common closed loop operation, this motion is eliminated by means of the auxiliary driving force that is put on the suitable phasing of this ring structure 2 by process auxiliary drive sensor 6a and 6b.The amplitude of this power is called quadrature shift Ω _Quad, and confirm as:

Ω _Quad=C * Δ F * sin4 α formula 4

Wherein Δ F is that mode frequency is cut apart, and α is the mode angle with respect to the main drive shaft line, and C comprises the constant that is used for electric drive gain and condenser armature and/or size sensor each item.Because the physical constraints of manufacturing process, Δ F is usually in the scope of ± 10Hz and can be along any angle [alpha] with respect to the main drive shaft line.For accurately operation, quadrature shift Ω _QuadAmplitude must remain in certain limit, make it be no more than the driving force of process auxiliary drive sensor 6a and 6b.These requirement for restriction Δs F must be adjusted to less than ± 1Hz.This is to realize in order to the fixing dc voltage of regulating mode frequency through putting on around the condenser armature 9a to 9p of the inner periphery setting of ring structure 2.This has the effect that applies electrical spring, and this electrical spring is regulated whole resonator stiffness and therefore regulated mode frequency ω, as follows:

$\mathrm{\&omega;}=\sqrt{\frac{K+K_{\mathrm{Elec}}}{m}}$ Formula 5

Wherein K is the spring constant of ring structure 2, K _ElecBe the electrical spring constant, and m is the modal mass of ring structure 2.The electrical spring constant that is applied by single condenser armature 9a to 9p is provided by formula 6:

$K_{\mathrm{Elec}}=-\frac{{\mathrm{\&epsiv;}}_0\mathrm{A\&Delta;}{V}^2}{{\mathrm{<figure-callout\; id="3"\; label="d"\; filenames="H2007800463590E00021.png,H2007800463590E00022.png"\; state="\{\{state\}\}">d</figure-callout>}}^3}$ Formula 6

ε wherein ₀Be the specific inductive capacity of free space, A is the area of associated capacitor plate 9a to 9p, and Δ V is that the dc voltage between ring structure 2 and the associated capacitor plate 9a to 9p is poor, and d is the clearance distance between associated capacitor plate 9a to 9p and the ring structure 2.

If the control circuit of gyroscope arrangement 1 is desirable, so it accurately the district office apply to offset the homophase virial and quadrature counteracting power of the motion that Coriolis force causes.But in fact, control circuit is not desirable, and has little phase error Φ _EThis makes the component of quadrature shift be coupled to the speed passage (ratechannel) of the speed of rotation that applies as tolerance, and this brings rate shift error Ω _ERRThis error Ω _ERRAmplitude provide by formula 7:

Ω _ERR=C * Δ F * sin 4 α * sin φ _EE formula 7

With reference to figure 4, gyroscope arrangement 41 comprises the ring structure 42 that is supported from center hub 43 by eight flexible leg 44a to 44h.Driving sensor 45a, 45b, 46a and 46b and adopt ten sensor 47a, 47b, 48a and 48b all around the circumference setting of this ring structure 42, and each and ring structure 42 are spaced apart to form capacitance gap.Should be understood that; Main driving sensor 45a and 45b and process auxiliary drive sensor 46a and 46b all are provided with around the neighboring of ring structure 42 and with the neighboring spaced apart relation with ring structure 42, and main adopt ten sensor 47a and 47b and secondary pick- off transducers 48a and 48b all around the inside circumference of ring structure 42 and with the inside circumference spaced apart relation setting of ring structure 42.In closed loop operation, the main motion that two relative main driving sensor 45a and 45b are used for excitation rings structure 42.The main motion of excitation adopts ten sensor 47a by two relative masters and 47b detects.And the motion of the ring structure 42 that this Coriolis force causes detects with two relative secondary pick- off transducers 48a and 48b, and the motion that this Coriolis force causes utilizes two relative process auxiliary drive sensor 46a and 46b to offset.The value that is produced with the driving force that keeps said counteracting by process auxiliary drive sensor 46a and 46b is because the Coriolis on the gyroscope arrangement 41 causes the direct representation of the speed of rotation that power applies.

Gyroscope arrangement 41 comprises 16 condenser armature 49a to 49p, and condenser armature 49a to 49p is all around the periphery setting of ring structure 42, and each and ring structure 42 are spaced apart to form capacitance gap.Should be pointed out that condenser armature 49a to 49p is divided into four groups, per four condenser armature 49a to 49d, 49e to 49h, 49i to 49l and 49m to 49p are one group.And; 49a to 49d be one group, 49i to 49l be one group condenser armature all around the inside circumference of ring structure 42 and with the inside circumference spaced apart relation setting of ring structure 42, and 49e to 49h is one group and 49m to 49p be one group condenser armature all around the neighboring of ring structure 42 and with the neighboring spaced apart relation setting of ring structure 42.Each condenser armature 49a to 49p is arranged to produce the predetermined electrostatic force that acts on the ring structure 42, to regulate the rigidity of this ring structure 42 partly.Four condenser armature 49a to 49d are that this group of one group is provided with around ring structure 42 angledly; Angle θ with ring structure 42 overlaps basically; Four condenser armature 49e to 49h are that another group of one group is provided with around ring structure 42 angledly; Overlapping basically with the angle θ that departs from 90 °, four condenser armature 49i to 49l are that another group of one group is provided with around ring structure 42 angledly, to overlap basically with the angle θ that departs from 180 °; And four condenser armature 49m to 49p to be last group of one group be provided with around ring structure 42 angledly, to overlap basically with the angle θ that departs from 270 °.

With reference to figure 5, wherein already used similar Reference numeral is represented and the similar parts shown in Fig. 4.The ring structure 42 of gyroscope arrangement 41 is formed in the layer 50, and layer 50 usefulness macrocrystalline silicon are made.Ring structure 42 supports from center hub 43, and center hub 43 is fixed in the glass support layer 51 and 52 near layer 50 rigidly.Glass support layer 51 and 52 is made with silicic-boric acid pyroceram (RTM) usually.Also condenser armature 49h and the 49h with the silicon metal manufacturing directly is adhered to glass support layer 51.Supporting leg 44a and 44d are from center hub 43 support ring structures 42.

Fig. 5 also is illustrated in the main driving sensor 45a in ring structure 42 outsides on the side and leftward at the inboard condenser armature 49a of ring structure 42, and on right-hand side, secondary pick-off transducers 48a is in the inboard of ring structure 42, and condenser armature 49h is in the outside of ring structure 42.

Therefore, for the master of the inboard that is arranged on ring structure 42 adopts ten sensor 47a and 47b, thermal expansion will cause the variation of its clearance distance opposite with the variation of the clearance distance of outside process auxiliary drive sensor 46a that is arranged on ring structure 42 and 46b.Therefore, when temperature increases, will reduce by an amount in each main gap of adopting between ten sensor 47a and 47b and the ring structure 42 of inboard, this is measured with basic identical in the relevant recruitment in the process auxiliary drive sensor 46a in the outside and the gap between the 46b.We also remember, the main just ten gain g that adopt _PPOWith process auxiliary drive gain g _SOThe influence scale factor, and this is directly to receive ring structure 42 and each master to adopt the parameter that the capacitance gap between ten sensor 47a and 47b and each process auxiliary drive sensor 46a and the 46b directly influences respectively.Therefore, the gap changes the influence minimizing to the scaling factor of gyroscope arrangement 41.

And gyroscope arrangement 41 also reduces ring structure 42 and main driving sensor 45a, 45b and process auxiliary drive sensor 46a, 46b, master adopt the influence that the gap between ten sensor 47a, 47b and secondary pick- off transducers 48a, 48b and the condenser armature 49a to 49b changes.

For gyroscope arrangement 41, the scaling factor temperature variation can be expressed as:

$\mathrm{SF}\&Proportional;\frac{1}{g_{\mathrm{Ppo}}{g}_{\mathrm{SD}}}\&Proportional;{(d+\mathrm{\&Delta;\; d})}^2{(d-\mathrm{\&Delta;\; d})}^2$ Formula 8

As said with reference to figure 2; For having driving sensor 5a, 5b, 6a and the 6b that all is arranged in ring structure 2 outsides and adopting ten sensor 7a, 7b, 8a and 8b and therefore have the gyroscope arrangement 1 that changes like formula 3 described scaling factors; 2% clearance distance changes (promptly; Δ d/d=0.02) will cause that about 8% scaling factor changes, although the variation of clearance distance is substantially the same for each sensor 5a, 5b, 6a, 6b, 7a, 7b, 8a and 8b.But; As said with reference to figure 4; For the process auxiliary drive sensor 46a, the 46b that are constructed with the outside that is arranged on ring structure 42 be arranged on for the gyroscope arrangement 41 that the inboard master of this ring structure adopts ten sensor 47a, 47b; Importantly, therefore have like formula 8 described scaling factors variations, stand-off distance changes and will cause that 0.1% scaling factor changes between 2%.Relatively formula 3 shows with formula 8, can realize the improvement of similar two one magnitude of scaling factor.

But; Have only when at sensor 45a, 45b, 46a and the 46b in the outside and the gap changes delta d between condenser armature 49e to 49h and 49m to 49p and the ring structure 42, and at sensor 47a, 47b, 48a and the 48b of inboard and the gap changes delta d between condenser armature 49a to 49b and the 49i to 49l equates basically and this is only correct on the contrary the time.In fact, less than the improvement of expection, reason has two slightly in this improvement.First; Though the surface towards sensor 45a, 45b, 46a, 46b, 47a, 47b, 48a and the 48b of ring structure 42 and condenser armature 49a to 49p is spaced apart with very identical distance with center hub 43, sensor 45a, 45b, 46a and 46b outside being positioned at inboard sensor 47a, 47b, 48a and 48b and condenser armature 49a to 49d and 49i to 49l and being positioned at and condenser armature 49e to 49h and 49m to 49p divide the width of open loop structure 42.This means; For sensor 45a, 45b, 46a and the 46b and condenser armature 49e to 49h and the 49m to 49p that are positioned at the outside; Thermal expansion is on big slightly distance; Therefore compare with 49i to 49l with condenser armature 49a to 49d with being positioned at inboard sensor 47a, 47b, 48a and 48b, will stand big a little gap size and change.The second, the area that is adhered to the silicon layer 50 of glassy layer 51 will suppress the expansion of glassy layer 51, therefore, disturb the expansivity of two layers 501 and 51.

In Fig. 4, each is adopted on the position that inboard that ten sensor 47a, 47b, 48a and 48b be arranged on ring structure 42 occupies by condenser armature traditionally.Condenser armature 49e to 49h and 49m to 49p are arranged on the outside of ring structure 42 and are adopted traditionally on the ten sensor position occupied.

And the influence of electrostatic force of gimbal structure 42 of being used for that temperature correlation changes being produced by condenser armature 49a to 49p on the gap between condenser armature 49a to 49p and the ring structure 42 also will be enhanced with the mode that is similar to the scaling factor relation.

For gyroscope arrangement shown in Figure 21, condenser armature 9a to 9p uses with quaternate mode, and wherein the plate with angle θ, θ+90 °, θ+180 ° and θ+270 ° setting has the shared voltage that applies.Should be pointed out that angle θ measures from the primary mode axis of gyroscope arrangement 1.For single group of one group of four plate, the electrical spring constant k _ElecRepresent as follows with the relation of temperature:

$k_{\mathrm{Elec}}\&Proportional;\frac{4A}{{(d-\mathrm{\&Delta;\; d})}^3}$ Formula 9

Therefore, the gap for 2% changes, k _ElecTo change 6%, this can cause the marked change of quadrature shift in the whole service temperature range of gyroscope arrangement 1.

As for gyroscope arrangement shown in Figure 4 41, when condenser armature 49a to 49p arranges again, spring constant k _ElecBecome with the relation of temperature:

$k_{\mathrm{Elec}}\&Proportional;\frac{2A}{{(d+\mathrm{\&Delta;\; d})}^3}+\frac{2A}{{(d-\mathrm{\&Delta;\; d})}^3}$ Formula 10

It is about 0.2% that the variation in gap is reduced to, and makes quadrature shift change widely and reduce that this itself causes rate shift stability to be improved significantly again.

Therefore, in gyroscope arrangement 41, can realize the improvement ability of scaling factor and quadrature shift.

Though the device of Fig. 4 illustrates each and adopts the inboard that ten sensor 47a, 47b, 48a and 48b can be arranged on ring structure 42; And each condenser armature 49e to 49h and 49m to 49p can be arranged on the outside of ring structure 421; Wherein each driving sensor 45a, 45b, 46a and 46b are arranged on the outside of ring structure 42; And each condenser armature 49a to 49d and 49i to 49l are arranged on the inboard of ring structure 42; But; Should be appreciated that inboard that each driving sensor 45a, 45b, 46a and 46b can be arranged on ring structure 42 traditionally by the condenser armature position occupied, and condenser armature 49a to 49d and 49i to 49l can be arranged on the outside of ring structure 42 conversely traditionally by the driving sensor position occupied; Wherein each adopts the outside that ten sensor 47a, 47b, 48a and 48b are arranged on ring structure 42, and each condenser armature 49e to 49h and 49m to 49p are arranged on the inboard of ring structure 421.As alternative dispensing means; Have only some driving sensors and some to adopt and pick up the inboard powered container panel position occupied that sensor can be arranged on ring structure, and the condenser armature outside that can be arranged on ring structure is driven or is adopted ten sensor position occupied traditionally conversely.

Should be appreciated that ring structure 42 can be shape and structure such as circular, crooked, hook-type, polygonal basically.

And, should be appreciated that the silicon active zone of the layer 50 in ring structure 2 also can be used to provide circuit, this circuit can use with being positioned at the inboard sensor of ring structure, thereby uses the silicon active zone better.For example, the layer 50 in ring structure can be used to provide the JFET amplifier, is used for from adopting the signal of ten sensor 47a, 47b, 48a or one of them output of 48b.

Claims (10)

1. a vibrational structure gyroscope comprises: semiconductor chip; Plane of oscillation ring structure; Be arranged to support with respect to this semiconductor chip the bracing or strutting arrangement of this ring structure, this semiconductor chip, ring structure and bracing or strutting arrangement are configured to basic each other coplane; Be arranged at least one main driving sensor of causing that this ring structure vibrates with the holotype mode under the resonant frequency of holotype; Be arranged to detect at least one main adopting of the vibration of the ring structure under the holotype and pick up sensor; Be arranged to detect at least one secondary pick-off transducers when the auxiliary mode vibration that when the axis that is basically perpendicular to ring structure applies angular velocity, causes; Be arranged to offset at least one process auxiliary drive sensor of the said auxiliary mode vibration that causes, this main driving sensor and process auxiliary drive sensor and leading adopted and picked up sensor and secondary pick-off transducers all around the periphery setting of this ring structure; And at least two oscillation frequency regulating capacitor plates that are provided with around the periphery of ring structure; Make when between at least one condenser armature and ring structure, applying a voltage; Between condenser armature and ring structure, produce electrostatic force; Regulate the frequency of said holotype and auxiliary mode to distinguish ground; To reduce poor between holotype frequency and the auxiliary mode frequency, wherein condenser armature is that one group mode is provided with four, and four condenser armatures are one group at least one group of outside that is arranged on the periphery of ring structure; And one or more groups condenser armature is arranged on the inboard of the periphery of ring structure in addition; And driving sensor or adopt and pick up sensor and be provided with to fit in right mode wherein, and at least one pair of fits in right driving sensor or adopts and pick up the inboard that sensor is arranged on the periphery of ring structure, and one or more pairs ofly in addition fits in right driving sensor or adopt and pick up the outside that sensor is arranged on the periphery of ring structure.

2. vibrational structure gyroscope as claimed in claim 1; Comprise that with four be 16 condenser armatures that one group mode is provided with; Wherein two group capacitor plates are arranged on the outside of the periphery of ring structure, and other two group capacitor plates are arranged on the inboard of the periphery of ring structure.

3. vibrational structure gyroscope as claimed in claim 2; Driving sensor or adopt and pick up sensor and be provided with wherein to fit in right mode; And two pairs fit in right driving sensor or adopt and pick up the inboard that sensor is arranged on the periphery of ring structure, and other two pairs fit in right driving sensor or adopt and pick up the outside that sensor is arranged on the periphery of ring structure.

4. vibrational structure gyroscope as claimed in claim 2; Wherein four condenser armatures are that each condenser armature in one group has corresponding condenser armature in four condenser armatures are each other group of one group, and these corresponding condenser armatures are arranged to be connected in shared voltage source.

5. vibrational structure gyroscope as claimed in claim 1, wherein main driving sensor and process auxiliary drive sensor, main adopting are picked up sensor and secondary pick-off transducers and condenser armature and are arranged to basic each other coplane, and with the basic coplane of semiconductor chip.

6. vibrational structure gyroscope as claimed in claim 1; Wherein bracing or strutting arrangement comprises two or more radial compliance supporting legs; One end of each supporting leg supports from the center hub that is positioned at the inboard semiconductor chip of ring structure, and the other end of each supporting leg is connected in the inside circumference of ring structure.

7. vibrational structure gyroscope as claimed in claim 1; Wherein bracing or strutting arrangement comprises two or more radial compliance supporting legs; One end of each supporting leg supports from the semiconductor chip in the ring structure outside, and the other end of each supporting leg is connected in the neighboring of ring structure.

8. vibrational structure gyroscope as claimed in claim 1; Wherein semiconductor chip is sealed in the cavity that seals with formation between two supporting substrates, and the said ring structure of the cavity package of sealing, bracing or strutting arrangement, main driving sensor and process auxiliary drive sensor, main adopting are picked up sensor and secondary pick-off transducers and condenser armature.

9. vibrational structure gyroscope as claimed in claim 8, wherein said main driving sensor and process auxiliary drive sensor, main adopting are picked up sensor and secondary pick-off transducers and condenser armature and are carried by one of two supporting substrates.

10. vibrational structure gyroscope as claimed in claim 1; Wherein said condenser armature is that one group mode is provided with four condenser armatures; The group of four condenser armature formations can be provided with around ring structure angledly; Make that four condenser armatures constitute first group overlaps with the angle θ of ring structure basically; Second group of θ angle with 90 ° of skews that four condenser armatures constitute overlaps, and the 3rd group of constituting of four condenser armatures overlaps with 180 ° the θ angle of squinting, and the 4th group of four condenser armature formations overlaps with 270 ° the θ angle of squinting.

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