DE102017130384B4 - Synchronized mass gyroscope - Google Patents

Abstract

A synchronized ground MEMS device, comprising:a substrate;a first proof mass coupled to the substrate by a first tether and configured for linear motion parallel to both first and second transverse axes;a second proof mass supported by a second tether coupled to the substrate and configured for linear movement parallel to both the first and second transverse axes; anda first coupler coupling the first and second proof masses together and configured to linearly move parallel to the first axis and constrain movement of the first and second proof masses to synchronous, anti-phase linear movement such that when the first proof mass moves in a first direction parallel to the second axis, the second proof mass moves in a second direction parallel to the second axis, opposite the first direction.

Description

FIELD OF THE INVENTION

The present disclosure relates to MEMS (microelectromechanical system) devices with multiple moving masses.

BACKGROUND

Gyroscopes (sometimes referred to simply as "gyros") are rotation-sensitive devices and can therefore be used to detect rotation. MEMS gyroscopes typically contain a moving body, sometimes referred to as a "proof mass," to which an electrical signal is applied to produce motion primarily along a specific axis. This is referred to as propelling the proof mass, and the axis along which the proof mass is propelled is sometimes referred to as the "drive axis". In addition, when the gyroscope undergoes rotation, the proof mass moves along a different axis than the drive axis, sometimes referred to as the measurement axis. In some MEMS gyroscopes, rotation causes the proof mass to move linearly along the measurement axis. For others, rotation causes the proof mass to rotate. Movement of the proof mass along the measurement axis is detected, thereby providing an indication of the rotation experienced by the gyroscope.

Some MEMS gyroscopes contain multiple proof masses that are mechanically coupled together. The proof masses may be coupled together in an attempt to provide synchronous motion while inhibiting undesired motion along either the measurement or drive axis.

US 2014 / 0 260 615 A1 discloses a MEMS resonator with two vibrating masses with an anti-phase and an in-phase resonance mode, each mode having a resonance frequency, and a lever system coupled to the two vibrating masses for the anti-phase resonance to the in-phase resonance mode stiffen and/or dampen while the antiphase resonant mode remains compliant. This effectively raises the in-phase resonant frequency above the anti-phase resonant frequency and potentially creates a large frequency separation between the two resonant modes. This reduces the energy transfer between the two modes, resulting in greater robustness to external accelerations since the in-phase mode has a higher frequency. The anti-phase resonance lever system is arranged between the two resonance masses as an internal lever mechanism or around the two resonance masses as an external lever mechanism.

US 2010 / 0 313 657 A1 discloses a Z-axis vibratory gyro made with at least two decoupled vibratory tines, a drive mode mechanism coupled between the tines that structurally enforces anti-phase drive mode movement of the tines at a predetermined drive frequency to to eliminate spurious frequency modes of the anti-phase drive mode movement of the tines that are lower than the predetermined drive frequency, and to provide synchronization of the drive and scan mode movement of the tines, and a scan mode mechanism coupled between the tines arranged and configured such that It provides linearly coupled, dynamically balanced, anti-phase scan mode motion of the tines to minimize substrate energy loss and improve scan mode quality factor and rate sensitivity.

DE 10 2015 107 251 A1 discloses a gyroscope in which immunity to unwanted forces affecting signal output is provided by a checkerboard architecture of proof masses that provides a second layer of differential signals not present in known solutions. The masses are aligned parallel to each other in a two by two arrangement with two orthogonal axes of symmetry. The masses are driven to oscillate in such a way that each mass moves anti-parallel to an adjacent proof mass.

DE 10 2008 042 369 A1 discloses a coupling structure for a rotation rate sensor device, with at least one first oscillating mass and a first frame surrounding the first oscillating mass, to which the first oscillating mass is coupled; the first frame comprising four angle members, each of the angle members having at least a first leg and a second leg and coupled with the first leg and the second leg to a different adjacent one of the four angle members, respectively.

SUMMARY OF REVELATION

Micromachined inertial devices are presented that have multiple linearly moving masses coupled together by couplers that move linearly when the coupled masses exhibit antiphase motion. The couplers move in ent opposite directions from each other such that a coupler on one side of the moveable masses moves in a first linear direction and another coupler on the opposite side of the moveable masses moves in a second linear direction opposite to the first linear direction. The couplers ensure proper anti-phase movement of the masses.

In certain embodiments, a balanced multi-mass MEMS device is provided that includes a substrate, a first proof mass coupled to the substrate by a first tether and configured for linear motion, and a second proof mass coupled to the substrate by a second tether Substrate is coupled and is designed for linear movement having. The balanced multi-mass MEMS device further includes a first coupler that couples the first and second proof masses together and for linear motion when the first proof mass moves in a first direction and the second proof mass moves in a second direction opposite the first direction Moved direction is formed.

In certain embodiments, a method of operating a multi-mass balanced MEMS device is provided, comprising linearly moving a first proof mass and a second proof mass in anti-phase motion and linearly translating a first coupler coupling the first and second proof masses when the first and moving the second proof mass linearly in anti-phase motion.

In certain embodiments, a balanced multi-mass MEMS device is provided that includes a substrate, a first proof mass coupled to the substrate by a first tether and configured for linear motion, and a second proof mass coupled to the substrate by a second tether Substrate is coupled and is designed for linear movement having. The balanced multi-mass MEMS device further includes means for blocking in-phase motion of the first and second proof masses.

In certain embodiments, a synchronized mass MEMS device is provided that includes a substrate, a first proof mass coupled to the substrate by a first tether and configured for linear motion parallel to both the first and second transverse axes, and a second proof mass coupled to the substrate by a second tether and adapted for linear motion parallel to both the first and second transverse axes, a third proof mass coupled to the substrate by a third tether and adapted for linear motion parallel to both the first and second second transverse axis, and a fourth proof mass coupled to the substrate by a fourth tether and configured for linear movement parallel to both the first and second transverse axes. The device further includes a first coupler that couples the first and second proof masses together and for linear movement parallel to the first axis when the first proof mass moves in a first direction parallel to the second axis and the second proof mass moves in one of the first Direction opposite second direction moves parallel to the second axis is formed.

In certain embodiments, a method of operating a synchronized mass MEMS device having four proof masses coupled together is provided, the method comprising moving the four proof masses in linear anti-phase motion parallel to a first axis, linearly translating one of the first and the second proof mass of the four proof masses coupling the first coupler when the four proof masses move in a linear anti-phase motion parallel to the first axis, and linearly translating a second coupler coupling the third and fourth proof masses of the four proof masses when the four proof masses move in a linear Move in anti-phase motion parallel to the first axis having.

In certain embodiments, a balanced, synchronized-mass MEMS gyroscope is provided that includes a first substrate, first, second, third, and fourth proof masses suspended over and coupled to the substrate and each for translating linearly parallel to the first and second axis, and means for forcing linear anti-phase motion of the four proof masses parallel to the first axis.

character list

• 1A ist eine Blockdiagrammdarstellung eines MEMS-Bauelements mit mehreren durch sich linear bewegende Läufer miteinander gekoppelten Prüfmassen gemäß einer Ausführungsform der vorliegenden Anmeldung.
• Die 1B-1E stellen vier Zustände eines antisymmetrischen (oder Gegenphasen)Betriebs des MEMS-Bauelements von 1A dar.
• 1F ist eine Blockdiagrammdarstellung eines Gyroskops mit mehreren durch sich linear bewegende Läufer miteinander gekoppelten Prüfmassen, das mehrere sich entgegengesetzt bewegende Läufer auf einer gleichen Seite der Prüfmassen enthält, gemäß einer Ausführungsform der vorliegenden Anmeldung.
• 2A stellt ein Gyroskop mit mehreren durch sich linear bewegende Läufer der in 1A dargestellten Art miteinander gekoppelten Prüfmassen dar.
• 2B ist eine Nahansicht eines Haltebands der in dem Gyroskop von 2A enthaltenen Art zur Kopplung einer Prüfmasse mit einem beweglichen Schieber.
• 2C ist eine Nahansicht eines Ankers und Schwenkpunkts der in dem Gyroskop von 2A enthaltenen Art.
• 2D ist eine Nahansicht eines Scharniers der in dem Gyroskop von 2A enthaltenen Art.
• 2E-1 ist eine Darstellungsskizze eines schwenkbaren Gelenks der in dem Gyroskop von 2A enthaltenen Art.
• 2E-2 stellt einen ersten Verformungszustand der Struktur von 2E-1 dar, in dem die schwenkbaren Gelenksegmente in entgegengesetzte Richtungen schwenken.
• 2E-3 stellt einen zweiten Verformungszustand der Struktur von 2E-1 dar, in dem die schwenkbaren Gelenksegmente jeweils in die gleiche Richtung schwenken.
• 2F-1 ist eine Nahansicht eines Kastenfederverbinders zur Kopplung benachbarter Prüfmassen in dem Gyroskop von 2A.
• 2F-2 stellt eine gestattete Bewegung der Struktur von 2F-1 da.
• 2F-3 stellt eine verhinderte Bewegung der Struktur von 2F-1 dar.
• 2G ist eine Nahansicht eines die linearen Läufer mit einem schwenkbaren Gelenk des Gyroskops von 2A koppelnden Kopplers.
• 2H stellt ein Gyroskop mit mehreren durch sich linear bewegende Läufer der in 1F dargestellten Art miteinander gekoppelten Prüfmassen dar.
• 2I stellt einen Verformungszustand des Gyroskops von 2H dar, in dem die Prüfmassen eine Gegenphasenbewegung in die y-Richtung zeigen.
• 2J ist eine Darstellungsskizze von zwei ausgeglichenen Läufern des Gyroskops von 2I, die einen Verformungszustand zeigt.
• 2K stellt eine Alternative zu der Konfiguration von 2J dar, bei der die ausgeglichenen Läufer eines Gyroskops durch ein Gelenk, das sich im Wesentlichen senkrecht zu den Längen der Läufer erstreckt, miteinander gekoppelt sind.
• 2L stellt eine alternative Läuferkonfiguration zu der in 2H gezeigten dar, bei der mehrere linear angeordnete Läufer an ihren Innen- und Außenrändern zurückgehalten werden.
• 2M stellt eine Alternative zu der Konfiguration von 2L dar, bei der mehrere linear angeordnete Läufer direkt miteinander gekoppelt sind.
• 2N stellt einen Verformungszustand einer Struktur wie der in 2M gezeigten dar.
• 3A ist eine Blockdiagrammdarstellung eines MEMS-Bauelements mit vier durch sich linear bewegende Läufer miteinander gekoppelten Prüfmassen.
• Die 3B-3E stellen vier Zustände eines antisymmetrischen Betriebs des MEMS-Bauelements von 3A dar.
• 4A stellt einen ersten Verformungszustand eines MEMS-Gyroskops mit einer Prüfmassenanordnung von vier gekoppelten Prüfmassen und die Prüfmassen koppelnden, sich linear bewegenden Läufern dar.
• 4B stellt einen zweiten Verformungszustand des MEMS-Gyroskops von 4A dar.
• 4C stellt ein Gyroskop mit synchronisierter Masse gemäß einer nicht einschränkenden Ausführungsform der vorliegenden Anmeldung dar.
• 5 stellt ein Automobil dar, das MEMS-Bauelemente der hierin beschriebenen Arten gemäß einer nicht einschränkenden Ausführungsform der vorliegenden Anmeldung einsetzen kann.

Various aspects and embodiments of the application are described with reference to the following figures. It should be obvious that the figures are not necessarily drawn to scale. Objects appearing in multiple figures are given the same reference number in all the figures in which they appear.

• 1A Figure 12 is a block diagram representation of a MEMS device having multiple sliders interconnected by linear motion coupled proof masses according to an embodiment of the present application.
• the 1B-1E represent four states of anti-symmetric (or anti-phase) operation of the MEMS device 1A represent.
• 1F 12 is a block diagram representation of a gyroscope having multiple proof masses coupled together by linearly moving sliders, including multiple counter-moving sliders on a same side of the proof masses, according to an embodiment of the present application.
• 2A represents a gyroscope with several runners moving linearly through the in 1A illustrated type of coupled test masses.
• 2 B 12 is a close-up view of a tether used in the gyroscope of FIG 2A included method of coupling a proof mass to a moveable slider.
• 2C 12 is a close-up view of an anchor and pivot used in the gyroscope of FIG 2A contained Art.
• 2D is a close-up view of a hinge used in the gyroscope of 2A contained Art.
• 2E-1 FIG. 12 is a sketch representation of a pivotal joint used in the gyroscope of FIG 2A contained Art.
• 2E-2 represents a first state of deformation of the structure of 2E-1 represents, in which the pivotable joint segments pivot in opposite directions.
• 2E-3 represents a second deformation state of the structure of 2E-1 is, in which the pivotable joint segments each pivot in the same direction.
• 2F-1 12 is a close-up view of a box spring connector for coupling adjacent proof masses in the gyroscope of FIG 2A .
• 2F-2 represents a permitted movement of the structure of 2F-1 there.
• 2F-3 represents a prevented movement of the structure of 2F-1 represent.
• 2G is a closeup of one of the linear runners with a pivoting joint of the gyroscope 2A coupling coupler.
• 2H represents a gyroscope with several runners moving linearly through the in 1F illustrated type of coupled test masses.
• 2I represents a deformation state of the gyroscope of 2H where the proof masses show anti-phase motion in the y-direction.
• 2y is a representation sketch of two balanced gyroscope runners from 2I , showing a state of deformation.
• 2K provides an alternative to configuring 2y in which the balanced runners of a gyroscope are coupled together by a hinge extending substantially perpendicular to the lengths of the runners.
• 2L represents an alternative runner configuration to that in 2H shown, in which a plurality of linearly arranged runners are restrained at their inner and outer edges.
• 2M provides an alternative to configuring 2L in which several linearly arranged runners are coupled directly to one another.
• 2N represents a deformation state of a structure like that in 2M shown.
• 3A Figure 12 is a block diagram representation of a MEMS device having four proof masses coupled together by linearly moving sliders.
• the 3B-3E represent four states of antisymmetric operation of the MEMS device of FIG 3A represent.
• 4A Figure 12 illustrates a first strain state of a MEMS gyroscope with a proof mass assembly of four coupled proof masses and linearly moving sliders coupling the proof masses.
• 4B represents a second deformation state of the MEMS gyroscope of 4A represent.
• 4C 12 illustrates a synchronized mass gyroscope in accordance with one non-limiting embodiment of the present application.
• 5 14 illustrates an automobile that may employ MEMS devices of the types described herein, in accordance with a non-limiting embodiment of the present application.

DETAILED DESCRIPTION

Aspects of the present disclosure provide micromachined or MEMS devices having multiple proof masses coupled together by linearly moving mechanical couplers that constrain motion of the coupled proof masses to synchronous, anti-phase linear motion. The couplers move move linearly, while the proof masses exhibit linear anti-phase motion rather than pivoting or rotating. Thus, in at least some embodiments, they are referred to herein as "runners" and serve as coupling and motion-transmitting mechanisms.

In some embodiments, the MEMS device includes multiple such runners configured to move in opposite directions, thereby providing balanced operation with no net momentum from the linear motion of the runners. This can prevent undesired movement of the proof masses, thereby ensuring locking of linear and angular accelerations. The oppositely moving runners may have substantially the same masses and/or displacements.

In some embodiments, two or more proof masses of a MEMS device are arranged in a proof mass array, with sliders positioned on opposite sides of the proof mass array. The runners on opposite sides of the proof mass assembly can move linearly in opposite directions, thereby providing balanced operation. In some embodiments, multiple counter-moving runners are provided on both the same side of the proof mass assembly and on opposite sides of the proof mass assembly. Thus, in some embodiments, four or more runners may be included in a MEMS device.

Various types of MEMS devices may include runners of the types described herein. For example, MEMS gyroscopes, accelerometers, and resonators may include two or more proof masses coupled by balanced sliders of the types described herein. Other micromachined devices are also possible.

According to one aspect of the present disclosure, sliders of the types described herein are included in a MEMS gyroscope and couple two linearly moving proof masses of the MEMS gyroscope. The couplers may be configured to move linearly when the proof masses are driven along a drive axis and/or when detecting movement of the proof masses along a measurement axis. For example, the couplers may be arranged to move linearly in response to the gyroscope undergoing rotation. The sliders may resist movement when the gyroscope experiences shock or other forms of acceleration (e.g., linear or angular acceleration), and therefore gyroscopes employing such couplers may exhibit reduced acceleration sensitivity and may be referred to as acceleration-insensitive gyroscopes. In some embodiments, the sliders are arranged to provide synchronous motion in both drive and sense modes of the gyroscope or other MEMS sensor.

In some embodiments, a synchronized mass gyroscope is provided that includes four proof masses coupled by movers of the types described herein. The sliders can be configured to force linear anti-phase motion of the four coupled proof masses. This may facilitate momentum balanced operation of the synchronized mass gyroscope. In addition, the runners themselves can be momentum balanced so that their own motion does not impose a net momentum on the gyroscope.

1A Figure 1 provides a simplified form of a MEMS device in accordance with one aspect of the present application, having two linearly moving couplers (“sliders”) that resist (or block) symmetric motion (also referred to as “in-phase motion”) of the proof masses and one antisymmetric Allowing motion (also referred to as “anti-phase motion”) of proof masses, coupled proof masses. The MEMS device 100 includes a first proof mass 102a, a second proof mass 102b, a substrate 104, tethers 106a, 106b, 106c, 106d, 106e, and 106f, runners 108a and 108b, and a coupler 114.

Proof masses 102a and 102b are shown in simplified block diagram form, but may be of any suitable size and shape and may be formed of any suitable material or materials. In some embodiments, proof masses 102a and 102b are substantially rectangular, such as substantially square. They can be made of silicon or another suitable material. Proof masses 102a and 102b may be substantially identical in at least some embodiments.

The substrate 104 may be a silicon substrate (e.g., a silicon die cut from a silicon wafer) or other substrate compatible with micromachining techniques. In some embodiments, substrate 104 is formed from the same material as proof masses 102a and 102b. The proof masses 102a 10 and 102b may be formed from substrate 104 by suitable micromachining techniques, such as lithography and etching processes. In some embodiments, the formation of the proof masses 102a and 102b may include a release step in which the proof masses are released from the substrate 104 and thus separated from the substrate by a gap (or cavity).

As shown, proof masses 102a and 102b are coupled to substrate 104 by tethers 106a-106f, which may take any suitable form. A non-limiting example of a suitable tether structure is a folded tether, an example of which is provided below in connection with 2 B is described. The tethers allow proof masses 102a and 102b to move with respect to substrate 104 . The proof masses can have two degrees of freedom, meaning that they can generally move along at least two axes. This allows the proof masses to be operated in both a propulsion mode, where they are actively propelled by application of an appropriate electrical signal, and a measurement mode, where they move in response to experiencing a condition such as a Coriolis force ( in the case of a gyroscope), move, can be operated. The proof masses can also be configured to respond symmetrically in response to acceleration (in the case of an accelerometer) with independent responses in the two degrees of freedom. As a non-limiting example, given the situation where MEMS device 100 is a gyroscope, proof masses 102a and 102b may be configured and coupled to substrate 104 to move along both the x and can move along the y-axis. For example, proof masses 102a and 102b may be driven along the x-axis and move about a point 112 along the y-axis in response to rotation R of the MEMS device. The tethers 106a-106f may be of any suitable configuration to allow for such movement. Furthermore, alternative or additional tethers may be included to allow for such movement. Thus, it should be appreciated that the depiction of tethers 106a-106f is a generalization for coupling proof masses 102a and 102b to substrate 104, and that various tethering arrangements may be implemented in accordance with aspects of the present application. The one described below 2A provides an example of a suitable tethering arrangement.

Coupler 114 represents a generalization of a mechanism for coupling proof masses 102a and 102b together. Coupler 114 may be a frame spring connection, a straight beam connection, or any other suitable coupler. Alternative proof mass to proof mass coupling schemes may be implemented, including the use of additional couplers. Some examples are linked below 2A described. Coupler 114 may be used in an attempt to provide synchronous movement of proof masses 102a and 102b. An example of such a movement is given in connection with the below 1B-1E described.

Proof masses 102a and 102b are further coupled by sliders 108a and 108b, which move linearly or translationally when proof masses 102a and 102b exhibit antisymmetric (or "anti-phase") motion in the y-direction. The sliders are configured to move linearly in the directions represented by arrows 110a and 110b, in this case the positive and negative x-directions. In particular, runners 108a and 108b constrain proof masses 102a and 102b to linear anti-phase motion, moving themselves linearly when proof masses 102a and 102b move in an anti-parallel manner along the y-direction, but resisting or blocking motion. where the proof masses move in a parallel fashion along the y-direction. Thus, in at least some embodiments, the linear movement of the sliders is in a direction perpendicular to the corresponding movement of the proof masses. In the non-limiting situation where MEMS device 100 is a gyroscope, the y-direction may represent the drive or sense direction, and thus runners 108a and 108b may move the proof masses in drive or sense mode to a limit linear anti-phase motion. As described further below, additional runners may be provided to provide anti-phase linear motion in both drive and sense modes, and in at least some embodiments, the combination of runners may provide anti-phase linear motion with zero net momentum in both drive and sense modes guarantee.

Runners 108a and 108b move in opposite directions in at least some embodiments. For example, if mover 108a moves to the right along the x-axis direction, mover 108b may move to the left along the x-axis direction, and vice versa. This linear movement of the runners can be achieved through an appropriate configuration of the runner itself and/or the way in which it is coupled to the proof masses the. In some embodiments, the runners are rigid rods coupled to pivotable joints, which in turn are coupled to proof masses 102a and 102b. Pivoting movement of the pivoting joints can result in linear movement of sliders 108a and 108b. An example is linked below 2A described.

Runners 108a and 108b may be formed from any suitable material. In at least some embodiments, runners 108a and 108b are formed from the same material as proof masses 102a and 102b and are formed from substrate 104 by appropriate micromachining (e.g., lithography and etching). Runners 108a and 108b may be substantially identical, including having substantially identical masses, to provide MEMS device 100 with symmetry. The runners 108a and 108b can have lengths parallel to the x-axis and widths parallel to the y-axis, with the lengths being between 2 times and 100 times greater than the widths (or any value within that range) as a non-limiting example. are.

Although 1A Illustrating in simplified form two runners 108a and 108b, it should be appreciated that more than two runners can be, and in some embodiments are, included. In some embodiments, more than two runners are provided on a given side of proof masses 102a and 102b. The multiple runners on a given face can be configured to move in opposite directions, providing a momentum balanced configuration.

In some embodiments, multiple runners are included on multiple sides of an array of proof masses, with an equal number of the runners moving in opposite directions to provide balanced motion and thus impart no net momentum to the MEMS device. An example is linked below 1F described.

It should be appreciated that the MEMS device 100 may optionally include features in addition to those illustrated and that the nature of any such additional features may depend on the type of device (e.g., gyroscope, accelerometer, resonator). For example, one or more anchors may be included to anchor components such as proof masses 102a and 102b to substrate 104 . Electrical features having drive and sense electrodes can be included and can take any form to provide drive and sense operation. Other features may also be included.

As described above, in at least some aspects of the present application, a MEMS device (e.g., a gyroscope) may include multiple proof masses configured to exhibit synchronous, antisymmetric motion. For example, proof masses 102a and 102b of gyroscope 100 may be coupled together to provide synchronous, anti-symmetric motion. the 1B-1E represent state diagrams of such an antisymmetric motion. In these figures, the x and y axes have the same orientation as in 1A on.

For explanation, assume that the MEMS device 100 is a gyroscope and that the x-axis represents the direction of drive movement. That is, the proof masses 102a and 102b are driven along the x-axis. The y-axis represents the direction of response to a rotation and can thus be considered the measurement axis in this example.

the 1B and 1C 12 depict the movement of proof masses 102a and 102b in the drive mode and show that the movement is antisymmetric. As in 1B As shown, as proof mass 102a moves to the left (in the negative x-direction), proof mass 102b moves to the right (in the positive x-direction). As in 1C As shown, as proof mass 102a moves to the right (in the positive x-direction), proof mass 102b moves to the left (in the negative x-direction). The movement can be synchronous in that movement of one of the proof masses can cause movement of the other.

the 1D and 1E represent an antisymmetric movement of the proof masses 102a and 102b in the measurement mode. As in 1D As shown, as proof mass 102a moves up (in the positive y-direction), proof mass 102b moves down (in the negative y-direction). As in 1E As shown, as proof mass 102a moves down (in the negative y-direction), proof mass 102b moves up (in the positive y-direction). The movement can again be synchronous in that movement of one of the proof masses can cause movement of the other.

Although the 1B-1E represent linear motion in top-to-bottom and left-to-right directions, it should be apparent that any combination of such motion through a MEMS device ment can be implemented. For example, the movement of the masses may instead be along a diagonal direction (e.g., at a 45 degree angle to the x and y axes), among other things. For example, the drive axis can be at an angle of 45° to the x-axis and the measurement axis can be at an angle of 135° to the x-axis. Other orientations are also possible. Although the 1B-1C as a drive mode of operation and the 1D-1E described as pertaining to a measurement mode, it should be appreciated that the drive and measurement directions may be reversed. In general, it should be obvious that the 1B-1E represent only one example of anti-phase motion that can be implemented by a MEMS device with two moving masses, and that the directions of motion and designation of drive and measurement modes can take various forms. For example, the driving and measuring modes can be reversed compared to what is described.

The in the 1B-1E The antisymmetric (or "counterphase") motion illustrated may be desirable in at least some embodiments. The sliders 108a and 108b are configured, in at least some embodiments, to constrain the proof masses to anti-phase motion along at least one of the axes (e.g., an axis perpendicular to the direction of movement of the sliders). For example, the runners can force linear anti-phase motion of the proof masses in drive mode, measurement mode, or both. This is achieved in some embodiments by making the runners resist symmetrical movement. An example of a suitable slider configuration that resists such a symmetrical movement and therefore blocks it is given in 2A shown and described below.

As described above, in some embodiments, the MEMS device may include multiple runners on a single side of the coupled proof masses. up again 1A Referring to this, movement of runners 108a and 108b in opposite directions may provide the desired antisymmetric movement of proof masses 102a and 102b, but may undesirably allow symmetric movement of the proof masses by providing a net nonlinear momentum between the runners. Thus, aspects of the present application provide gyroscopes with balanced slider configurations where there is no net momentum or other form of imbalance resulting from the linear motion of the sliders. 1F represents an example.

The MEMS device 120 of 1F , which may be any of the types of MEMS devices previously described, includes many of the same components as MEMS device 100 of FIG 1A , but differs in that several runners are provided on the same sides of the proof masses 102a and 102b. That is, in addition to runners 108a and 108b, runners 122a and 122b are included. Like carriages 108a and 108b, carriages 122a and 122b may be configured for linear motion and may permit or constrain antisymmetric motion of proof masses 102a and 102b along the y-axis while preventing symmetric motion along the y-axis. Furthermore, the mover 122a may be configured to move in an opposite direction to that of the mover 108a, and the mover 122b may be configured to move in an opposite direction to that of the mover 108b. In this way, the linear motion of sliders 108a, 108b, 122a, and 122b imposes no net momentum on MEMS device 120. Additionally, runners 122a and 122b can have masses that are substantially the same and substantially equal to that of runners 108a and 108b, thereby providing a balanced configuration that has no net linear momentum associated with the linear motion of the runners because they are the same Have masses moving in opposite directions to the same extent.

Runners 122a and 122b may be formed from the same material as runners 108a and 108b and may be formed in substantially the same manner, for example by being formed during the same lithography and etching steps as used to form runners 108a and 108b .

2A represents a gyroscope with several runners moving linearly through the in 1A proof masses coupled together in the manner illustrated. Although a gyroscope is shown and described, it should be understood that other types of MEMS devices may utilize the runners and structures illustrated herein, such as, but not limited to, resonators and accelerometers. Gyroscope 200 includes proof masses 202a and 202b coupled by linearly moving sliders 208a and 208b. Gyroscope 200 also includes sliders 204a and 204b corresponding to proof masses 202a and 202b, respectively, and a plurality of pivoting joints 206a-206h. Pivoting joints 206a, 206b, 206c, and 206d correspond to proof mass 202a, and pivoting joints 206e, 206f, 206g, and 206h correspond to proof mass 202b. The gyroscope also includes tethers 212 that couple proof masses 202a and 202b to respective sliders 204a and 204b. In this non-limiting example, eight tethers 212 are provided, coupling each of the proof masses to its respective slider. Anchors 210 support pivot joints 206a-206h and thus sliders 204a and 204b, with the pivot joints and sliders being connected by hinges 214. FIG. In this example, eight anchors 210 are associated with each of the proof masses. Electrode regions 216 may include or receive electrodes for driving proof masses 202a and 202b along the x-axis, and electrode regions 218 may include electrodes for measuring movement of proof masses 202a and 202b along the y-axis in response to rotation of the gyroscope in the plane of the contain or include page.

Sliders 204a and 204b are moveable and are also optional. As shown, each of sliders 204a and 204b is segmented in this non-limiting example. In other words, the sliders shown can be viewed as multi-piece sliders, or sliders 204a and 204b could also be viewed as four separate sliders each. For purposes of description, slider 204a is described herein as including four segments (or portions) 205a, 205b, 205c, and 205d. Slider 204b is described herein as including four segments (or parts) 205e, 205f, 205g and 205h. Multi-section slides of this type allow one section (or part) of the slide to move in drive mode and another section to move in measure mode.

As described, the sliders are optional. They may be included to suppress driving force misalignment and/or measuring force misalignment by resisting movement orthogonal to the desired movement. However, not all embodiments include such sliders. Some embodiments include proof masses, pivoting joints, and runners, but no sliders. In such embodiments, the proof mass can be coupled directly to the pivotable joint.

Pivoting joints 206a-206h are included to reduce or completely eliminate phase quadrature. Phase quadrature is the motion of the proof masses in the direction orthogonal to the drive motion, which is ideally 90° out of phase with the Coriolis reaction. Typically, phase quadrature is undesirable because the gyroscope may not be able to distinguish between electrical signals resulting from phase quadrature as opposed to those resulting from rotation, and thus the accuracy of the gyroscope in detecting Rotation can be affected by the occurrence of phase quadrature.

Each of the illustrated pivotal joints includes two segments connected by a connector 217, an example of which is given below in connection with FIGS 2E-1 , 2E-2 and 2E-3 is described. The two segments of the pivoting joint may be of substantially the same length. In this operating state, which is the same for all pivoting joints in 2A corresponds to the condition shown, the two segments of the pivoting joint together form a substantially rigid rod in an equilibrium position. When a slider moves linearly away from a given pivot, the pivot may deflect (or bow) because the connector can flex. However, the connector 217 can resist torsion and/or shear, blocking tilting of the pivot joint and preventing rotation of the slider (and associated mass). The pivoting joint reduces or completely eliminates phase quadrature motion of the gyroscope by blocking unwanted rotation or tilting of the slider (and associated mass) while allowing the desired linear motion.

The pivotable joints are connected at pivot points to the anchors 210 and are pivoted by the hinges 214 to the sliders. In this manner, the pivotable joints may pivot about the anchors 210 in response to the sliders 204a and 204b being driven, as well as in response to the sliders 204a and 204b moving as a result of experiencing a Coriolis force.

The non-limiting example of 2A Figure 12 illustrates a MEMS device that exhibits symmetry. Not all embodiments are limited in this regard.

2 B 12 illustrates a close-up view of tether 212 of gyroscope 200 of FIG 2A In this non-limiting example, tether 212 is a double-folded tether that connects to slider 204a (or 204b) at a single point and to proof mass 202a (or 202b) at two points. The shape of the tether is not limiting as various suitable tether configurations can be used to allow movement of the proof mass relative to the slider.

2C FIG. 12 is a close-up view of an anchor 210 and pivot used in the gyroscope of FIG 2A In this non-limiting example, anchor 210 supports pivotal joint 206a at pivot point 223. Slider 204a has a shape that generally conforms to the shape of anchor 210, but is not directly or rigidly connected to arbor 210 and itself thus can move with respect to the armature 210. Given the illustrated nested arrangement of armature 210 and slider 204a, it should be apparent that the slider can move significantly more in the direction represented by arrow 220 than in the direction represented by arrow 222. In some embodiments, the slider may not move in the direction of arrow 222 at all. The other anchors of gyroscope 200 may be of substantially the same design and arrangement with respect to the pivotal joints to which they are connected.

2D 12 is a close-up view of a hinge used in gyroscope 200 of FIG 2A The hinge 214 includes an L-shaped flexure 224 in the pivot joint 206a (or other pivot joint of the gyroscope) that permits pivoting and prevents translation of the pivot joint segment with respect to the pivot point 225 . However, other configurations are also possible. Pivoting hinge 206a connects slider 204a at a single corner 225 in this non-limiting example. According to one embodiment, all hinges of gyroscope 200 have substantially the same configuration.

2E-1 Figure 12 is a sketch representation of a pivotal joint middle portion including a connector 217 of the type connecting the segments of a pivotal joint, such as may be inserted through any and all of the pivotal joints 206a-206h. Connector 217 is in 2E-1 1 is shown particularly with respect to pivot joint 206a and segments 207a and 207b, but the same configuration can be applied to the other pivot joints of gyroscope 200 as well. Pivoting joint 206a includes segments 207a and 207b. The connector 217 can be a relatively narrow and short beam that couples the two segments 207a and 207b together. The connector 217 can deflect as the two segments 207a and 208b pivot in opposite directions about their respective pivot points on the anchors 210, but can resist shear or torsion. Thus, the connector 217 can prevent the two segments 207a and 207b from pivoting in the same direction. 2E-2 and 2E-3 represent a permitted and prohibited movement of the structure 2E-1 represent.

In 2E-2 segments 207a and 207b pivot in mutually opposite directions about their pivot points supported by their respective anchors 210 as shown by the circular arrows. The connector 217 flexes to allow for this pivoting. The state of deformation shown occurs when the slide segment 205a moves translationally downward in the figure. 2E-3 Figure 12 illustrates a deformation associated with pivoting segments 207a and 207b in the same direction about their respective pivots. As shown, this would correspond to the slider segment 205a exhibiting tilting motion and would exhibit shearing of the connector 217. However, the connector resists this movement and therefore the in 2E-3 illustrated tipping is prevented by the pivoting joint configuration incorporating connector 217. Thus, when the mass or slider is attached to the oppositely pivoting segments (e.g., by hinges or other types of bending), the pivoting linkage system ensures linear movement of the mass (or slider) and reduces one by causing two segments to move in the same direction pan, caused undesired rotation. As a result, with the properly designed connector 217, the pivoting joint can prevent unwanted phase quadrature motion.

2F-1 12 is a close-up view of a box spring connector 219 for coupling adjacent proof masses in the gyroscope of FIG 2A . In particular, box spring connector 219, which is a non-limiting example of connector 114 of FIG 1A , pivot joints of adjacent proof masses, in this case pivot joints 206d and 206f. The box spring connector 219 can be any suitable size and shape. It may be positioned to permit rotation of associated pivot joints 206d and 206f in opposite directions. The box spring can resist shearing motion and thus prevent pivoting joints 206d and 206f from rotating in the same direction. In this manner, the pivotal joints connected by the box spring may allow or constrain anti-phase movement of proof masses 202a and 202b if they were in-phase movement in the x-axis direction with respect to the arrangement of FIG 2F-1 lock out. Examples of movement permitted and prohibited are given in 2F-2 or. 2F-3 shown.

In 2F-2 For example, pivotable joints 206d and 206f pivot in opposite directions about pivot points supported by their respective anchors 210 . The box spring connector 219 permits such movement by stretching in the vertical direction of the figure. 2F-3 on the other hand, represents a state in which the pivotable joints 206d and 206f pivot in the same direction about the fulcrums supported by their respective anchors. To allow for this movement, the box spring connector 219 would rotate itself counterclockwise in the direction opposite to the direction in which the pivotable joints 206d and 206f pivot. The box spring 219 resists such movement, thereby providing the desired movement of 2F-2 is forced.

Box spring connector 219 is a non-limiting example of a suitable connector for coupling the adjacent pivot joints of gyroscope 200. Alternatively, a straight beam connector may be used.

2G is a close-up of one of the gyroscope 200 slider sliders from 2A coupling coupler 221. As shown, coupler 221 may be a semi-box spring connector. However, any other suitable connector that causes slider 208a to move linearly in response to pivoting of pivot joint 206e may be implemented. That is, regarding the arrangement of 2G coupler 221 causes runner 208a to move to the right (arrow 226a) when the right side of the pivot joint moves down (arrow 228a), and causes runner to move to the left (arrow 226b) when the right side of the pivoting joint moves up (arrow 228b).

up again 2A Referring to this, in operation, the gyroscope 200 may exhibit synchronous anti-phase motion. As slider segments 205b and 205d move rightward in the positive x-direction, the top segment of pivot joint 206b and the top segment of pivot joint 206d pivot clockwise, while the bottom segment of pivot joint 206b and the bottom segment of pivot Pivot pivot 206d counterclockwise. Slider segments 205f and 205h move left in the negative x-direction. Specifically, the upper segment of pivotal joint 206f and the upper segment of pivotal joint 206h pivot counterclockwise, while the lower segment of pivotal joint 206f and the lower segment of pivotal joint 206h pivot clockwise.

In the measurement mode, the left segment of pivot joint 206a and the left segment of pivot joint 206c pivot in response to counterclockwise rotation of gyroscope 200 as slider segments 205a and 205c move down in the negative y direction, while the right segment of pivot joint 206a and the right segment of pivot joint 206c clockwise. The slider segments 205e and 205g move upwards in the positive y-direction due to the runners 208a and 208b. The left segment of pivotal joint 206e and the left segment of pivotal joint 206g pivot clockwise, and the right segment of pivotal joint 206e and the right segment of pivotal joint 106g pivot counterclockwise. Sliders 208a and 208b constrain the proof masses and sliders to such movement. That is, the slider 208a forces the right segment of the pivot joint 206a and the left segment of the pivot joint 206e to rotate in the same direction (clockwise or counterclockwise) by moving itself linearly to the right or left. Similarly, runner 208b forces the right segment of pivot joint 206c and the left segment of pivot joint 206g to rotate in the same direction by moving itself linearly to the right or left in the opposite direction of runner 208a. However, since runners 208a and 208b may be rigid rods or other rigid couplers, they prevent the coupled segments of the pivotal joints from rotating in opposite directions. Thus, the runners 208a and 208b block or completely prevent in-phase movement of the sliders 204a and 204b in the measurement mode. Therefore, acceleration of a type that tends to produce in-phase movement of the spools 204a and 204b is not detected. Accordingly, sliders 208a and 208b provide an acceleration insensitive gyroscope.

As above in connection with 1F described, in some embodiments a MEMS device, such as a MEMS gyroscope, may have a balanced slider configuration, in which multiple sliders are included on a same side of the coupled proof masses. 2H 10 illustrates a non-limiting example of an implementation of such a gyroscope. Gyroscope 250 includes many of the same in connection with 2A components already illustrated and described, and thus they will not be described again in detail here. However, the gyroscope 250 differs from that in this respect Gyroscope 200 includes a balanced slider configuration with two linearly moving sliders on either side of the coupled proof masses. In particular, gyroscope 250 includes cursors 252a, 252b, 254a and 254b.

The slider 252a is coupled to the left-most segment of the pivot joint 206a by a coupler 256a and to the right-most segment of the pivot joint 206e by a coupler 256b. Similarly, slider 252b is coupled to the left-most segment of pivot joint 206c by coupler 256c and to the right-most segment of pivot joint 206g by coupler 256d. The couplers 256a-256d may be the same and may be the same as in 2G the type of coupler shown, or any other suitable coupler that allows linear movement of sliders 252a and 252b in opposite directions.

The slider 254a is coupled to the right-most segment of the pivot joint 206a by a coupler 258a and to the left-most segment of the pivot joint 206e by a coupler 258b. The slider 254b is coupled to the right-most segment of the pivot joint 206c by a coupler 258c and to the left-most segment of the pivot joint 206g by a coupler 258d. The couplers 258a-258d may be the same and may be the same as in 2G the type of coupler shown, or any other suitable coupler that allows linear movement of sliders 254a and 254b in opposite directions.

Because runners 252a and 254a are coupled to different segments of pivot joint 206a and 206e, and because these different segments rotate in opposite directions, runners 252a and 254a move in opposite linear directions during operation, as discussed below in connection with FIG 2l is described. Likewise, because runners 252b and 254b are coupled to different segments of pivot joint 206c and 206g, and because these different segments rotate in opposite directions, runners 252b and 254b move in opposite directions during operation. Overall, runners 252a and 252b then move in opposite directions and runners 254a and 254b move in opposite directions. Thus, essentially no net linear momentum emanates from the combination of runners 252a-252b and 254a-254b as long as their masses and velocities are equal, referred to as momentum balance. This then provides a balanced slider configuration that does not impose any unwanted in-phase (symmetrical) motion on the proof masses.

Runners 252a and 252b are substantially identical, as are runners 254a and 254b. All four runners can have substantially the same mass, thereby providing a balanced configuration. In the illustrated example, runners 252a and 252b are longer (in the x-direction) than runners 254a and 254b. Runners 254a and 254b may be wider in the y-direction than runners 252a and 252b to provide substantially equal masses, or may have any other suitable configuration. It can be seen that in this example all four runners are longer in the x-direction than in the y-direction. The lengths in the x-direction can be between 2 and 100 times the widths in the y-direction, or any value within this range. Alternative dimensions are also possible.

Furthermore is off 2H It can be seen that, in the non-limiting example, runners 252a and 254a assume an interleaved configuration. Runner 254a is near the proof masses, while runner 252a is distal to the proof masses. The same applies to the runners 254b and 252b. Other configurations are also possible.

2l represents an operating state of the gyroscope 250 from 2H 12 and shows the balanced operation of rotors 252a, 252b, 254a and 254b. In the operating state shown, which can represent a state of the measurement operating mode, the proof mass 202a and the slide segments 205a and 205c move upwards in the positive y-direction. Proof mass 202b and slider segments 205e and 205g move down in the negative y direction. The left-most segment of pivot joint 206a and the right-most segment of pivot joint 206e pivot about their respective pivots clockwise so that slider 252a moves in the positive x-direction to the right. The left-most segment of pivot joint 206c and the right-most segment of pivot joint 206g pivot clockwise about their respective pivots, causing slider 252b to move in the negative x-direction to the left, and therefore in the opposite direction of the slider 252a moves.

The right-most segment of pivot joint 206a and the left-most segment of pivot joint 206e rotate about their respective pivots counterclockwise so that slider 254a moves linearly to the left in the negative x-direction. The right-most segment of pivot joint 206c and the left-most segment of pivot joint 206g rotate clockwise so that slider 254b moves in the positive x-direction to the right and therefore opposite to slider 254a. A symmetrical movement (in-phase movement) of the test masses is thus blocked due to the runners.

Thus, based on the operating status in 2l see that a balanced runner configuration is provided in which the four runners move linearly but have zero net momentum. This then reduces the likelihood that the gyroscope 250 will be subjected to an undesired movement.

2y 12 illustrates a close-up sketch of a portion of gyroscope 250, providing another representation of the movement of the runners. In particular represents 2l represents an operating state in which the spool segment 205a moves down in the negative y-direction and the spool segment 205e moves up in the positive y-direction. It can be seen that the left-most segment of pivot joint 206a and the right-most segment of pivot joint 206e pivot counterclockwise so that slider 252a moves left in the negative x-direction. The right-most segment of pivot joint 206a and the left-most segment of pivot joint 206e pivot clockwise such that slider 254a moves linearly to the right in the positive x-direction.

In some embodiments, multiple runners may be coupled together on a same side of coupled proof masses of a gyroscope. 2K represents a non-limiting example, which is a variation of the configuration of 2y represents. In 2K For example, runners 252a and 254a are coupled together by a coupler or hinge 260. Coupler 260 may be oriented generally perpendicular to both runners 252a and 254a and may have a length selected to provide a desired degree of flexibility/rigidity. The coupler 260 in some embodiments can be relatively short compared to the lengths of the runners in the x-direction, although not all embodiments are limited in this regard.

Although the 2H-2K Illustrating examples where multiple runners are juxtaposed to one side of coupled proof masses, other configurations to provide balanced runners are possible. According to some embodiments, multiple runners are linearly arranged on one side of coupled proof masses. The multiple runners can be constrained on multiple sides. An example is given in 2L shown.

2L FIG. 12 shows a partial view of a gyroscope with multiple in-line phasors as an alternative to phasors 252a and 254a. The partial view shows a portion of the slider segments 205a and 205e previously described, but omits the remainder of the sliders and proof masses for ease of illustration. Some of the components have previously been described in connection with other embodiments and thus will not be described in detail here. As shown, the device may include a plurality of linearly arranged runners 270a, 270b and 270c arranged along a common axis (or line) PP. Additionally, pivoting joints 272a and 272b are included and are coupled to opposite sides of runners 270a-270c in the same way as pivoting joints 206a and 206e. Pivot joints 272a and 272b may be the same type of pivot joints as pivot joints 206a and 206e and may be coupled to anchors 274 in the same manner that pivot joints 206a and 206e couple to anchors 210. Anchors 274 and 210 have the same construction, including pivots, as previously described in connection with anchors 210 in some embodiments.

The slider 270a may be coupled to the pivot joint 272a by a coupler 276a on one side and to the pivot joint 206a on the other side by a coupler 276b. The slider 270b may be coupled to the pivot joint 272a on one side by a coupler 276c and to the pivot joint 206a on the other side by a coupler 276d. Furthermore, the slider 270b may be coupled to the pivot joint 272b by a coupler 276e on one side and to the pivot joint 206e by a coupler 276f on the other side. The slider 270c may be coupled to the pivot joint 272b by a coupler 276g on one side and to the pivot joint 206e by a coupler 276h on the other side. The couplers 276a-276h may be of the type previously associated with 2G illustrated and described type, or they may be any other suitable type of coupler that provides linear movement of sliders 270a-270c in response to pivoting of pivotable joint 206a, 206e, 272a and 272b.

In operation, runners 270a and 270c move in the opposite direction from that of runner 270b. The runners 270a and 270c may have a combined mass substantially equal to that of the runner 270b, thereby providing a balanced configuration in which the net linear momentum of the runners is zero and the runners therefore have the sliders and/or proof masses with none impinge on unwanted movement. Therefore, in some embodiments, runners 270a and 270c are shorter than runner 270b. In some such embodiments, runners 270a and 270c have a length that is approximately equal to half the length of runner 270b.

It should be obvious that 2L Figure 12 illustrates a partial view of a gyroscope, but the in-line runners may be mirror images of each other on opposite sides of the gyroscope's sliders and proof masses. That is, the runners 252b and 254b in 2l can by a configuration like that of 2L be replaced.

The runners 270a-270c force anti-symmetrical movement of the spool segments 205a and 205e in the measurement mode of operation and prevent symmetrical movement. Thus, the gyroscopes (or other MEMS devices) that support the rotor configuration of 2L implement, have reduced acceleration sensitivity compared to gyroscopes without such runners.

2M provides an alternative to configuring 2L where the runners are directly connected to each other. Just part of the structure of 2L is shown with focus on the connection between runner 270a and 270b. As shown, these two runners can be connected together by a coupler 278 at their adjacent ends. Coupler 278 is shown as including a T-connection at the end of each of runners 270a and 270b, but alternative coupling configurations are possible. Coupler 278 is capable of bending, allowing runners 270a and 270b to move with respect to one another. Likewise, runners 270b and 270c may be directly coupled to each other in the same manner, although they are shown in FIG 2M not be shown.

2N represents a deformation state of a structure of the in 2M represented type. In this figure, more of the components of 2L reproduced, as in 2M to be shown. For example, slider segment 205e, pivotal joint 206e, runner 270c, and pivotal joint 272b are additionally illustrated. The runners 270b and 270c are connected by a coupler 280 of the same type as that associated with 2M coupler 278 described may be directly coupled to each other at adjacent ends.

In 2N it can be seen that when spool segments 205a and 205e move in linear anti-phase motion (here spool segment 205a moves linearly up in the figure while spool segment 205e moves linearly down), sliders 270a and 270c move linearly move in the same direction (to the right in this example) and in the opposite direction to runner 270b (which moves to the left in this figure). The couplers 278 and 280 can flex, allowing such movement.

It can be said that the configurations of the 2L , 2M and 2N represent a MEMS device (e.g., a gyroscope) with constrained runners. The runners 270a-270c are constrained along their length on two opposite sides (near and distal to the proof masses/sliders). This is in contrast to the configuration of 2H , in which the runners are coupled with pivoting joints on a single side along their length.

As described above, the use of two or more proof masses in a MEMS device, such as a MEMS gyroscope, can provide certain benefits. The use of four proof masses can provide reduced sensitivity to vibration correction (or g×g sensitivity) and linear acceleration (or g sensitivity) by mechanically canceling common mode signals. The use of four proof masses can also provide zero momentum imbalance, which in turn can reduce sensitivity to packet modes, which can eliminate crosstalk between multiple gyroscope cores. The geometric symmetry of using four proof masses can also allow a gyroscope to be used in mode-matched operation, thereby improving the signal-to-noise ratio (SNR) as well as allowing the gyroscope to self-calibrate on the fly (without interrupting its normal operation). . Thus, the scaling factor and the offset stability can be improved den, and recalibration using a shaking or classification table in the laboratory can be avoided. To realize such benefits, the four masses can be mechanically coupled to ensure synchronous movement. Furthermore, the use of linearly moving couplers of the types described herein may facilitate forcing anti-phase motion of the four proof masses while counteracting unwanted translational motion that is sensitive to vibration (e.g., in-phase motion).

Thus, aspects of the present application use linearly moving couplers of the types described herein to couple four proof masses together to form a synchronized mass gyroscope. The architectural challenge for MEMS gyroscopes is to preserve two degrees of freedom, since gyroscope operation uses both resonator mode (drive mode) and Coriolis-sensitive mode (measurement mode). The synchronized mass gyroscopes described herein may include linearly moving couplers that force antiphase linear motion of the four coupled proof masses in drive mode, measure mode, or both without causing interference between the two. Furthermore, the couplers are arranged to provide zero net momentum in at least some embodiments.

3A Figure 12 illustrates in simplified form a MEMS device according to an aspect of the present application having four proof masses coupled by runners of the types previously described herein configured to resist (or block) symmetrical movement of each adjacent pair of proof masses ) and allow or constrain linear anti-phase motion of the proof masses. The MEMS device 300 is an extension of the MEMS device 100 of FIG 1A , with the addition of two proof masses 102c and 102d and various couplers coupling the four proof masses. In particular, the MEMS device 300 includes the first proof mass 102a and the second proof mass 102b, a third proof mass 102c, a fourth proof mass 102d, the substrate 104, tethers 306a-306h, runners 108a, 108b, 108c, 108d, 122a, 122b, 122c and 112d and couplers 114a, 114b, 114c and 114d. Tethers 306a-306h may be of the same type as previously described in connection with tethers 106a-106f or of any other suitable type. The couplers 114a-114d may be of the same type as that previously associated with 1A coupler 114 as described, or of any other suitable type. Runners 108a-108d and 122a-122d may be any of the types of runners described herein.

The sliders 108a-108d and 122a-122d can force linear anti-phase motion of the proof masses 102a-102d parallel to the x and y directions. For example, sliders 108a, 108b and 122a and 122b can force linear anti-phase motion of proof masses 102a-102d parallel to the y-direction. The sliders 108c, 108d, 122c and 122 can force a linear anti-phase movement of the proof masses 102a-102d parallel to the x-direction. However, the movement of the proof masses along the x and y directions can be decoupled from one another.

3A Figure 12 illustrates that in some embodiments, a gyroscope with a proof mass assembly containing four proof masses may include linearly moving balanced sliders on opposite sides of the assembly. As illustrated, the runners may move in the directions indicated by arrows 110a, 110b, 110c and 110d. Impulse-balanced operation can be realized by appropriate selection of the masses such that the combined impulses of the individual masses are offset from one another. For example, runners 108a, 122a, 108b, and 122b may have substantially equal masses and may be arranged to translate in opposite directions (e.g., 108a opposite to 122a and 108b opposite to 122b) such that they move with equal and opposite momenta move and therefore cancel each other out. However, it should be understood that not all embodiments are limited in this regard, as alternative embodiments a MEMS gyroscope may have four masses coupled by runners of the types described herein that are not momentum balanced. For example, in a MEMS gyroscope of one embodiment, sliders 122a-122d may be omitted.

the 3B-3E 10 illustrate in block diagram form various states of anti-phase motion of proof masses 102a-102d 3A in accordance with one non-limiting embodiment. For purposes of discussion, assume that MEMS device 300 is a gyroscope with both drive and sense modes. 3B 10 illustrates, in block diagram form, a first state of linear anti-phase motion of proof masses 102a-102d in a propulsion mode of operation, in accordance with one non-limiting embodiment rich direction to that of the two directly adjacent masses. In the illustrated non-limiting example, proof masses 102a and 102d linearly move in the negative x-direction, while proof masses 102b and 102c linearly move in the positive x-direction. The movement can be synchronous in that movement of one of the proof masses can cause movement of the other.

3C 12 illustrates a second state of anti-phase motion of the drive mode. In this state, proof masses 102a-102d have relative to 3B a reverse direction. Proof masses 102a and 102d move linearly in the x-direction, while proof masses 102b and 102c move linearly in the negative x-direction.

3D 10 illustrates a state of anti-phase motion of proof masses 102a-102d in a measurement mode of operation, in accordance with one non-limiting embodiment. In this non-limiting example, proof masses 102a and 102d linearly move in the y-direction, while proof masses 102b and 102c linearly move in the negative move y-direction. The motion can again be synchronous in that one of the proof masses can cause the other to move.

3E 12 illustrates a second state of anti-phase motion in the measurement mode. In this state, proof masses 102a and 102d move linearly in the negative y-direction, while proof masses 102b and 102c move in the y-direction.

Although the 3B-3E represent linear motion of the proof masses in the top-to-bottom and left-to-right directions, it should be apparent that any combination of such motion can be implemented by a MEMS device. For example, the movement of the proof masses may instead be along a diagonal direction (e.g., at a 45 degree angle to the x and y axes), among other things. For example, the drive axis can be at an angle of 45° to the x-axis and the measurement axis can be at an angle of 135° to the x-axis. Other orientations are also possible. Although the 3B-3C as relating to a drive mode of operation and the 3D 3E described as referring to a measurement mode, it should further be appreciated that the drive and measurement directions may be reversed. In general, it should be obvious that the 3B-3E represent only one example of a linear anti-phase motion that can be implemented by a MEMS device with four moving masses, and that the directions of motion and designations of the drive and measurement modes can take various forms.

Sliders 108a-108d and 122a-122d prioritize anti-phase motion of proof masses 102a-102d while inhibiting spurious modes that can be excited by linear and angular acceleration. Specifically, runners 108a-108b and 122a-122d prioritize anti-phase motion in the y-direction, while runners 108c-108d and 122c-122d prioritize anti-phase motion in the x-direction. As such, the MEMS device 300 may be substantially insensitive or immune to linear and angular acceleration, thereby allowing the MEMS device to operate more accurately as a gyroscope. The sliders can constrain the linear anti-phase motion by mode ordering the modes of the MEMS device such that those modes sensitive to external forces are at much higher frequencies than the desired modes of operation. In this way, jamming modes can be blocked.

the 4A-4B 12 illustrate an example of a synchronized mass gyroscope containing four proof masses in two states of deformation, in accordance with one non-limiting embodiment. 4A 14 depicts a strain condition where the proof masses of the MEMS gyroscope 400 undergo linear anti-phase motion parallel to the x-axis while FIG 4B 12 depicts a strain condition where the proof masses of the MEMS gyroscope 400 experience anti-phase linear motion parallel to the y-axis.

The synchronized mass MEMS gyroscope 400 includes proof masses 402a-402d coupled to sliders 404, respectively. Four pivoting joints 406 are provided for each of the four proof masses. A total of eight runners are provided, including four runners 408 and four runners 410 . Runners 408 are of the type previously described in connection with runners 252a and 252b, and runners 410 are of the type previously described in connection with runners 254a and 254b.

In 4A For example, the synchronized mass MEMS gyroscope is deformed in conjunction with anti-phase linear motion of proof masses 402a-402d parallel to the x-axis. Specifically, proof masses 402a and 402d are translated from their equilibrium positions in the negative x-direction, and proof masses 402b and 402c are translated in the x-direction. As a non-limiting example, this movement may be associated with a drive mode of operation of the MEMS gyroscope. In this state, the runners 408 and 410 on the left and right sides of the proof mass assembly in the directions indicated by the bold arrows. Specifically, the sliders 408 coupling proof masses 402a to 402c and proof mass 402b to 402d are translated in the negative y-direction, and the sliders 410 coupling these proof masses are translated in the y-direction. The runners 408 and 410 coupling the proof mass 402a to 402b and the proof mass 402c to 402d are not displaced in this operating state.

In 4B For example, the synchronized mass MEMS gyroscope is deformed in conjunction with anti-phase linear motion of the proof masses 402a-402d parallel to the y-axis. In particular, proof masses 402a and 402d are translated from their equilibrium positions in the y-direction and proof masses 402b and 204c are translated in the negative y-direction. As a non-limiting example, this movement may be associated with a measurement mode of operation of the MEMS gyroscope. In this state, the sliders 408 and 410 coupling the proof masses 402a to 402b and the proof mass 402c to 402d are displaced in the directions indicated by the bold arrows. Specifically, runners 408 are translated in the x-direction and runners 410 are translated in the negative x-direction. The runners 408 and 410 coupling the proof mass 402a to 402c and the proof mass 402b to 402d are not displaced in this operating state.

From the 4A-4B It should be understood that sliders 408 and 410 can force linear anti-phase motion of proof masses 402a-402d in both the x and y directions, but motion of the proof masses in these two directions is decoupled. Two degrees of freedom are thus provided, thereby ensuring accurate operation of the device as a gyroscope.

Although the MEMS gyroscope 400 with synchronized mass runners previously associated with the 2H and 2I described, it should be apparent that any of the types of runners described herein can be used. For example, instead of runners 408 and 410, the constrained runners of 2L and 2M to be implemented. Thus, the particular implementation of MEMS gyroscope 400 is a non-limiting example of a synchronized mass gyroscope.

4C Figure 12 shows an alternative configuration of a synchronized mass gyroscope. The synchronized mass gyroscope 420 includes four proof masses 402a-402d, the tethers 212, the pivotable joints 406, the runners 408 and 410, the coupler 260 and the slider 422. In this non-limiting example, the runners 408 are connected by the couplers 260 with respective runners 410 coupled. The couplers 260 are from the in 2K shown and have been previously described in connection with that figure. They can be relatively short but allow runners 408 and 410 to move relative to each other. In 4C Each runner 408 is coupled to a respective runner 410 by three couplers 260 . However, other numbers of couplers 260 may be used, including a single coupler 260 coupling a runner 408 to a corresponding runner 410.

In the synchronized mass gyroscope 420 of 4C For example, the pivotable joints 406 are coupled directly to the proof masses rather than through a slider. Here the slide 422 is smaller than the slide 404 of FIG 4A-4B performed, thereby providing the gyroscope 420 with greater angular gain. Angular gain is the ratio of the mass responding to angular rotation to the total modal mass of the measurement mode.

From the foregoing, it should be apparent that aspects of the present application provide synchronized mass gyroscopes. The synchronized mass gyroscopes may include four coupled proof masses configured to linearly move along transverse directions and a plurality of runners disposed at a perimeter of the proof mass assembly and forcing anti-phase linear motion of the proof masses. The runners themselves move linearly and do so in a momentum-balanced manner, such that they have essentially zero net momentum. The runners can decouple a movement of the proof masses parallel to an axis of movement of the proof masses parallel to a second axis. Thus, the drive and measurement modes remain decoupled from each other, while both modes exhibit linear anti-phase motion.

As has been described, aspects of the present application provide MEMS devices that include multiple moveable proof masses coupled by couplers that constrain the proof masses to linear anti-phase motion, and in which the couplers themselves move linearly. The devices may be resonators, gyroscopes, or accelerometers, among other possible devices. Various systems can use such components. Accordingly, various aspects of the present application provide MEMS devices with runners of the types described herein, the devices in different areas used to detect rotation including but not limited to sports, healthcare, military and industrial applications. Some non-limiting examples will now be described.

A system employing a MEMS device of the types described herein may include a power source coupled to the device, processing circuitry (e.g., sensing circuitry) configured to process electrical signals generated by the device to produce a feature derived from Interest is included to evaluate such as rotation, and/or communication circuitry for communicating with external devices, wirelessly or through a wired connection. Such components can be combined into a single housing, thereby providing an integrated product.

MEMS devices of the types described herein can be used in a wide variety of devices, products, and fields. One such area is in vehicles such as automobiles, watercraft, and aircraft. 5 Figure 12 illustrates an example in which a MEMS device of the types described herein is deployed in a car. In the example of 5 An automobile 500 includes a controller 502 coupled by a wired or wireless link 506 to an onboard computer 504 of the automobile. Control unit 502 may include a MEMS sensor or device of the types described herein, optionally along with a power source, processing circuitry, interface circuitry for communication via link 506, or any other suitable components. As a non-limiting example, controller 502 may include a MEMS gyroscope of the types described herein. As an example, the MEMS gyroscope may detect yawing of the automobile 500 . The control unit 502 may comprise a package or housing that is attached to an appropriate part of the automobile 500 with the MEMS device therein. The controller 502 may receive power and control signals from the onboard computer 504 and provide measurement signals to the onboard computer 504 .

Another area where MEMS devices of the types described herein can be used is in sensor devices for sports applications such as tennis, swimming, running, baseball, or hockey, among others. In some embodiments, a MEMS gyroscope of the types described herein may be part of a wearable fitness device. In other embodiments, the sensor may be part of a piece of sports equipment, such as part of a tennis racket, baseball bat, or hockey stick. Measurement data from the sensor can be used to evaluate the user's performance.

Various embodiments described thus far have illustrated the operation of gyroscopes in relation to detecting in-plane rotation of proof masses. Such gyroscopes are referred to as yaw gyroscopes. However, the use of cursors as described herein can also be applied to gyroscopes that detect other forms of rotation in addition to or as an alternative to detecting yaw. For example, gyroscopes that detect both yaw and pitch, both roll and pitch, or all three, yaw, roll and pitch, can use sliders of the types described herein that couple multiple proof masses together and move in response to anti-phase movement of the proof masses move linearly translationally. Thus, it should be understood that the embodiments described herein that pertain to gyroscopes are not limited as to the type of gyroscope provided.

Various embodiments described thus far provide MEMS gyroscopes with linearly moving couplers that couple two or more proof masses of the gyroscope together. Such couplers can be used with multiple mass cavities. Thus, aspects of the present application provide resonators with multiple proof masses coupled together by linearly moving couplers.

Aspects of the present application provide MEMS devices (e.g., gyroscopes, accelerometers, and resonators) that possess various beneficial properties, at least some of which have previously been described. It should be understood that not all aspects of the application necessarily provide every benefit, nor are benefits limited to those described herein. Some examples will now be described.

In accordance with aspects of the present application, multiple proof mass MEMS devices are provided that have a low level of acceleration sensitivity (which can also be described as acceleration insensitive). Thus, for example, gyroscopes can have extremely accurate performance with respect to rotation detection. Some aspects of the present application provide MEMS gyroscopes that operate in an anti-symmetric manner in both drive and sense modes. Aspects of the present application provide MEMS gyroscopes that are in addition to those described above advantages are relatively insensitive to phase quadrature. Furthermore, the manufacture of such devices, including runners, can be relatively easy and accurate compared to the manufacture of other types of couplers. Thus, high-precision MEMS devices possessing high-precision synchronous anti-phase motion, even with manufacturing errors associated with typical micro-fabrication techniques, can be realized.

According to one embodiment, there is provided a synchronized ground balanced MEMS gyroscope, comprising: a substrate, first, second, third, and fourth proof masses suspended over and coupled to the substrate and each configured to rotate translate linearly parallel to the first and second axes; and means for forcing linear anti-phase motion of the four proof masses parallel to the first axis.

The balanced synchronized mass MEMS gyroscope, in some embodiments, includes a means for forcing linear anti-phase motion of the four proof masses parallel to the second axis.

The means for forcing linear anti-phase motion of the four proof masses parallel to the first axis and the means for forcing linear anti-phase motion of the four proof masses parallel to the second axis includes, in some embodiments, means for providing momentum-balanced operation of the balanced synchronized-mass MEMS gyroscope.

The balanced synchronized mass MEMS gyroscope, in some embodiments, further comprises means for blocking phase quadrature of the four proof masses.

The balanced synchronized mass MEMS gyroscope, in some embodiments, further comprises means for blocking phase quadrature of the four proof masses.

According to one embodiment, there is provided a multi-mass balanced MEMS device, comprising: a substrate, a first proof mass coupled to the substrate by a first tether and configured for linear motion; a second proof mass coupled to the substrate by a second tether and configured for linear movement; and a first coupler coupling the first and second proof masses together and configured to move linearly when the first proof mass moves in a first direction and the second proof mass moves in a second direction opposite the first direction.

In some embodiments, the first and second proof masses at least partially define a proof mass assembly, wherein the first coupler is disposed on a first side of the proof mass assembly, and wherein the balanced multi-mass MEMS device further includes a second coupler disposed on an opposite side of the first side second side of the proof mass assembly and configured for linear motion opposite to the first coupler when the first and second proof masses exhibit anti-phase linear motion.

The balanced multi-mass MEMS device, in some embodiments, further includes a second coupler that couples the first and second proof masses together and for linear movement opposite to the first coupler when the first proof mass moves in the first direction and the second moves Proof mass moves in the second direction opposite the first direction, is formed. In some embodiments, the first and second couplers are coupled on the same side of the first proof mass.

In some embodiments, the first and second proof masses at least partially define a proof mass assembly, and the balanced multi-mass MEMS device further includes third and fourth couplers on opposite sides of the proof mass assembly from the first and second couplers, the third coupler being configured thereto is to linearly move in a same direction as the first coupler and the fourth coupler is adapted to linearly move in a same direction as the second coupler when the first proof mass moves in the first direction and the second Proof mass moves in the second direction opposite to the first direction.

In some embodiments, the first and second couplers are linearly arranged with respect to each other.

In some embodiments, the first coupler is proximate to the first and second proof masses and the second coupler is distal to the first and second proof masses.

In some embodiments, the balanced multi-mass MEMS device further includes a pivotable hinge positioned between the first coupler and the first proof mass is coupled, the first coupler being adapted to move linearly as the pivotable joint pivots.

In some such embodiments, the balanced multi-mass MEMS device further includes a moveable slider pivoted to the pivoting hinge and disposed between the pivoting hinge and the first proof mass.

According to one embodiment, there is provided a method of operating a multi-mass balanced MEMS device, comprising: linearly moving a first proof mass and a second proof mass in anti-phase motion; and linearly translating a first coupler coupling the first and second proof masses when the first and second proof masses linearly translate in anti-phase motion.

In some embodiments, the first and second proof masses at least partially define a proof mass assembly, the first coupler being disposed on a first side of the proof mass assembly, and the method further comprising linearly translating a second coupler in a direction opposite to the first coupler when the linearly moving first and second proof masses in anti-phase motion, wherein the second coupler is disposed on a second side of the proof mass assembly opposite the first side.

In some embodiments, the method of operating the balanced multi-mass MEMS device further comprises linearly translating a second coupler coupling the first and second proof masses in a direction opposite to the first coupler when the first and second proof masses linearly translate in anti-phase motion move.

In some embodiments, the first and second proof masses at least partially define a proof mass assembly, and wherein the balanced multi-mass MEMS device further comprises third and fourth couplers on opposite sides of the proof mass assembly from the first and second couplers, and the method further linearly translating the third coupler in the same direction as the first coupler and linearly translating the fourth coupler in a same direction as the second coupler when the first and second proof masses move in anti-phase linear motion.

In some embodiments of the method, linearly translating the first and second couplers comprises linearly translating the first and second couplers along a common axis.

In some embodiments of the method of operating the balanced multi-mass MEMS device, linearly translating the first and second couplers comprises linearly translating the first coupler along an axis proximate to the first and second proof masses and the second coupler along an axis distal to the first and the second proof mass.

In some embodiments, the method further comprises pivoting a pivotable joint between the first coupler and the first proof mass while the first coupler linearly translates.

In some embodiments, the method further comprises linearly translating a slider coupled to the pivoting joint and disposed between the pivoting joint and the first proof mass.

According to one embodiment, there is provided a multi-mass balanced MEMS device, comprising: a substrate; a first proof mass coupled to the substrate by a first tether and configured for linear motion; a second proof mass coupled to the substrate by a second tether and configured for linear movement; and means for blocking in-phase linear motion of the first and second proof masses.

In some embodiments, the means for blocking in-phase linear motion of the first or second proof masses constrains the first and second proof masses to anti-phase linear motion.

In some embodiments, the means for blocking in-phase linear motion of the first and second proof masses comprises means for blocking rotation of the first and second proof masses.

In some embodiments, the balanced multi-mass MEMS device further comprises a means for blocking phase quadrature coupled to the means for blocking in-phase linear motion of the first of the second proof masses.

The terms "approximately" and "about" may be used to mean within +20% of a target value in some embodiments, within ±10% of a target value in some embodiments, within ±5% of a target value in some embodiments, and nevertheless be within +2% in some embodiments. The terms "approximately" and "about" may include the target value.

Claims (16)

A synchronized ground MEMS device comprising: a substrate; a first proof mass coupled to the substrate by a first tether and configured for linear movement parallel to both the first and second transverse axes; a second proof mass coupled to the substrate by a second tether and configured for linear movement parallel to both the first and second transverse axes; and a first coupler coupling the first and second proof masses together and configured to linearly move parallel to the first axis and constrain movement of the first and second proof masses to synchronous, anti-phase linear movement such that when the first proof mass moves in a first direction parallel to the second axis, the second proof mass moves in a second direction parallel to the second axis, opposite the first direction. MEMS device claim 1 further comprising a third proof mass coupled to the substrate by a third tether and configured for linear movement parallel to both the first and second transverse axes; a fourth proof mass coupled to the substrate by a fourth tether and configured for linear movement parallel to both the first and second transverse axes; and a second coupler coupling the third and fourth proof masses together and configured to linearly move parallel to the first axis and constrain movement of the third and fourth proof masses to synchronous, anti-phase linear movement such that when the third proof mass moves in the second direction parallel to the second axis, fourth proof mass moves in the first direction parallel to the second axis. MEMS device claim 2 , wherein the first and second couplers are configured to move linearly in opposite directions. MEMS device claim 2 , wherein the first and second couplers are adapted to move linearly in the same direction. MEMS device claim 2 , further comprising a third coupler coupling the first and third proof masses together and a fourth coupler coupling the second and fourth proof masses together, the third and fourth couplers being configured to linearly parallel the second axis move when the first and third proof masses move linearly in anti-phase motion parallel to the first axis and the second and fourth proof masses move linearly in anti-phase motion parallel to the first axis. The MEMS device of any preceding claim, further comprising a further coupler coupling the first and second proof masses, the first and further couplers being linearly arranged with respect to one another. MEMS device claim 2 , wherein the MEMS device includes a plurality of couplers including the first coupler, and wherein the plurality of couplers are configured to collectively constrain anti-phase linear motion of the four proof masses parallel to the first axis and anti-phase linear motion of the first and second proof masses parallel to the to constrain the second axis, and wherein the couplers of the plurality of couplers are configured as linearly moving sliders. MEMS device claim 7 wherein the couplers of the plurality of couplers have masses selected so that together they provide substantially zero net momentum when linearly translating. A method of operating a synchronized mass MEMS device having four proof masses coupled together, the method comprising: moving first and second proof masses of the four proof masses in anti-phase linear motion parallel to a first axis; moving third and fourth proof masses of the four proof masses in anti-phase linear motion parallel to the first axis; linearly translating a first coupler coupling first and second proof masses of the four proof masses to constrain the first and second proof masses to anti-phase linear motion parallel to the first axis; and linearly translating a second coupler comprising the third and fourth proof masses coupling the four proof masses to constrain the third and fourth proof masses to anti-phase linear motion parallel to the first axis. procedure after claim 9 wherein linearly translating the first coupler and linearly translating the second coupler comprises linearly translating the first and second couplers parallel to a second axis transverse to the first axis. procedure after claim 9 wherein linearly translating the first coupler and linearly translating the second coupler comprises linearly translating the first and second couplers in opposite directions. procedure after claim 9 , further comprising moving the first and third proof masses in anti-phase linear motion parallel to a second axis transverse to the first axis, moving the second and fourth proof masses in anti-phase linear motion parallel to the second axis, linearly translating a third coupler, the couples the third proof mass to the first proof mass when the first and third proof masses move in anti-phase linear motion parallel to the second axis, and linearly translating a fourth coupler that couples the fourth proof mass to the second proof mass when the second and move the fourth proof mass in antiphase linear motion parallel to the second axis. procedure after claim 9 comprising linearly translating a plurality of couplers comprising the first and second couplers in momentum-balanced operation. procedure after claim 9 , 10 , 11 or 12 , wherein moving the first and second proof masses in anti-phase linear motion parallel to the first axis and moving the third and fourth proof masses in anti-phase linear motion parallel to the first axis comprises driving the four proof masses, the method further comprising detecting a rotation of the MEMS device with synchronized mass by moving the first and third proof masses in anti-phase linear motion parallel to a second axis transverse to the first axis and moving the second and fourth proof masses in anti-phase linear motion parallel to the second axis, and the method further comprises forcing a anti-phase linear motion of the first and second proof masses along the first axis; and forcing the first and third proof masses to anti-phase linear motion along the second axis using a plurality of linearly translating couplers. procedure after claim 9 , 10 or 11 , further comprising linearly translating a third coupler that couples the first and second proof masses in a direction opposite to that in which the first coupler is translated. Balanced MEMS gyroscope with synchronized mass, comprising a MEMS device according to any one of Claims 1 until 8th .

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