Fully decoupled three-axis MEMS gyroscope
Provided is a fully decoupled MEMS gyroscope, including a base, a sensing unit elastically connected to the base, and a driving unit coupled with the sensing unit and driving the sensing unit to move. The base includes a coupling anchor point located at a center of a rectangle and a coupling structure elastically connected to the coupling anchor point. The driving unit includes four driving members located at inner positions of four corners of the rectangle. The sensing unit includes two X mass blocks symmetrically arranged in two of the avoiding intervals, two Y mass blocks symmetrically arranged in the other two of the avoiding intervals, four Z mass blocks elastically connected to the adjacent driving members and located at the four corners of the rectangle, and four Z detection decoupling members elastically connected to the adjacent Z mass blocks and elastically connected to each other around the rectangle.
1 . A decoupled three-axis MEMS gyroscope, the decoupled three axis MEMS gyroscope is in the shape of a rectangle; comprising:
a base, comprising:
a coupling anchor point located at a center of the rectangle; and
a coupling structure elastically connected to the coupling anchor point;
a driving unit coupled with a sensing unit and driving the sensing unit to move, comprising:
four driving members respectively located at inner positions of four corners of the rectangle and elastically connected to the base, wherein the four driving members are all frame-shaped and annularly and symmetrically arranged around the coupling anchor point, and an avoiding interval is formed between adjacent driving members; and
the sensing unit elastically connected to the base, comprising:
two X mass blocks symmetrically arranged in two of the avoiding intervals oppositely arranged and each X mass block is elastically connected to the coupling structure and two of the four driving members are located on both sides of one of the X mass blocks;
two Y mass blocks symmetrically arranged in the other two of the avoiding intervals oppositely arranged and each Y mass block is elastically connected to the coupling structure and two of the four driving members are located on both sides of one of the Y mass blocks;
four Z mass blocks are located at the four corners of the rectangle, and each Z mass block is connected to one of the four driving members located at the corresponding corner of the rectangle; and
four Z detection decoupling members respectively elastically connected to the adjacent Z mass blocks and arranged around the rectangle,
wherein the adjacent Z detection decoupling members are elastically connected;
each Z mass block is located on an outside of each driving member away from the coupling anchor point, and each Z detection decoupling member is located on an outside of each Z mass block away from the coupling anchor point;
wherein the base further comprises side anchor points;
two sides of a top of each Z detection decoupling member are both extended to form a third flexible beam whose middle portion is connected to each side anchor point, and the middle portion of each third flexible beam is extended toward a groove opened inside each side anchor point to form a bent portion;
wherein an end of each X mass block away from the coupling structure and an end of each Y mass block away from the coupling structure is provided with a lateral slit;
the base further comprises intermediate structures spaced apart from a side of each X mass block away from the coupling structure or a side of each Y mass block away from the coupling structure, and each X mass block and each Y mass block are both extended toward the lateral slit to form a lateral flexible beam connected to the intermediate structure;
the end of each third flexible beam away from the Z detection decoupling member is connected to one of the intermediate structure;
both sides of each driving member are both extended along a direction of a space between each Z mass block and each X mass block or each Y mass block to form two fourth flexible beams of corresponding ones of the side anchor points, the end of each of the two fourth flexible beams away from the corresponding driving member is connected to one of the intermediate structures.
2 . The decoupled three-axis MEMS gyroscope of claim 1 , wherein the coupling structure comprises an inner coupling ring coupled with the coupling anchor point, and an outer coupling ring coupled with the inner coupling ring; an inner side of the inner coupling ring extends along a direction of a center line of the rectangle to form two inner coupling beams connected to the coupling anchor point, and an inner side of the outer coupling ring extends along a straight line perpendicular to the two inner coupling beams to form two outer coupling beams connected to the inner coupling ring.
3 . The decoupled three-axis MEMS gyroscope of claim 2 , wherein a first connecting beam with a bent portion is formed at a position of each X mass block and each Y mass block that is close to the corresponding coupling structure and is extended toward the outer coupling ring, and an end of the first connecting beam away from the driving member is connected to an outer wall of the corresponding outer coupling ring.
4 . The decoupled three-axis MEMS gyroscope of claim 2 , wherein the base further comprises connecting beam anchor points, and outer walls of the two corners of one end of each driving member close to the connecting beam anchor point are both extended outward to form a second connecting beam; and the second connecting beam is connected to the connecting beam anchor point, and each second connecting beam is located in a space between an outer wall of each driving member and the connecting beam anchor point.
5 . The decoupled three-axis MEMS gyroscope of claim 4 , wherein the X mass blocks and the Y mass blocks are each provided with a groove, and a groove wall of each groove is extended outward to form a guide beam, and an end of the guide beam away from the groove wall is connected to the connecting beam anchor point.
6 . The decoupled three-axis MEMS gyroscope of claim 2 , wherein each driving member is parallel to each Z mass block, and two sides of an outer wall of each driving member close to one end of each Z mass block are both extended to form a first flexible beam; an end of each first flexible beam away from each driving member is connected to each Z mass block, and each first flexible beam is located in a space between the outer wall of each driving member and each Z mass block.
7 . The decoupled three-axis MEMS gyroscope of claim 6 , wherein each Z detection decoupling member is in a shape of a frame, which is parallel to the Z mass block and is arranged outside each Z mass block and is spaced apart from the Z mass block to form a slit; outer walls of both ends of each Z detection decoupling member facing a corresponding one of the driving members are both extended outward to form a third connecting beam connected to each Z mass block; each third connecting beam is located in a space between each Z detection decoupling member and each Z mass block; the base further comprises decoupling member anchor points located in a space between each Z detection decoupling member and each Z mass block and located at both ends of the Z mass block, and two sides of each Z detection decoupling member are both extended outward to form a second flexible beam with a bent portion and connected to each decoupling member anchor point.
8 . The decoupled three-axis MEMS gyroscope of claim 1 , wherein a driving transducer is arranged in each driving member; wherein X-plane detection transducers are arranged symmetrically above the X mass blocks; wherein Y-plane detection transducers are arranged symmetrically above the Y mass blocks; and a Z-plane detection transducer is arranged in each Z mass block.