MEMS Sensor Annular Mass Structure for Vibration Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing sensors with MEMS structures face challenges in improving their characteristics, such as noise suppression and accuracy in detecting external forces, particularly due to limitations in mass distribution and vibration stability.
Innovation Solution
The sensor design includes a movable portion with a plurality of annular portions, connect portions, and a first structure that functions as a mass member, providing increased mass and stability. The first structure is connected to the outermost annular portion, allowing for a longer radial length and enhanced vibration characteristics.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If the movable portion has a conventional structure without extended first structures, then the device complexity is low, but the mass distribution is insufficient and vibration stability is poor
Solution Approach 1:
The movable portion is segmented into multiple annular portions (first, second, third annular portions) arranged concentrically, with first structures extending radially from each. This segmentation allows independent optimization of each segment's mass distribution while maintaining overall structural coherence, improving vibration stability without excessive complexity
Solution Approach 2:
The first structures extend in the radial direction (third dimension) from the annular portions, adding mass distribution in a new spatial dimension. This radial extension creates a more distributed mass pattern that enhances vibration stability while keeping the overall structure manageable
2Measurement precision
If the first structures are made longer in the radial direction, then the mass distribution improves and vibration stabilizes, but the manufacturing precision requirements increase
Solution Approach 1:
The first structures have different lengths at different radial positions - longer at the outer end and shorter at the inner end connected to the base. This local variation in quality allows optimization of mass distribution for detection accuracy while keeping manufacturing feasible through gradual length transitions rather than uniform extreme dimensions
Solution Approach 2:
The first structures are nested within the radial space between the base and the outer annular portion, with each structure extending from an inner annular portion toward the outer annular portion. This nesting arrangement maximizes mass distribution within available space while maintaining compact overall dimensions that are easier to manufacture
3Stability of the object's composition
If the movable portion has increased mass through additional structures, then the vibration stability improves, but the mass of the moving object increases
Solution Approach 1:
Mass is concentrated locally at specific positions where first structures extend from annular portions, rather than uniformly distributing mass throughout. This localized mass addition provides vibration stability through strategic moment of inertia enhancement while minimizing overall mass increase compared to uniform thickening approaches
Solution Approach 2:
Instead of increasing mass by thickening annular portions in the plane, the first structures extend in the radial direction (third dimension), creating mass distribution through vertical extension rather than horizontal expansion. This dimensional approach provides stability with more efficient mass utilization
Data Source
AI summary
According to one embodiment, a sensor includes a base including a first face, a fixed portion fixed to the first face, and a movable portion supported by the fixed portion. The movable portion includes a plurality of annular portions, a plurality of connect portions, and a first structure. Each of the plurality of annular portions is provided around the fixed portion with the fixed portion as a center in a first plane along the first face. One of the plurality of connect portions connects two of the plurality of annular portions to each other. The plurality of annular portions include a first annular portion. The first annular portion is outermost of the plurality of annular portions. The first structure is connected to the first annular portion. The first annular portion is provided between the fixed portion and the first structure.