Orthogonal MEMS IMU Packages with Mechanical Interconnects
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing inertial measurement units (IMUs) face challenges in achieving accurate and stable mutual orthogonality between MEMS sensors, leading to increased size and cost due to the need for complex mounting structures and potential material mismatches, which can result in performance issues like differential thermal expansion.
Innovation Solution
A method of manufacturing IMUs where individual MEMS inertial sensor packages are directly orthogonally mounted to each other using mechanical interconnect features, eliminating the need for an underlying mounting block and allowing for uniform material composition, enabling accurate mechanical stability and reduced component count through layer-by-layer fabrication and interlocking designs.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If MEMS sensors are mounted on a ceramic or polymeric support structure, then electrical connections and mechanical mounting are provided, but the system size increases and achieving accurate mutual orthogonality becomes difficult
Solution Approach 1:
The patent merges the mounting structure with the sensor packages themselves by integrating mechanical interconnect features directly into each package. This eliminates the need for a separate host structure, reducing overall system complexity while maintaining accurate orthogonal alignment through the interlocking features built into each package.
Solution Approach 2:
The patent extracts the mounting function from the traditional host structure and relocates it to the sensor packages themselves. By taking out the separate mounting block and integrating its functionality into the packages, the system achieves simpler construction while preserving the ability to maintain precise orthogonal relationships.
2Reliability
If a ceramic or polymeric host structure is used to mount MEMS sensors, then mechanical mounting and electrical connections are achieved, but material mismatch causes differential thermal expansion and performance problems
Solution Approach 1:
The patent applies homogeneity by using identical ceramic materials for both the packages and the host structure. This eliminates material mismatch between dissimilar materials (ceramic to plastic/composite), thereby preventing differential thermal expansion and the associated performance problems while maintaining reliable thermal stability.
3Measurement precision
If three or six individual single axis inertial sensors are used for high performance multi-axis systems, then measurement capability is achieved, but system size and cost increase significantly
Solution Approach 1:
The patent merges multiple single-axis sensor functions into integrated multi-axis sensor packages. By combining three or six individual single-axis inertial sensors into unified packages with orthogonal mounting capabilities, the system achieves the required measurement precision for multi-axis detection while reducing the number of separate components and simplifying the overall system architecture.
Data Source
Figure 1a~1b
Figure 2a~2c
Figure 3~4f
AI summary
A method of manufacturing an inertial measurement unit (IMU) 900 comprises fabricating a plurality of individual MEMS inertial sensor packages 902 at a package level as sealed packages 902 containing a MEMS inertial sensor chip 214 and an integrated circuit 212 electrically connected together. Fabricating the individual MEMS inertial sensor packages 902 comprises forming mechanical interconnect features 104 in each package 902 and assembling the IMU 900 by mechanically interconnecting each individual MEMS inertial sensor package 902 with another individual MEMS inertial sensor package 902 in a mutually orthogonal orientation.