【MEMS】🧠 01. Design Philosophy and Overall Architecture of mems-ana
A Lightweight ROM-Based Analysis Tool for MEMS
topics: [“MEMS”, “analysis”, “ROM”, “Python”, “simulation”]
📌 Introduction
In MEMS (Micro Electro Mechanical Systems) design,
analysis is indispensable because structure, materials, and actuation methods are tightly coupled.
At the same time, rigorous FEM-based analysis often comes with drawbacks:
- Time-consuming model construction
- Heavy parameter studies
- Excessive complexity for early-stage design exploration
This article introduces the lightweight MEMS analysis tool mems-ana, developed with these challenges in mind, and provides a high-level overview of:
- The design philosophy behind it
- What it is intended to do
- What it deliberately chooses not to do
🧩 What Is mems-ana?
mems-ana is a lightweight MEMS analysis tool based on Reduced Order Models (ROMs).
Its primary goals are:
- To complement, not replace, FEM
- To support sensitivity analysis and behavioral understanding in early design stages
- To serve as a tool for education, PoC development, and design thinking training
Rather than pursuing maximum accuracy, mems-ana prioritizes:
Lightweight computation, speed, and structural interpretability
🧮 Why ROM?
Many MEMS structures share common characteristics:
- Thin-film structures
- Simple geometries (rectangular, circular)
- A small number of dominant modes
In such cases, displacement $u(x,y,t)$ can be expressed as:
\[u(x,y,t) = \sum_{n} q_n(t)\,\phi_n(x,y)\]That is, the essential behavior can be captured by a limited set of modes.
mems-ana is built on this assumption:
- The number of modes is intentionally restricted
- The system is reduced to physically meaningful degrees of freedom
This enables a balance between computational efficiency and interpretability.
🔀 Division of Roles with FEM
mems-ana does not reject FEM.
Instead, it emphasizes clear separation of roles.
| Aspect | mems-ana | FEM |
|---|---|---|
| Early-stage design | ◎ | △ |
| Sensitivity / trend analysis | ◎ | ○ |
| Higher-order modes | △ | ◎ |
| Local stress evaluation | × | ◎ |
| Computational cost | Light | Heavy |
mems-ana is a tool for answering:
“Why does this structure behave this way?”
— quickly and structurally.
⚙️ What mems-ana Can Do (Overview)
mems-ana supports analyses such as:
- Natural frequencies and mode shapes (simplified)
- Voltage–displacement (V–u) characteristics
- Static and quasi-static response under piezoelectric actuation
- Visualization of spatial displacement distributions
- Time-domain response and animation
All of these are implemented with:
- Python-based code
- Explicit modeling assumptions
- A structure where equations and implementation remain traceable
🚫 Deliberate Limitations (Important)
mems-ana includes intentional constraints:
- No nonlinear large-deformation analysis
- No evaluation of local stress concentration
- No attempt to reproduce all real-device phenomena
Instead, it focuses on:
- Making assumptions explicit
- Limiting the meaning of calibration parameters
- Clearly defining the valid operating range
Deciding what not to do is a critical part of tool design.
🧩 Relation to Education, PoC, and AITL
mems-ana is not intended as a standalone solver.
It is designed to be used in contexts such as:
- Educational tools (physics and design thinking)
- PoC evaluation of design ideas
- AITL (Architecture for Integrated Technology Logic), as a means of structuring design knowledge
In particular, mems-ana emphasizes:
- Human-interpretable models
- Consistency from equations → implementation → visualization
These are prerequisites for intelligence and automation, not optional extras.
🔗 GitHub Repository
The source code and demos for mems-ana introduced in this article are available at:
https://github.com/Samizo-AITL/mems-ana
📚 About This Series
This article is the first installment in the mems-ana series.
- 01: Design philosophy and overview (this article)
- 02: Visualization demos (piezo hysteresis and butterfly displacement)
- 03: Mathematical structure of
mems-ana_coreand ROM design
The next article will focus on
“how it actually behaves” through concrete visualization examples.
📝 Closing Remarks
mems-ana is designed not as:
“a tool to produce the correct answer,”
but as:
“a tool to think with.”
If this article helps convey that lightweight analysis can be a valid and powerful option for early-stage design exploration and hypothesis testing, it has served its purpose.