3D Printed Micro-Scale Mechanical Testing Fixture
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional mechanical testing systems for micro-scale specimens are expensive, time-consuming to fabricate, and limited in their ability to measure mechanical properties in specific force ranges, particularly in the nano-scale regime, due to costly fabrication methods and proprietary software requirements.
Innovation Solution
A 3D printed mechanical testing system with a linear actuator, cameras for digital image correlation, and a data-acquisition system, allowing for sample-specific force range tuning and high-throughput analysis, using rapid 3D printing methods with polylactic acid to fabricate fixtures with customizable force-displacement ranges.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If conventional fabrication methods (waterjet or wire electro discharge machining) are used to create micro-scale test systems, then manufacturing precision is improved, but device complexity and cost increase significantly
Solution Approach 1:
The patent employs disposable, low-cost fixtures made from materials like acrylic or aluminum that can be rapidly fabricated using simple machining or 3D printing. These fixtures are designed for single-use or limited-use applications, eliminating the need for expensive, precision-engineered permanent fixtures. The fixtures include features like specimen mounting blocks, alignment pins, and load application points that are sufficient for micro-scale testing without requiring high manufacturing precision.
Solution Approach 2:
The patent replaces complex mechanical measurement systems with optical measurement methods. Instead of using precision mechanical extensometers or strain gauges that require complex mounting and calibration, the system uses digital image correlation (DIC) with cameras to measure displacement and strain. This substitution eliminates the need for precision mechanical components while maintaining measurement accuracy.
2Measurement precision
If proprietary software is required for interfacing with test systems, then measurement precision is improved, but ease of operation deteriorates
Solution Approach 1:
The patent implements self-service capabilities through open-source software that performs automatic calibration and data analysis. The system includes built-in routines for calibrating force sensors using known weights, automating the DIC image processing, and generating stress-strain curves without user intervention. This eliminates the need for proprietary software while maintaining measurement precision through automated quality control.
Solution Approach 2:
The patent uses universal, open-source software platforms (such as Python with libraries like OpenCV for image processing and NumPy for data analysis) that can perform multiple functions including force calibration, displacement measurement, strain calculation, and data visualization. This multi-functional software replaces the need for separate proprietary applications, improving ease of operation while maintaining measurement accuracy.
3Manufacturing precision
If MEMS-based methods are used for nano-scale testing, then manufacturing precision is improved, but loss of time increases due to costly fabrication processes
Solution Approach 1:
The patent segments the testing system into separate functional components: a simple fixture for specimen mounting, a linear actuator for load application, and an optical system for measurement. This segmentation allows each component to be fabricated independently using appropriate methods (simple machining for fixtures, commercial off-the-shelf actuators, and standard cameras), avoiding the need for time-consuming integrated MEMS fabrication while maintaining the required precision for each function.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Enables cost-effective, rapid fabrication of mechanical testing fixtures that provide well-controlled mechanical force measurements and stress-strain curves for micro-scale systems, reducing errors and increasing throughput in mechanical property analysis.
Implementation Method 1
the first side includes force sensing beams extending perpendicular to the axis of movement
Implementation Method 2
a linear actuator having an axis of movement
Implementation Method 3
two cameras; a data-acquisition system configured to acquire data from the linear actuator, the controller, and the two cameras
Data Source
AI summary
A system for mechanical testing a specimen includes a 3D printed mechanical testing fixture; a linear actuator having an axis of movement; a controller configured to control the linear actuator; two cameras; a data-acquisition system configured to acquire data from the linear actuator, the controller, and the two cameras; and the specimen. The specimen is marked in two locations with tracking markers to provide indication to the data acquisition system via at least one camera of movement and change in length of the specimen. The fixture includes force-sensing beams extending perpendicular to the axis of force.