Automated Design and Prototyping of Macro and Micro Compliant Mechanisms

1. Automated Design and Prototyping of Macro and Micro Compliant Mechanisms Compliant mechanism concept leads to a clean separation of design/modeling from manufacturing/assembly activities. The objective of this research is to provide a link between the two through efficient data translations and automated reverse engineering techniques. Objectives Optimal topology design of compliant mechanisms Automatic image interpretation and creation of solid model from optimized topology image Reverse engineering for microfabricated artifacts Image processing for edge-extraction and object-finding Writing IGES file for Pro-Engineer Macro prototyping using Stratasys FDM 1650 rapid prototyping system Micro prototyping using MCNC’s Multi-User-MEMS-Processes (MUMPs) Automated metrology for a ceramic meso-scale machining

2. Performance Specifications Synthesis Solution Refined Design Solution Reverse Engineering Meshed Model for Analysis Solid Model from the Optimized Device CAD model from the macro prototype Design Mask Layout for Microfab. Digital Format for SFF or CNC Refined Prototype Digital Interface Macro Prototype Micro Prototype Solid model from microscopic images Fabrication/Prototyping Design and Prototyping of Macro & Micro Compliant Mechanisms

4. Edge Extraction from 2-D Images Image from the optical microscope After edge extraction

5. Edge Extraction from 2-D Images Image from the optical microscope After edge extraction The lack of sharp edges corresponding to the actual structure poses a challenge in extracting the correct topology.

6. Verification with Test Images Extracted circular segments ported into Pro-E in IGES format Test image with circular curves Extracted line segments ported into Pro-E in IGES format Test image with sharp edges

7. Experimental Set-up for Optical Imaging

8. From Fabricated MEMS Device to a Solid Model Optical microscope image of a compliant micro crimper After edge extraction 5 µm

9. From Fabricated MEMS Device to a Solid Model (cont’d) Extruded solid model ready for analysis IGES model exported into Pro-E with line and arc segments

10. From Fabricated MEMS Device to a Solid Model (cont’d) FDM prototype of compliant gripper Unloaded configuration Deformation under loading

11. From Optimized Compliant Topology Image to a Solid Model Topology optimization does not give the shape precisely in both the “super structure” and “material density” approaches. Designer’s intuition is needed to interpret the image and to obtain a manufacturable form. Simple image processing is inadequate to capture the correct quantitative behavior of the optimized compliant topology. Future Tasks Use shape optimization to refine the topology image with stress and manufacturability constraints. Combine image processing with shape optimization to automate the entire process.

12. From Optimized Compliant Topology Image to a Solid Model Optimized compliant topology using material density design parameterization IGES model with line and arc segments Image processing, edge extraction, and object finding

13. From Optimized Compliant Topology Image to a Solid Model Solid model ready for rapid prototyping and/or detailed 3-D analysis Suitable flexibility is not obtained.