Frequently Asked Questions
General
What analysis types does deFlex support?
deFlex offers six analysis types:
- Compliant Mechanism 2D / 3D: Design optimization for mechanisms that transmit force and motion through elastic deformation.
- Flexure: Optimization for flexure elements such as hinges and springs.
- Decoupled Flexure: Two-stage optimization for flexures that accommodate thermal expansion, using thermal pre-computation followed by design optimization.
- Metamaterials: Periodic unit-cell optimization for architected materials with tailored mechanical properties.
- Planar Decomposition: Decomposition of 3D problems into 2D cross-sections for faster analysis.
See the Analysis Types reference for full details on each type.
Do I need to install anything?
No. deFlex runs entirely in the browser. The solver runs server-side, so you do not need a powerful local machine. A modern browser (Chrome, Firefox, Safari, or Edge) on any operating system is sufficient.
What coordinate system does deFlex use?
deFlex uses a Z-up coordinate system (engineering convention). Width is along X, height is along Y, and depth (for 3D) is along Z. This differs from the Y-up convention used by some 3D tools, but deFlex handles the conversion internally.
Is my data saved automatically?
Yes. Scenes are saved to the cloud automatically as you work. All changes to preserves, settings, and solver runs are persisted. You can close the browser and return to your scene later from the home page.
Geometry
What file formats can I import?
deFlex supports STEP files (.step, .stp) for design domain geometry. Both AP203 and AP214 formats are supported. STEP files are parsed client-side and then uploaded to the server.
For certain preserve types (deformation step), STL files are also supported.
Can I use 3D geometry for 2D analysis?
Yes. When you import a 3D STEP file into a 2D analysis, deFlex prompts you to select a computation face. The solver extracts that face as a 2D cross-section and runs the optimization on it. This is common for analyzing mounting plates where the geometry was modeled as a 3D solid.
What is the maximum geometry size?
There is no hard limit on domain dimensions, but practical limits exist:
- Mesh resolution: A 1000 x 1000 mm domain at 1.0 mm element size produces 1,000,000 elements, which is too large for interactive use. Keep total element count under 100,000 for reasonable solve times.
- STEP file size: The backend accepts STEP files up to 50 MB. The parsed mesh JSON is limited to 10 MB.
Preserves
What is the difference between a fixed preserve and a boundary condition?
Both apply zero-displacement constraints, but they work differently:
- Fixed preserve (part-based): Constrains a rectangular or imported geometry region. Placed at specific locations like bolt holes or mounting pads.
- Fixed boundary: Constrains entire edges (2D) or faces (3D) of the design domain. Used for clamped edges or fully bonded surfaces.
Use part-based fixed preserves for localized constraints and boundary conditions for domain-edge constraints.
Can I have multiple output preserves?
Yes. Create multiple output preserves and link each to the input through separate preserve pairs. The solver optimizes the design to satisfy all input-output couplings simultaneously. This is useful for mechanisms with multiple output motions.
What does "preserve" mean in deFlex?
A preserve is a region of the design domain that is protected from material removal during optimization. The solver keeps these areas solid. Preserves also carry boundary conditions (forces, displacements, fixation) that define the optimization problem.
Solver
How long does a typical optimization take?
It depends on the mesh resolution:
| Grid size | Approx. time (60 iterations) |
|---|---|
| 25 x 25 | A few seconds |
| 50 x 50 | Under 1 minute |
| 100 x 100 | 2--5 minutes |
| 200 x 200 | 10--30 minutes |
3D analyses take significantly longer due to the cubic growth in element count.
How does deFlex generate designs?
deFlex uses an AI-driven design optimization engine. The solver intelligently explores the design space, determining where to place material and where to leave void to achieve the best performance for your mechanism. The process is iterative -- with each step, the design becomes more refined and clearly defined. The default Penalization of 3 provides a good balance between convergence speed and design sharpness.
What is the difference between Robust and Nuanced formulation modes?
- Nuanced: Allows per-pair tuning of mechanical advantage (J*) and stiffness (K_p_max). Best when you need fine-grained control over the displacement-force trade-off for each output.
- Robust (2001): A simplified formulation that does not use K_p_max. Tends to be more stable for challenging problems and is a good fallback when Nuanced mode has trouble converging.
Start with the default formulation. Switch to the other if you encounter convergence issues.
Can I cancel a running solver job?
Yes. You can cancel a running solver job from the solver run card in the sidebar. The cancel action stops the backend solver worker and marks the run as cancelled. Any iterations completed before cancellation are preserved and remain viewable.
What happens if I change settings during a run?
Changes to preserves or analysis settings during an active solver run do not affect the running job. The solver uses the settings that were active when you clicked Run. Your changes will apply to the next run.
Accounts and sharing
Can I share a scene with someone who does not have an account?
No. Recipients need a deFlex account to view shared scenes. Sharing generates a link that requires authentication.
Is there a free tier?
Refer to the Pricing page on the deFlex website for current plan details and usage limits.
Can I export the optimized design as a CAD file?
Yes. deFlex supports exporting optimized designs as STL (for 3D printing or structural analysis) and STEP (for direct import into parametric CAD tools like SolidWorks or Fusion 360). See Export Results for details.
Troubleshooting
The viewport is blank or the 3D scene does not render.
- WebGL support: deFlex requires WebGL 2.0. Verify your browser supports it at get.webgl.org.
- Hardware acceleration: Ensure hardware acceleration is enabled in your browser settings.
- Browser extensions: Some ad blockers or privacy extensions can interfere with WebGL. Try disabling extensions temporarily.
- Refresh: A simple page refresh often resolves rendering glitches.
I accidentally deleted a preserve. Can I undo?
deFlex supports undo for most actions. Press Ctrl+Z (or Cmd+Z on macOS) to undo the deletion. If you have already closed the page, the deletion is persisted and cannot be undone.
The solver produces a different result every time I run it.
Small variations between runs are normal. The overall design should be qualitatively similar. If results are dramatically different, the problem may have multiple valid solutions -- this is common for problems with high symmetry or low volume fractions. Try enabling mirror symmetry or adjusting parameters to guide the solver toward a consistent result.