Requirements become geometry.
Design, analyze, compare, and document helical, disc, wave, constant-force, and power/clock springs using an auditable local-first engineering model.
Project
Current design
Engineering status
Local Project Library
Multiple projects are stored only in this browser. Archived projects remain recoverable until explicitly deleted.
Demonstration projects
Demo data never loads automatically. Choose one deliberately.
Reference Context
Document how references apply to this design.
Validation Suite
Regression checks for Calculation Model 2.8.
Validation details
Offline & Recovery
Storage health and portable backups.
1. Requirements
Define what the spring must do before selecting geometry.
Mechanical
Envelope
Life & environment
Manufacturing constraints
2. Material
Reference profiles now separate stiffness, static strength, fatigue reference, environmental guidance, and provenance.
Material selection
Custom material profile
Select “Custom material” to activate these project-specific properties.
Material comparison
| Material | G MPa | E MPa | Static ref MPa | Ultimate ref MPa | Endurance ref MPa | Environment |
|---|
3. Geometry
Define the spring body and end geometry. Derived diameters update automatically.
Spring body
Geometry results
Manufacturing context
4. Load Cases
Store the positions that matter in service, test, shipping, and overtravel.
| Name | Position | Force / Torque | Stress | Margin | Fatigue role |
|---|
5. Analysis
Inspect rate, force/torque, stress, static margin, and operating limits.
Performance curve
Calculation inspector
Performance table
6. Fatigue
Evaluate the selected operating range using explicit mean/alternating stress and configurable screening factors.
Fatigue load range
Adjustment factors
Fatigue assessment
Mean / alternating stress diagram
7. Manufacturability
Configurable rule-based review separates analytical constraints, common guidance, shop rules, and supplier-dependent considerations.
Findings
Manufacturing assumptions
Configurable shop/design rules
These thresholds are project rules, not universal manufacturing limits. Preserve supplier capability notes separately.
8. Tolerances
Propagate dimensional variation into rate, output, stress, and physical clearance using deterministic worst-case corners and seeded Monte Carlo simulation.
Key tolerances
Robust-design Monte Carlo
Normal distributions are truncated at the stated dimensional/material limits. Uniform and triangular distributions use the same entered ± limits. Correlation is applied between wire diameter and outside diameter using a Gaussian-copula screen. Statistical yield does not replace deterministic tolerance or qualification requirements.
Rate sensitivity
Project-specific sensitivity is calculated by perturbing each variable and rerunning the rate equation.
Worst-case corner analysis
| Result | Minimum | Nominal | Maximum |
|---|
Monte Carlo distribution
Production yield screen
| Criterion | Pass probability | Failures | Basis |
|---|
Yield is the fraction of the simulated population satisfying the listed analytical constraints. Real production yield also depends on process stability, measurement uncertainty, supplier capability and non-modeled variables.
Process capability
| Characteristic | Mean | σ | LSL | USL | Cp | Cpk |
|---|
Robustness drivers
9. Explore
Explore one- and two-parameter trade spaces, pin promising designs, and solve compression-spring requirements as a constrained search problem.
One-dimensional sweep
The chart shows rate and maximum stress together so geometry-performance tradeoffs are visible rather than reduced to one number.
Sweep results
Two-parameter trade space
Pinned exploration designs
| Name | Wire | OD | Coils | Rate | Stress | Margin |
|---|
Optimization Engine 3.0
Searches wire diameter, mean diameter, active coils, total coils, and free length against the current requirements. It reports why the search is infeasible instead of silently returning an empty table.
Solver evidence
Pareto frontier
Non-dominated candidates across target error, stress, fatigue, mass, package, travel margin, and manufacturability. No weighted score is required to qualify for the frontier.
| # | Rate err | Force err | Stress util. | Fatigue | Mass | OD | Travel margin |
|---|
Minimum requirement relaxation
When the design space is infeasible, this screen estimates the smallest single-constraint relaxation that would admit at least one analytical candidate. It is a decision aid, not permission to change a requirement.
Feasibility map
Wire diameter versus mean coil diameter. Each cell searches active-coil count and shows whether any configuration satisfies the current solver constraints.
Candidate designs
| # | Wire | Mean D | Active coils | Rate | Work force | Stress | Fatigue margin | Solid margin | Mass | Mfg | Score |
|---|
Design comparison
| Name | Type | Wire | OD | Rate | Max stress | Margin | Fatigue |
|---|
9A. Multi-Spring Systems
Combine the current spring with secondary elements in series, parallel, opposing, helper, nested, or staged arrangements.
System configuration
The current design is the primary spring. Added elements are rate/preload/engagement models for system trade studies; their individual stresses must be verified separately.
Equivalent system
Spring elements
| Element | Role | Rate | Preload | Engage | Direction | Load @ work | Share |
|---|
9B. Mechanism Coupling
Translate spring displacement and force into mechanism output motion and force/torque using explicit kinematic screening models.
Coupling definition
These are quasi-static kinematic/energy screening models. Friction, compliance, backlash, contact stress, bearing reactions, structural deflection and dynamic effects require separate verification.
Coupled result
Mechanism evidence
9C. Dynamic Spring Analysis
Screen natural frequency, excitation ratio, damping, dynamic amplification, resonance, spring surge and impact-energy demand for translational and rotational spring systems.
Dynamic inputs
This is a single-degree-of-freedom screening model. Distributed spring modes, nonlinear contact, mechanism compliance, structural modes, damping variation, impact shape and full transient response require separate analysis or test.
Dynamic summary
Resonance / surge screen
Impact screen
Dynamic evidence
10. Drawing
Manufacturer-facing engineering sheet with dimensions, process notes, critical characteristics, and revision identification.
11. Specification
Compact sourcing/RFQ package with geometry, performance, process, inspection, quantity, and supplier-response requirements.
12. Report
Formal design-review package with requirements compliance, calculation evidence, findings, tolerance evidence, and revision comparison.