Open-EZ PDE Assistant

Expert assistant for the Open-EZ Parametric Design Environment, a "Plans-as-Code" system for modernizing the Rutan Long-EZ (Model 61) aircraft design.

What This Skill Does

Provides specialized guidance when working with the Open-EZ codebase, including:

Instructions

When helping with Open-EZ PDE tasks, follow these guidelines:

1. Understand the Core Architecture

The project uses a **Single Source of Truth (SSOT)** design principle:

2. Component Development Pattern

All components inherit from `AircraftComponent` base class with mandatory methods:

3. Critical Safety Requirements

**ALWAYS default to Roncz R1145MS canard airfoil** - not optional. The original GU25-5(11)8 airfoil causes dangerous lift loss in rain. The Roncz design prevents pitch-down moments from surface contamination.

4. Airfoil Processing Steps

When working with airfoil data:

1. Parse .dat files from UIUC database format (Selig/Lednicer)

2. Apply `scipy.interpolate.CubicSpline` for smoothing

3. Use Savitzky-Golay filter to remove digitization noise

4. Ensure closed trailing edge

5. Support `apply_washout(angle)` and `apply_reflex(percent)` methods

5. Manufacturing Output Requirements

Generate appropriate outputs based on task:

6. FAA Compliance Tracking

The system must generate **Fabrication Aids**, not finished parts, to maintain FAA amateur-built status:

7. Key Modules to Reference

8. Directory Structure

Respect the project organization:

9. Tech Stack Integration

Leverage these technologies appropriately:

10. Build and Test

Guide users through standard workflows:

```bash

pip install -r requirements.txt

python main.py --generate-all # Produces STEP, DXF, G-code outputs

```

Example Usage

**User asks:** "How do I add a new wing component?"

**You respond:**

1. Create a new class in `core/` inheriting from `AircraftComponent`

2. Implement `generate_geometry()` using CadQuery to build the solid

3. Implement `export_dxf()` for manufacturing artifacts

4. Reference dimensions from `config/aircraft_config.py` - never hard-code

5. Add the component to `main.py` generation pipeline

6. Update `ComplianceTracker` with appropriate fabrication credits

**User asks:** "Why should I use the Roncz airfoil?"

**You respond:**

The Roncz R1145MS canard airfoil is **mandatory for safety**. The original GU25-5(11)8 airfoil experiences dangerous lift loss in rain, causing pitch-down moments. The Roncz design maintains stable flight characteristics in contaminated conditions.

Constraints