Scientific Schematics and Diagrams
Overview
Scientific schematics and diagrams transform complex concepts into clear visual representations for publication. This skill uses Nano Banana 2 AI for diagram generation with Gemini 3.6 Flash quality review.
How it works:
- Describe your diagram in natural language
- Nano Banana 2 generates publication-quality images automatically
- Gemini 3.6 Flash reviews quality against document-type thresholds
- Smart iteration: Only regenerates if quality is below threshold
- Publication-ready output in minutes
- No coding, templates, or manual drawing required
Quality Thresholds by Document Type: | Document Type | Threshold | Description | |---------------|-----------|-------------| | journal | 8.5/10 | Nature, Science, peer-reviewed journals | | conference | 8.0/10 | Conference papers | | thesis | 8.0/10 | Dissertations, theses | | grant | 8.0/10 | Grant proposals | | preprint | 7.5/10 | arXiv, bioRxiv, etc. | | report | 7.5/10 | Technical reports | | poster | 7.0/10 | Academic posters | | presentation | 6.5/10 | Slides, talks | | default | 7.5/10 | General purpose |
Simply describe what you want, and Nano Banana 2 creates it. All diagrams are stored in the figures/ subfolder and referenced in papers/posters.
Quick Start: Generate Any Diagram
Create any scientific diagram by simply describing it. Nano Banana 2 handles everything automatically with smart iteration:
# Generate for journal paper (highest quality threshold: 8.5/10)
python scripts/generate_schematic.py "CONSORT participant flow diagram with 500 screened, 150 excluded, 350 randomized" -o figures/consort.png --doc-type journal
# Generate for presentation (lower threshold: 6.5/10 - faster)
python scripts/generate_schematic.py "Transformer encoder-decoder architecture showing multi-head attention" -o figures/transformer.png --doc-type presentation
# Generate for poster (moderate threshold: 7.0/10)
python scripts/generate_schematic.py "MAPK signaling pathway from EGFR to gene transcription" -o figures/mapk_pathway.png --doc-type poster
# Custom max iterations (max 2)
python scripts/generate_schematic.py "Complex circuit diagram with op-amp, resistors, and capacitors" -o figures/circuit.png --iterations 2 --doc-type journal
What happens behind the scenes:
- Generation 1: Nano Banana 2 creates initial image following scientific diagram best practices
- Review 1: Gemini 3.6 Flash evaluates quality against document-type threshold
- Decision: If quality >= threshold → DONE (no more iterations needed!)
- If below threshold: Improved prompt based on critique, regenerate
- Repeat: Until quality meets threshold OR max iterations reached
Smart Iteration Benefits:
- ✅ Saves API calls if first generation is good enough
- ✅ Higher quality standards for journal papers
- ✅ Faster turnaround for presentations/posters
- ✅ Appropriate quality for each use case
Output: Versioned images plus a detailed review log with quality scores, critiques, and early-stop information.
Configuration
Set your OpenRouter API key:
export OPENROUTER_API_KEY='your_api_key_here'
Get an API key at: https://openrouter.ai/keys
AI Generation Best Practices
Effective Prompts for Scientific Diagrams:
✓ Good prompts (specific, detailed):
- "CONSORT flowchart showing participant flow from screening (n=500) through randomization to final analysis"
- "Transformer neural network architecture with encoder stack on left, decoder stack on right, showing multi-head attention and cross-attention connections"
- "Biological signaling cascade: EGFR receptor → RAS → RAF → MEK → ERK → nucleus, with phosphorylation steps labeled"
- "Block diagram of IoT system: sensors → microcontroller → WiFi module → cloud server → mobile app"
✗ Avoid vague prompts:
- "Make a flowchart" (too generic)
- "Neural network" (which type? what components?)
- "Pathway diagram" (which pathway? what molecules?)
Key elements to include:
- Type: Flowchart, architecture diagram, pathway, circuit, etc.
- Components: Specific elements to include
- Flow/Direction: How elements connect (left-to-right, top-to-bottom)
- Labels: Key annotations or text to include
- Style: Any specific visual requirements
Scientific Quality Guidelines (automatically applied):
- Clean white/light background
- High contrast for readability
- Clear, readable labels (minimum 10pt)
- Professional typography (sans-serif fonts)
- Colorblind-friendly colors (Okabe-Ito palette)
- Proper spacing to prevent crowding
- Scale bars, legends, axes where appropriate
When to Use This Skill
This skill should be used when:
- Creating neural network architecture diagrams (Transformers, CNNs, RNNs, etc.)
- Illustrating system architectures and data flow diagrams
- Drawing methodology flowcharts for study design (CONSORT, PRISMA)
- Visualizing algorithm workflows and processing pipelines
- Creating circuit diagrams and electrical schematics
- Depicting biological pathways and molecular interactions
- Generating network topologies and hierarchical structures
- Illustrating conceptual frameworks and theoretical models
- Designing block diagrams for technical papers
How to Use This Skill
Simply describe your diagram in natural language. Nano Banana 2 generates it automatically:
python scripts/generate_schematic.py "your diagram description" -o output.png
That's it! The AI handles:
- ✓ Layout and composition
- ✓ Labels and annotations
- ✓ Colors and styling
- ✓ Quality review and refinement
- ✓ Publication-ready output
Works for all diagram types:
- Flowcharts (CONSORT, PRISMA, etc.)
- Neural network architectures
- Biological pathways
- Circuit diagrams
- System architectures
- Block diagrams
- Any scientific visualization
No coding, no templates, no manual drawing required.
AI Generation Mode (Nano Banana 2 + Gemini 3.6 Flash Review)
Smart Iterative Refinement, Advanced Usage, and Examples
The generate-review-refine loop, the Python API and command-line options, prompt engineering guidance, and four worked examples (CONSORT flowchart, neural network architecture, biological pathway, system architecture) are in references/iterative_refinement.md.
The loop stops as soon as the review passes, so a simple diagram usually costs one iteration; only complex figures use the full budget.
Command-Line Usage
The main entry point for generating scientific schematics:
# Basic usage
python scripts/generate_schematic.py "diagram description" -o output.png
# Custom iterations (max 2)
python scripts/generate_schematic.py "complex diagram" -o diagram.png --iterations 2
# Verbose mode
python scripts/generate_schematic.py "diagram" -o out.png -v
Note: The Nano Banana 2 AI generation system includes automatic quality review in its iterative refinement process. Each iteration is evaluated for scientific accuracy, clarity, and accessibility.
Best Practices Summary
Design Principles
- Clarity over complexity - Simplify, remove unnecessary elements
- Consistent styling - Use templates and style files
- Colorblind accessibility - Use Okabe-Ito palette, redundant encoding
- Appropriate typography - Sans-serif fonts, minimum 7-8 pt
- Vector format - Always use PDF/SVG for publication
Technical Requirements
- Resolution - Vector preferred, or 300+ DPI for raster
- File format - PDF for LaTeX, SVG for web, PNG as fallback
- Color space - RGB for digital, CMYK for print (convert if needed)
- Line weights - Minimum 0.5 pt, typical 1-2 pt
- Text size - 7-8 pt minimum at final size
Integration Guidelines
- Include in LaTeX - Use
\includegraphics{}for generated images - Caption thoroughly - Describe all elements and abbreviations
- Reference in text - Explain diagram in narrative flow
- Maintain consistency - Same style across all figures in paper
- Version control - Keep prompts and generated images in repository
Troubleshooting Common Issues
AI Generation Issues
Problem: Overlapping text or elements
- Solution: AI generation automatically handles spacing
- Solution: Increase iterations:
--iterations 2for better refinement
Problem: Elements not connecting properly
- Solution: Make your prompt more specific about connections and layout
- Solution: Increase iterations for better refinement
Image Quality Issues
Problem: Export quality poor
- Solution: AI generation produces high-quality images automatically
- Solution: Increase iterations for better results:
--iterations 2
Problem: Elements overlap after generation
- Solution: AI generation automatically handles spacing
- Solution: Increase iterations:
--iterations 2for better refinement - Solution: Make your prompt more specific about layout and spacing requirements
Quality Check Issues
Problem: False positive overlap detection
- Solution: Adjust threshold:
detect_overlaps(image_path, threshold=0.98) - Solution: Manually review flagged regions in visual report
Problem: Generated image quality is low
- Solution: AI generation produces high-quality images by default
- Solution: Increase iterations for better results:
--iterations 2
Problem: Colorblind simulation shows poor contrast
- Solution: Switch to Okabe-Ito palette explicitly in code
- Solution: Add redundant encoding (shapes, patterns, line styles)
- Solution: Increase color saturation and lightness differences
Problem: High-severity overlaps detected
- Solution: Review overlap_report.json for exact positions
- Solution: Increase spacing in those specific regions
- Solution: Re-run with adjusted parameters and verify again
Problem: Visual report generation fails
- Solution: Check Pillow and matplotlib installations
- Solution: Ensure image file is readable:
Image.open(path).verify() - Solution: Check sufficient disk space for report generation
Accessibility Problems
Problem: Colors indistinguishable in grayscale
- Solution: Run accessibility checker:
verify_accessibility(image_path) - Solution: Add patterns, shapes, or line styles for redundancy
- Solution: Increase contrast between adjacent elements
Problem: Text too small when printed
- Solution: Run resolution validator:
validate_resolution(image_path) - Solution: Design at final size, use minimum 7-8 pt fonts
- Solution: Check physical dimensions in resolution report
Problem: Accessibility checks consistently fail
- Solution: Review accessibility_report.json for specific failures
- Solution: Increase color contrast by at least 20%
- Solution: Test with actual grayscale conversion before finalizing
Resources and References
Detailed References
Load these files for comprehensive information on specific topics:
references/best_practices.md- Publication standards and accessibility guidelines
External Resources
Python Libraries
- Schemdraw Documentation: https://schemdraw.readthedocs.io/
- NetworkX Documentation: https://networkx.org/documentation/
- Matplotlib Documentation: https://matplotlib.org/
Publication Standards
- Nature Figure Guidelines: https://www.nature.com/nature/for-authors/final-submission
- Science Figure Guidelines: https://www.science.org/content/page/instructions-preparing-initial-manuscript
- CONSORT Diagram: http://www.consort-statement.org/consort-statement/flow-diagram
Integration with Other Skills
This skill works synergistically with:
- Scientific Writing - Diagrams follow figure best practices
- Scientific Visualization - Shares color palettes and styling
- LaTeX Posters - Generate diagrams for poster presentations
- Research Grants - Methodology diagrams for proposals
- Peer Review - Evaluate diagram clarity and accessibility
Quick Reference Checklist
Before submitting diagrams, verify:
Visual Quality
- [ ] High-quality image format (PNG from AI generation)
- [ ] No overlapping elements (AI handles automatically)
- [ ] Adequate spacing between all components (AI optimizes)
- [ ] Clean, professional alignment
- [ ] All arrows connect properly to intended targets
Accessibility
- [ ] Colorblind-safe palette (Okabe-Ito) used
- [ ] Works in grayscale (tested with accessibility checker)
- [ ] Sufficient contrast between elements (verified)
- [ ] Redundant encoding where appropriate (shapes + colors)
- [ ] Colorblind simulation passes all checks
Typography and Readability
- [ ] Text minimum 7-8 pt at final size
- [ ] All elements labeled clearly and completely
- [ ] Consistent font family and sizing
- [ ] No text overlaps or cutoffs
- [ ] Units included where applicable
Publication Standards
- [ ] Consistent styling with other figures in manuscript
- [ ] Comprehensive caption written with all abbreviations defined
- [ ] Referenced appropriately in manuscript text
- [ ] Meets journal-specific dimension requirements
- [ ] Exported in required format for journal (PDF/EPS/TIFF)
Quality Verification (Required)
- [ ] Ran
run_quality_checks()and achieved PASS status - [ ] Reviewed overlap detection report (zero high-severity overlaps)
- [ ] Passed accessibility verification (grayscale and colorblind)
- [ ] Resolution validated at target DPI (300+ for print)
- [ ] Visual quality report generated and reviewed
- [ ] All quality reports saved with figure files
Documentation and Version Control
- [ ] Source files (.tex, .py) saved for future revision
- [ ] Quality reports archived in
quality_reports/directory - [ ] Configuration parameters documented (colors, spacing, sizes)
- [ ] Git commit includes source, output, and quality reports
- [ ] README or comments explain how to regenerate figure
Final Integration Check
- [ ] Figure displays correctly in compiled manuscript
- [ ] Cross-references work (
\ref{}points to correct figure) - [ ] Figure number matches text citations
- [ ] Caption appears on correct page relative to figure
- [ ] No compilation warnings or errors related to figure
Environment Setup
# Required
export OPENROUTER_API_KEY='your_api_key_here'
# Get key at: https://openrouter.ai/keys
Getting Started
Simplest possible usage:
python scripts/generate_schematic.py "your diagram description" -o output.png
Use this skill to create clear, accessible, publication-quality diagrams that effectively communicate complex scientific concepts. The AI-powered workflow with iterative refinement ensures diagrams meet professional standards.