Automating Engineering Reports with Client-Side PDF Generation

The Problem with Manual Reports

Engineering calculation reports follow a predictable structure: project header, design parameters, calculation steps, results summary, and code references. Yet most engineers spend significant time formatting these reports manually in Word, copying numbers from spreadsheets, and adjusting page breaks. Every time a design changes, the entire report needs updating. This is exactly the kind of repetitive work that automation eliminates.

Client-Side PDF Libraries

Two JavaScript libraries handle most PDF generation needs:

• jsPDF — lightweight, generates PDFs from scratch with precise control over positioning, fonts, and graphics. Best for structured calculation sheets with tables and diagrams.
• html2pdf.js — wraps html2canvas and jsPDF to convert rendered HTML directly to PDF. Best when you already have a well-styled HTML output and want a quick "Save as PDF" button.

Both run entirely in the browser. No data is sent to any server — an important consideration when working on confidential projects.

Structuring the Report Template

Define your report layout as a JavaScript template with placeholder tokens for dynamic values. A typical engineering calculation sheet includes:

• Company logo and project information header
• Design code references and applicable standards
• Input parameters table with descriptions and units
• Step-by-step calculations with intermediate results
• Final design summary with pass/fail indicators
• Revision history and engineer's signature block

Adding Tables and Diagrams

Use jsPDF's autoTable plugin for formatted tables — it handles column widths, pagination, and alternating row colors automatically. For diagrams, render them to a canvas element first, then embed the canvas image into the PDF. This approach works for cross-section drawings, shear and moment diagrams, and interaction curves.

Professional Formatting Tips

Workflow Integration

Embed the PDF generator into your web calculator tools. After the user completes a design check, a single button click generates the full calculation report. The engineer reviews the PDF, saves it to the project folder, and moves on. What used to take 30 minutes of formatting now takes 3 seconds.

Sample Code

// Generate a structural report PDF with jsPDF
function generateReport(project, results) {
  const doc = new jspdf.jsPDF();

  // Header
  doc.setFontSize(18);
  doc.text('Structural Design Report', 20, 25);
  doc.setFontSize(11);
  doc.text(`Project: ${project.name}`, 20, 35);
  doc.text(`Date: ${new Date().toLocaleDateString()}`, 20, 42);

  // Results table
  let y = 55;
  doc.setFontSize(10);
  results.forEach(r => {
    doc.text(r.member, 20, y);
    doc.text(r.ratio.toFixed(3), 80, y);
    doc.text(r.ratio <= 1.0 ? 'PASS' : 'FAIL', 120, y);
    y += 8;
  });

  doc.save(`${project.name}-report.pdf`);
}

// Usage
generateReport(
  { name: 'Bridge-101' },
  [{ member: 'Beam-B1', ratio: 0.87 }, { member: 'Col-C1', ratio: 0.95 }]
);