Accelerated Product Development with Next Generation CAD Automation

Computer-Aided Design (CAD) has traditionally been dominated by desktop-bound applications, where the geometric kernel, user interface, and data storage are tightly coupled within a local executable. This monolithic architecture has inherent limitations regarding collaboration, version control, and automation.

Onshape distinguishes itself from traditional file-based CAD systems through its cloud-native architecture. This architecture enables unique automation capabilities that range from internal geometry creation (FeatureScript) to enterprise-wide data management (REST API).

FeatureScript: A First-Class Citizen

FeatureScript is a proprietary programming language designed by Onshape to build Custom CAD tools. It is the exact same language used by Onshape developers to create standard features like Extrude, Fillet, and Chamfer.

Key Differences from Traditional Macros

• Deep Integration: Unlike traditional CAD macros, FeatureScript runs inside the geometry engine. It rebuilds robustly when upstream geometry changes.
• First-Class Citizens: Custom features created with FeatureScript appear in the toolbar, have their own dialog boxes, and behave exactly like native Onshape features.
• Context-Aware: Scripts can query the model (e.g., "find all flat faces parallel to the Top plane") to apply operations intelligently.

Onshape Customer Example: Trek

Custom cable routing at Trek. Read the case study.

High-performance bicycle frames feature internal cable routing to reduce drag and protect components. Designing the void spaces (tunnels) for these cables is a nightmare of 3D splines, guide curves, and sweep operations.

In their previous CAD system, routing cables for a full frame was a labor-intensive process taking over a day. Engineers had to manually manage spline handles and constantly check for "kinks" (bends that violate the minimum radius of the cable).

The Automation: Trek developed a proprietary "Cable Routing" feature. The engineer simply selects the start point (e.g., the brake lever), the end point (e.g., the caliper), and a few guide points. The script actively monitors the curvature. If a bend is too tight, it visually flags the error (e.g., highlighting the section in red and prompting "that's too tight"). The engineer can add a guide point to relax the curve, and the geometry updates instantly.

The time to route a full frame dropped from more than 8 hours to less than 30 minutes. This single automation recovered an estimated 20%-30% of the CAD specialists' time, allowing them to focus on frame dynamics rather than spline management.

The Onshape API: External Integration

While FeatureScript handles geometry, the Onshape API handles data. It is a robust REST API that allows external applications to read, write, and modify Onshape documents.

Capabilities

• Data Extraction: Automatically export BOMs (Bill of Materials) to CSV or JSON.
• Mass Translation: Batch convert documents to STEP, PDF, or DXF formats.
• ERP/PLM Connection: Sync Onshape release states with external systems (e.g., NetSuite, SAP).
• Document Management: Create new documents, copy workspaces, or move files between folders programmatically.

Tools for Developers

• Glassworks API Explorer: Onshape's built-in interactive documentation (available here) allows you to test API calls directly in your browser.
• Client Libraries: While you can make raw HTTP requests, the community and partners maintain client libraries. The most popular for Python is onshape-client.
• Keys & OAuth: Scripts can authenticate using simple API Keys (for internal tools) or OAuth2 (for public App Store applications).

Onshape Partner Examples

Onshape REST API enables seamless error-free exchange of CAD Data with any toolset you might need to complete your design workflow.

For example, Onshape partners Luminary Cloud and SimScale have leveraged Onshape’s REST API to build “file-less”, cloud-native integrations that fundamentally change how advanced simulation tools are accessed and simulation data is managed.