Mini-Project 3: A CAD-to-Render Robot Reveal

A robot reveal doesn’t have to wait for a finished robot. Top teams such as FRC 1690 (Orbit) pair polished reveals with ‘Behind the Bumpers’-style explainer content. You can do the same with free tools.

Step 1 — Export from Onshape. Onshape is free for FRC and FTC teams. Its export formats include STEP, IGES, STL, and OBJ (plus DWG/DXF/PDF for drawings). For Blender, the two practical paths are:

• Right-click the assembly > Export > STEP (preserves separate parts; import with a Blender STEP add-on, or via FreeCAD as an intermediate). This keeps parts as separate objects so you can assign different materials.
• Or export OBJ for a direct Blender import (Blender imports OBJ natively), accepting that the assembly may come in as one merged mesh. Note that FBX is not a native Onshape export format, so use OBJ or STEP rather than reaching for FBX.

Export at a reasonable tessellation (fine, but not maximum — a 200MB mesh will choke Blender). STL flattens the whole assembly into one mesh and loses per-part grouping, so prefer STEP when you want to color the chassis differently from the intake.

Step 2 — Set the scene in Blender (free). Import the model, then:

• Add a large plane as the floor and a world HDRI or a simple 3-point light setup (a bright key light, a softer fill, a rim light to separate the robot from the background).
• Assign materials: a brushed-metal shader for aluminum, your team’s brand color as a glossy paint on bumpers/branded panels, and dark plastic for wheels.
• Use the Cycles renderer for realism (slower) or Eevee for fast, near-real-time previews.

Step 3 — Animate two money shots.

1. Turntable spin: select the robot, add a Rotation keyframe at frame 1 (0 degrees) and frame 120 (360 degrees), set interpolation to Linear. Instant 4-second 360.
2. Exploded-to-assembled: move each subsystem outward along an axis at frame 1 and back to its real position at frame 60. This ‘explode’ reads as a complex mechanism explained in seconds — exactly why marketing teams love exploded views.

Step 4 — Render and assemble. Render each shot to a PNG image sequence (more crash-resistant than rendering straight to video). Drop the sequences into DaVinci Resolve, layer your music and a title, and intercut with any real shop footage you have.

Step 5 — Publish and share the CAD. Post the reveal, then consider publishing your Onshape CAD link publicly — Orbit, for example, posts its annual robot CAD on Chief Delphi. Sharing CAD is a respected FIRST community contribution and good evidence for your Impact Award narrative.

Reality check: Rendering is time-hungry. Keep the reveal short (15-30 seconds), render overnight if needed, and reuse the .blend scene every season — only the imported robot changes.

Key takeaways

• Export Onshape assemblies as STEP to keep parts separate for per-part materials; OBJ is simpler but may merge meshes (FBX is not an Onshape export option).
• A turntable spin plus an exploded-to-assembled animation are the two highest-value reveal shots.
• Render to PNG image sequences (crash-safe), then assemble with music and titles in DaVinci Resolve.
• Publishing your Onshape CAD publicly doubles as community contribution and Impact Award evidence.

This lesson was adapted from learnfrc.com.