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CAD Model Import Guide

fll-sim supports importing custom robot designs created in BrickLink Studio (.io) or LeoCAD / LDraw (.ldr, .mpd).

BrickLink Studio is the most popular CAD tool used by FIRST LEGO League teams. Studio saves files in the .io format, which is an unencrypted ZIP archive containing: * model.ldr: The LDraw-formatted structural part hierarchy * thumbnail.png: Rendered thumbnail preview

How to Import

  1. In BrickLink Studio, save your robot model (File \(\to\) Save As... \(\to\) my_robot.io).
  2. Open the FLL Robot Simulator in your browser.
  3. In the top navigation bar, click đź“‚ Import Studio .io / .ldr.
  4. Select your .io file.
  5. The pre-solver will automatically:
  6. Unpack the model hierarchy
  7. Map part numbers to Technic physical mass and dimensions
  8. Cluster all static beams and pins
  9. Spawn your robot on the virtual competition table!

2. Importing LeoCAD / LDraw (.ldr, .mpd)

If you use LeoCAD or the official LDraw library: 1. Export your model as .ldr (File \(\to\) Export \(\to\) LDraw...). 2. Upload the .ldr file through the đź“‚ Import button.

3. Modeling Best Practices for Simulation

To ensure your CAD model clusters cleanly into the proper kinematic bodies: * Friction Pins vs. Axles: Use standard friction pins (2780, 6558) to connect beams rigidly to the chassis. * Motor Mounting: Ensure motor stators (45601, 45602) are rigidly pinned to the frame. * Wheel Axles: Ensure wheel rims (56145) are connected to motor output shafts with cross-axles. The clustering solver will automatically detect the 1-DOF rotational freedom and configure a revolute joint.

4. Official Season Mission Models & Community Attribution

The official FLL competition mission models available in the simulator (Bioglow, Unearthed, Submerged, Masterpiece, Superpowered) were converted and modeled in BrickLink Studio format by Komurobo.

  • Model Source: Komurobo FLL 3D Models
  • Contact & Project: Komurobo.com (info@komurobo.com)
  • Community Notice: We gratefully credit the independent creators at Komurobo for making these digital assets available to the global robotics education community. Komurobo is an independent initiative not affiliated with FIRST® or Robotique FIRST QuĂ©bec. All LEGO®, Technic™, and SPIKE™ trademarks belong to the LEGO Group, used here for non-commercial educational robotics practice.