Comment by tzs

9 years ago

Are there CAD models available for the various Lego components? I'm wondering if, given such models, you could use rendering software to generate labeled training images. That could allow you to get a large training set with many images for each kind of component in many different orientations, even for components you do not yet have.

If the CAD models are not available, how much work is it to make a CAD model given an instance of a particular component? I'd expect that for some components, such as those NxM plates, you'd only need to build one model by hand in CAD software, and then could algorithmically generate the models for other sizes.

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tzs

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ant6n  9 years ago

I don't know CAD models, but it would probably make sense to scrape the lego website where you can select all their bricks. Each named brick has 8 images (various orientations):

https://shop.lego.com/Pick-a-Brick

I find it hard to believe that there are only 1421 bricks, including color combinations.

Example: "Apple with leaf", Color Family: Dark Green, Exact Color: Bright green, Category: Foodstuff Element ID: 4107050, Design ID: 33051, orientation 8: https://sh-s7-live-s.legocdn.com/is/image/LEGOPCS/4107050_s8

...This also makes me wonder whether it would make sense to set up multiple cameras, to get multiple orientations for every block. Use the image that has the lowest classification error, but use all orientations to train the network.

  • jacquesm  9 years ago

    The Lego pick-a-brick store is very very limited.

    The images are not very useful to me because the images the machine takes are very different from those. But maybe it would somehow contribute. I'd be very ware of using other people's copyrighted content though.

    I do use multiple orientations.

    • ant6n  9 years ago

      Point taken re copyright. Re similarity, it may be possible to write some sort of imagemagic filter that makes the bricks appear more realistic somehow. (But yeah, this would probably only be useful as a starting point for training the very rare bricks)