Alternative file options other than STL for block/delta stages?

Hi!!

I’m currently using the openflexure delta stage as a starting point in my thesis but I want to improve on the design to fit my needs and I want to better understand how the mechanism works! I was wondering if there was any other CAD files other than the STL files given like a ipt file or maybe a f3d files as I am using Fusion 360 for most of my CAD projects?

Thank you in advance!
Gran

Hi @GBarua, the design files only exist as openSCAD or as the generated STLs. This is discussed in the thread Step Editable CAD.

In a large and open project we need a way to make the source code open and also to track and approve changes in an open way. Version control is very easy for any text-based file format, which is the major advantage of openSCAD. We can easily keep everything open and manage changes using open source methods. Once we have chosen openSCAD for those reasons, it builds our structures using a constructive solid geometry representation. This is fundamentally different from a boundary representation used by many other CAD programs. This unfortunately means that conversion between SCAD format and other file formats is not possible in general. There are some work-arounds that can work for some parts as in the thread Towards STEP components, but this is quite manual and a one-way conversion.

The full design files for the delta stage are at https://gitlab.com/openflexure/openflexure-delta-stage and the files for the block stage are at https://gitlab.com/openflexure/openflexure-block-stage.

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As for better understanding how the mechanism works. I recommend reading some of the papers.

I would recommend installing OpenSCAD and having a bit of a play. Even if you don’t modify the models in there. You may be able to “comment-out” (i.e. remove) some of the external walls to better see the mechanism. Depending on how comfortable with coding you are, you may be able to make all changes in OpenSCAD. If not you may be able to strip the design back to the mechanism, export that STL, for import into your CAD program of choice.

I do recommend printing the main bodies of all 3 designs. Rather than assembling them, use your thumbs to press the bottom of the actuator columns. This will allow you to control the mechanism and get a feel for how it is moving.

When I first joined the OpenFlexure project, the block stage had already been designed. With all its workings being so internal, I found it much harder to understand what was happening than with the microscope. I actually found that taking a printed delta stage and using a saw to cut the side walls off was really helpful.

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Thank you for both for your advice!! Ill look into them immediately especially looking into playing with OpenSCAD!!