SketchUp is a 3D modelling program for a broad range of applications such as architectural, civil, mechanical, film as well as video game design — and available in free as well as 'professional' versions.
While Sketchup is not open source - meaning - one cannot simply take the source code and make improvements or add features as needed - it is free and widely accessible around the world. The wide accessibility allows wide-scale collaboration to happen. The problem that OSE had in the past with respect to open collaboration on CAD - was that if a user created a design in a certain CAD package, most other collaborators were not able to open it because they did not have access to the same software. This problem ran deep - because even if people did have the same software, and it was created on an older or newer version of the program - the CAD file would still not open properly.
The most common issues regarding widenspread collaboration on CAD that OSE faces are:
- Lack of Software - A collaborator does not have software to open or view a file
- Cross-Platform Compatibility Issues - CAD Software does not exist on all platforms
- Backwards Compatibility Issues - CAD file does not work with older versions of same software
One route to addressing this is using Sketchup. While not open source, it is easy to use and it is widely accessible. The solution path for OSE is to create an open source equivalent to Sketchup.
Even though Sketchup is less powerful than fully-featured CAD programs, OSE claims that it is more important to have wide access be the main selection criterion for the CAD software choice - because that allows development to happen faster. We have seen this in practice: many collaborators working piecemeal on Sketchup create design faster than a single dedicated designer on a professional package. For example, it is easier for 10 people to create fabrication drawings via Sketchup than for 1 person to use a professional CAD package which has a dedicated Fab Drawings generator. Further, recent research by DARPA on collaborative CAD work has shown that N designers can generate a design in a time less than 1/N the time it would take for a single designer to generate the same design. There is empirical evidence that collaborative design takes less cumulative time than one-person design.
Therefore, it is encouraged that any OSE collaborator becomes familiar with Sketchup. Our team will share designs via Sketchup as much as possible. Basic literacy in Sketchup - in terms of being able to open and navigate designs at the very least - is required to be an effective member of the OSE development team. Most of the existing 3D designs of OSE - such as Ironworker Machine, tractor, brick press, pulverizer, Power Cube, house designs, brick rollers - are available in Sketchup.
This does not preclude the use of other packages, such as FreeCAD, and many designs for OSE have been done in FreeCAD already. The choice of the preferred OSE CAD package may change as the open source CAD solution landscape changes with time. Sketchup is the generally-used common platform of OSE in the meantime.
FreeCAD is another option, but FreeCAD currently does not allow for the creation of assemblies or fabrication drawings. FreeCAD has a more difficult to use interface. Sketchup boasts the ability to create simple shapes, extrude them, and modify corners, adges, and faces. OSE is currently considering collaboration with Sunglass.io to develop an open source equivalent to sketchup. Why not start with FreeCAD? According to Kaustuv Biswas of Sunglass, the software architecture of standard packages such as FreeCAD, Autodesk, Solidworks, and others - comes from a paradigm based in the 1970's - where a powerful and complicated CAD kernel was reqiured. Today, Kaustuv states that we can design a much lighter CAD kernel - and make all the heavy analysis and computation on CAD models happen via add-on modules. Thus, the design of the modern CAD platform can be much more modular and lightweight, and that would be the motivation for creating an open source equivalent of Sketchup from scratch - while building on the same open source modules, as needed, that the more complicated packages use.