Almost every design project these days uses CAD in one way or another, and this one is no exception. There are many CAD systems available, and we needed to choose one to standardize on for this project. One of the goals of this project is to bring in participants from the community, and the four-figure price tag for most solid modeling programs is a barrier to entry which we feel would exclude a lot of interested people from customizing and improving on our designs.
This is why we have chosen Alibre Design for the CAD and CAM needs of this project. Alibre has released a free version of their software called Alibre Design Xpress which has enough features to be substantially useful and can open and modify (within limits), files created in the full version of the software. Upgraded features can easily be purchased a la carte and the full versions cost between $1,000 and $1,800, which is quite cheap for a parametric solid modeling program. Alibre Design also allows two users to work on the same model and chat in real time, which can be used for support or collaboration. Greg Milliken, CEO of Alibre, has generously donated several full seats of the software for use in the Open Prosthetics project.