SOLIDWORKS 2018 - Powerful Model Based Definition. Model Based Definition in SOLIDWORKS 2018 is more powerful than ever allowing you to more accurately define all the manufacturing information needed within the 3D model. In SOLIDWORKS 2018 you can now apply datum features to patterns more accurately representing real life designs like the three mounting holes in this cover. Model Based Definition helps companies get products through production faster. MBD in SOLIDWORKS 2018 makes it easy to implement into your Design to Manufacture Process.