CODESYS - CODESYS - the IEC 61131-3 programming system.
LibreCAD - An open source 2D CAD application for Windows, Apple and Linux.
RobotStudio - RobotStudio increase the profitability of your robot system by letting you perform tasks such as training, programming, and optimization
FreeCAD - An open-source parametric 3D modeler
Automgen - Web site for the IRAI products Site Web pour les produits IRAI automation simulation,virtual commissioning,plc programming,pneumatic simulation
SketchUp - 3D for Everyone