Computer Aided Design applications have become designers? inevitable tools for expressing and simulating innovative ideas and concepts. However, replacing traditional materials and mock-ups with 3D CAD systems, designers are faced with the intangibility problem, unable to physically interact with test products in early stages of design process. As a touchable and graspable interface based on 3D CAD data, we propose Augmented Foam, which applies Augmented Reality technologies to physical blue foams. Using Augmented Foam, a blue foam mock-up is overlaid with a 3D virtual object, which is rendered with the same CAD model used for mock-up production. We presented a method to correct occlusions of the virtual products by user?s hand. Augmented Foam was tested for a mug design and a cleaning robot design. Designers were able to inspect and evaluate the design alternatives interactively and efficiently.