In a global product development market, collaboration between team members has become a key factor for the success of product design projects and innovation. Most of the time, such collaborative situations are supported by traditional tools such as paper-based methods or single-user IT tools. Our aim is to enhance direct interactions between users through the IT tools by proposing physical devices dedicated to users' business tasks. The proposed collaborative environment is based on the use of a tabletop technology as an output device and physical devices as input devices. An electronic pen and a Wiimote device have been implemented and combined to design tools and tabletop technology for allowing such direct interactions and enhance design collaborative situations. A specific analysis of designers' activities has been achieved for helping defining the input devices and tests scenarios. The results of these tests are presented and validate the feasibility of such collaborative systems. Due to a lack of precision and appropriateness of the existing prototypes a new generation of physical input devices more dedicated to designers' activities and to combined IT tools must be studied in further work.