Multi-touch devices like the iPad have become more and more popular over the last couple of years. Nowadays they are not only used for browsing and sending e-mails, but also as a medium for new fields of applications. One particular thing of multi-touch devices is in need of improvement: It is the lack of haptic feedback, which makes it difficult to set parameters precisely.
Regarding to this problem the project has been developed to provide a variety of physical controllers. These controllers expand the usage of a touch device with a haptic feedback while adjusting parameters. By using magnets, the different controllers can easily be arranged onto the iPad. A modular interface appears, which uses a given device just like the iPad.
The system contains three different parts:

• The physical controllers (button, slider and knob), made out of conductive aluminium to pass on the electrical discharge of the human skin.
• A frame, made out of aluminium and plastic, in which the iPad is inserted. The edge of the frame has embedded magnets, making it possible to position the controller precisely and easily.
• The software, running as an app on the iPad. It organizes the control elements and sends the parameters to the corresponding software, which is controlled by the modular interface.