Michael Bennemann, Tobias Seidl, Werner Baumgartner

• Adhesive organs enable insects to reversibly adhere to substrates even during rapid locomotion. In this process a very fast but reliable change of adhesion and detachment is realised. The stick insect Carausius morosus detaches its adhesive organs by peeling them off the substrate, meaning little areas of the adhesive organs are detached one after another. For such a detachment mechanism low pulling forces are needed. A detachment mechanism as peeling seems also for artificial adhesion devices to be the easiest and the most effortless mechanism for detachment. However, artificial adhesion devices mostly exhibit a solid backing layer preventing effortless peeling. To lift up and detach a small area at the corner of an adhesion device the backing layer has to be tilted, resulting in a deformation of the whole adhesion device, which requires high forces. Subdividing the backing layer into small subunits allows a detachment of a small area at the corner of the adhesion device without deforming the rest of the adhesion device. Thereby, less force is needed to initiate and to complete detachment. To realise an easy detachment of artificial adhesion devices we constructed a holder, which gradually detaches an adhesion device from two sides off the substrate. During normal loading the subunits of the holder interlock with each other so that the pulling force is equally distributed over the whole contact area of the adhesion device ensuring maximal adhesion force. In addition, the holder can be used to increase adhesion during application of the adhesion device. When brought into contact with the substrate with lifted sides, which are lowered subsequently, air trapping is prevented and hence the area of contact can be maximised.