Fig. 3. (A)Experimental setup for recording friction, adhesion and contact area of insect adhesive pads. The pad is brought into contact with a glass cover slip attached to a 2-D strain gauge force transducer. The transducer is moved by a 3-D motorised positioning stage. Force signals are amplified and recorded on a computer. A feedback mechanism allows a constant normal force to be maintained. Contact area is recorded using a stereo microscope with coaxial illumination. (B) G. viridula pad contact area. Arrow shows distal direction. (C)Threshold image providing a measure of the real contact area. The red frame shows the estimate of projected pad area. Scale bar=100 µm.