Abstract: The wet grip of tire has always been the focus because it is related to the personal safety of passengers directly. Many methods were employed to improve the wet grip of tire. Researchers paid more attention on bionics method recent years. In nature, tree frogs have high adhesion ability in wet environment, which is mainly due to their footpads having fine polygon grooves (mainly hexagon grooves). To improve the performance of wet grip of tire, from the perspective of bionics, inspired by the footpad of tree frog, the bionic hexagon tread pattern was designed. The friction test was carried out to compare with the common tread patterns such as serrated, striped and square patterns. The results showed that the bionic hexagon tread pattern generally had high friction coefficient and directional stability of friction. The main reason was that the hexagon tread block was less affected by the friction-induced torque and the groove of bionic hexagon tread pattern had better drainage characteristic. The bionic hexagon tread pattern provides new idea and method for the design of tires with high wet grip.

Key words: Tread pattern , · Wet grip , · Bionic , · Foot pad of tree frog , · Adhesion , · Wet friction