Surface roughness, claw size and leg elasticity influences on the jumping of Acheta domesticus crickets

The jumping of living house crickets (Acheta domesticus) on three sandpapers with different roughness and the mechanical properties of their legs have been studied. The longest jumps are observed when the higher friction occurs, that in turn happens when the average particle diameter of each substratum is comparable to the insect's claw diameter. In the longest jump, the cricket A. domesticus was propelled forwards for almost 30 cm, about 16 times its body length, to a take-off velocity of 1.8 m/s at an angle of 36.9 degrees with a kinetic energy of 520 mu J in agreement with previously published studies where the role of friction was not elucidated. In addition, the crickets' legs were also strained at the constant rate of 1 mm/min, using a tensile testing machine. The observed maximum stress, strain and toughness modulus, defined as the area under the stress-strain curve, are 69.4 MPa, 17.4% and 0.72 MJ/m(3), respectively, and are compatible with the required jumping performances. Finally, we compare the jumping performances of A. domesticus with other jumping insects, such as locusts, planthoppers, froghoppers, bush crickets, pygmy mole crickets, false stick insects and stick insects, which were analysed in previously published papers. (C) 2012 Elsevier Ltd. All rights reserved.