10 Insect Walking: From Reduced Preparations to Natural Terrain

Abstract

Insects are among the most agile animals on the face of the earth. As anyone who has tried to catch one can attest, cockroaches are fast and highly maneuverable. On the other hand, stick insects move slowly through branches, maintaining cryptic camouflage while feeding on the plant’s leaves. The adaptive nature of their walking systems has certainly contributed to their success. Moreover, their capacity to move through many different types of terrains has not been lost on engineers seeking walking models for legged robots. Despite the fact that insects evolved legged locomotion independent of vertebrates, these two groups of animals share many control and mechanical principles, suggesting that they have converged upon excellent solutions to the physical problems that face walking animals (Pearson and Ramirez 1992; Ritzmann et al. 2004; Büschges 2005).

Researchers have made excellent progress in recent years describing insect walking and the neural circuits that control these movements. Much of this progress stems from complementary studies in neurobiology, biomechanics, and modeling. Although much of this work focuses on the basic movement patterns that insects use to walk on flat horizontal surfaces, more recent studies have begun to examine some of the more complex tasks of walking up walls and over ceilings (Duch and Pflüger 1995; Larsen et al. 1995) as well as actions that alter straight ahead movements enabling insects to climb over, tunnel under, or walk around barriers to forward progress as they move toward targets such as food or mates or away from threats. In...