Cockroach landing
Cockroaches - however capable of flight they are - are largely ground-dwelling insects and one can assume that flight will always be a non-preferred form of locomotion. Specific adaptations are expected to be present, allowing for optimized landing strategies and transitional phases between aerial descent and terrestrial locomotion. Although the flight apparatus is developed in most representatives, little is known of both flight abilities and aerial performance in cockroaches.
In order to validate the potential arising for future technical applications in unmanned planetary exploration, a first step toward understanding aerial performance in cockroaches was undertaken. Flight experiments were performed on individuals of Blaptica dubia, which were launched from a ramp in 2.5 m height. Three-dimensional video sequences of B. dubia were recorded for whole flight trajectories and additionally starting and landing phases were analysed using high-speed video equipment. Decisional strategies in cockroach flight were mapped as ehtogramms.
Free Flight experiments showed that male specimens of B. dubia are capable of stabilizing their aerial descent by attaining a dorso-ventral righted position and deploying their wings. The descent process mainly consists of 3 distinct phases: a ballistic phase, a body righting and wing deployment phase and a stabilized flight and landing phase. Female B. dubia only display a ballistic fall. The aerial descent in male B. dubia seems to be controlled and directed as in other wingless arthropods as well as vertebrates. As however no highly specialized transitional phases or landing precautions were observed, it remains unclear whether or not cockroaches are appropriate model organisms for a biomimetic approach to landing control in unmanned planetary exploration.