BIOMIMETIC TRANSFER OF PLANT ROOTS FOR PLANETARYANCHORING

The task of autonomously anchoring spacecraft on the surface of any celestial body is extremely challenging. Weight restrictions do not allow for massive design; lacking external control calls for compliant drilling behavior. In search for a new concept we investigated biological mechanisms of ground anchoring. Plants are the first organisms to settle in any type of empty habitat. The roots play an important role during settling providing scalable anchoring. This feature is a consequence of longitudinal growth processes at the tip of the roots (apices) and radial growth on the overall root allowing them to increase in size and strength as well as adapting to changes in external loads. The growth direction of the apex is controlled by a simple set of mechanical and chemical sensors in the transition zone. Root apices also exchange information between each other for coordination. We transfered the technical features of roots concerning anchoring strategy, actuation, and control aspects into engineered concepts. Extending the ’root’ at the tip reduces friction with the substrate, a new type of osmotic actuation works without few moving parts and consumes low energy. A distributed control architecture allows for individual and intra-individual steering, negotiating obstacles and ensuring tight anchoring. Finally we present a technical root integrating the current technological possible solutions.