Analysis and characterization of a robotic probe inspired by the plant root apex

Plant roots represent an amazing source of inspiration for designing and developing dexterous, branching robots capable of efficient soil exploration in various scenarios, from environmental monitoring to space exploration. The natural roots, in fact, have optimally evolved to efficiently penetrate and move into the soil. In this work, starting from the study of the plant roots penetration capabilities, we defined the optimal tip shape and the penetration rate of a robotic root apex, by evaluating the penetration resistance to different types of granular substrates. The results showed that the conical and parabolic tips with a pointed shape, similar to the apex tip of the living roots, are more efficient in terms of penetration resistance. The penetration resistance of the robotic root apex results similar to that observed in natural roots. Moreover, we identified the optimal penetration rate of the root-like robotic system as 40 mm/min.