• bioinspired robotics
• legged locomotion
• underwater robotics

Bioinspired legged locomotion is attractive for underwater applications that involve moving in unstructured environments. Discrete contact points can be selected by properly controlling the legs, while dexterous mobility can be granted by harnessing the interaction between the body of the robot and the water. Nowadays, the vast majority of underwater legged vehicles employ static locomotion, i.e. the center of mass falls in the polygon of support, while outside water there is a transition toward dynamic locomotion, i.e. the system is statically unstable but dynamically stable thanks to the proper selection of design and control parameters.
The starting point for this work of thesis is a dynamic locomotion model called Underwater Single Loaded Inverted Pendulum (USLIP), which reflects the dynamics of a point-mass supported by a linear compliant leg in a damping environment. The goal of this work is to reproduce USLIP dynamics in a hexapedal robot having segmented legs and serial elastic actuation.
First, the modeling of the single segmented leg has been developed and a deep analysis of the parameter influencing the behavior of the system has been carried out through simulations. Then the single leg model has been used as virtualization of the behavior of group of legs acting synchronously in order to derive a simple control strategy for the behavior of the multilegged robot dynamics. Eventually, experimental data have been collected and analyzed to validate the approach.