Mechanism for the Locomotion Layout Reconfiguration of the Agri_q Mobile Robot

This paper deals with the design of a mechanism able to modify the locomotion layout of a novel UGV (Unmanned Ground Vehicle), named Agri_q, specifically designed for precision agriculture applications. Taking into account that it has to move over an irregular and loose soil, the rover is equipped with eight wheels, each couple supported by a rocker, which ensure a wide contact surface between the vehicle and the ground. A limit of this solution is the substantial lateral slithering occurring when the rover engages curved trajectories, which causes an increase of the needed driving torque. Therefore, reducing the number of ground contact points to compare the torque adsorption in different configurations, namely four, six or eight wheels, could be of interest. The designed mechanism has to lift one of the two wheels connected to the rocker providing at the same time a suspension system to reduce the vibrations transmitted to the sub-chassis. Having analyzed the system requirements, two possible functional solutions are proposed and compared. Finally, the synthesis of the chosen mechanism is presented.