Mechanical Design of a New Compound Planetary Gearbox Mounted on an Unmanned Ground Vehicle for Off-Road Applications

Gearboxes for motion and torque transmission are fundamental to achieving proper vehicle dynamics. This work proposes the development of a new type of compound planetary gearbox featuring an idler between the planetary gear and the crown wheel. The configuration developed stems from the need to create a gearbox that is compact yet capable of withstanding the stresses it is subjected to. The logical path to developing this new design is presented, starting with the classic configuration and highlighting the limitations encountered during the process. The system structure and kinematic relationships are described, with particular attention to the choice of the number of teeth, meshing conditions, and structural strength. The proposed solution is designed for integration into Unmanned Autonomous Vehicles (UGVs) operating in off-road environments, where high reliability, robustness, and high transmitted torque are required. The proposed design is adaptable to a wide range of mechanical systems, making this work a useful reference tool for the design of compact planetary gearboxes.