This study introduces a new design for the drivetrain of a robotic ball. An application for the robotic ball is a rehabilitation device for young children. With these children, movement can be stimulated in a more intuitive way when a robotic ball is used compared to other training programs. Since the ball will be kicked and played with, an important requirement is the ability to handle multiple impacts, i.e. the ball is impact-resistant. Additional requirements are the ability to roll like a normal ball (the center of gravity is in the center of the ball) and maintain low weight and cost. The final design is found through iterative testing and shape optimization of the individual components. The impact resistance of the final design is met by protecting from torque overload and the possibility of absorbing shocks, however, the latter still requires testing to confirm the drivetrain's impact resistance. The proposed design successfully fulfills the size and weight requirements for implementation in a robotic ball, representing a promising step toward creating a robotic ball with enhanced impact resistance. A subject for future research remains the development of the complete robotic ball, with a shell and suspension mechanism.