4 wheel transformable Mobile platform

We developed a mobile platform capable of transforming between 4 wheel rapid driving mode with ZMP stabilization and 2 wheel balancing mode. Usually, the 4 wheel mobile platforms have low acceleration due to the high center of mass. Using the model-based ZMP stabilization method, we achieved high acceleration performance with maintaining stable ZMP. We use a LQR controller for two wheel balancing mode. In the 2 wheel balancing mode, there are two different driving modes, self-balancing mode, human-riding mode. The transformation between four wheel and two wheel mode is made possible by swing up and swing down control method.