Robot apparatus and method of controlling the same, and computer program

In a robot apparatus having a base unit, a wheel unit of an opposed-two-wheel type mounted on the base unit and having driving wheels drivable so as to face each other, and an upper-body unit provided on an upper portion of the base unit and configured by concatenating one or more joints; a robot apparatus includes an opposed-two-wheel equivalent model, a robot-state observing unit, a control unit performing a control arithmetic operation for the opposed-two-wheel equivalent model, a transforming unit transforming a part of control target values calculated by the control unit to a control target value for the wheel unit, and a joint control unit controlling a joint-driving actuator of the wheel unit and also controlling a joint-driving actuator other than the joint-driving actuator.