Computationally inexpensive egomotion determination for a mobile robot using an active camera

The authors present two computationally inexpensive methods that rapidly and robustly determine both the translational and the rotational components of robot motion through the use of an active camera. Two cases are considered: the first where the instantaneous direction of motion is known, and the second when the instantaneous direction of motion is unknown. Based on the animate vision paradigm, gaze control is used to allow the robot´s camera to fix on items on the environment, and then rapidly move on to other fixation points. The algorithms iteratively seek out fixation points that lie in the forward direction, converging so that the active camera is aligned along the translational direction of motion. At that point, the tracking motion of the camera is equal but opposite in sign to the robot´s rotational component of motion. Experiments were carried out both in simulation and in the real world, giving results that are close to the actual motion parameters of the robot