Using Time-of-Flight Cameras with Active Gaze Control for 3D Collision Avoidance

We propose a 3D obstacle avoidance method for mobile robots. Besides the robot's 2D laser range finder, a Time-of-Flight camera is used to perceive obstacles that are not in the scan plane of the laser range finder. Existing approaches that employ Time-of-Flight cameras suffer from the limited field-of-view of the sensor. To overcome this issue, we mount the camera on the head of our anthropomorphic robot Dynamaid. This allows to change the gaze direction through the robot's pan-tilt neck and its torso yaw joint. The proposed obstacle detection method is robust against kinematic inaccuracies and noise in the range measurements. The gaze controller takes motion blur effects into account and controls the gaze depending on the robot's motion and the obstacles in its vicinity. In experiments, we demonstrate that our approach enables the robot to avoid obstacles that the laser range finder can not perceive. We also compare our active gaze control strategy with a fixed gaze orientation.