Care-O-bot® 3 has an omnidirectional platform, with four steered and driven wheels. This kinematic system enables the robot to move in any desired direction and therefore also safely to negotiate narrow passages. In doing so, Care-O-bot® 3 is also able to autonomously plan and follow an optimal, collision free path to a given target. Dynamic obstacles such as persons are detected by sensors and avoided automatically.
Care-O-bot® 3 is equipped with a highly flexible, commercial arm with seven degrees of freedom as well as with a three-finger hand. This makes it capable of gripping and operating a large number of different everyday objects. Using tactile sensors in the fingers, Care-O-bot® 3 is able to adjust the grasping force.
In order to grasp an object, Care-O-bot® 3 approaches tables or cupboards with its backside. The arm is long enough to grasp objects even from the floor or to reach high shelves. The seventh degree of freedom allows the robot to reach around obstacles. In addition, the arm is used to position objects on the tray.
By synchronizing arm and platform movements, Care-O-bot® 3 is additionally able to autonomously open doors that block its way to the target.
A multiplicity of sensors enables Care-O-bot® 3 to detect the environment in which it is operating. These range from stereo vision colour cameras and laser scanners to a 3D depth-image camera. The sensors serve, for example, to detect and locate relevant environment structures, objects for manipulation as well as obstacles in the robot's environment. Care-O-bot® 3 is additionally capable of learning new objects independently. Its 3D sensors enable it to monitor manipulation operations in real-time, thereby enhancing the safety and dependability of the manipulation process.
The primary interface between Care-O-bot® 3 and the user consists of a tray attached to the front of the robot, which carries objects for exchange between the human and the robot. The tray includes a touch screen and retracts automatically when not in use.
The robot arm is only used to place objects on the tray or take them away from it. It is stopped immediately as soon as people are detected in the vicinity of the robot. Combined with safety sensors for navigation this concept enables the safe operation of Care-O-bot® 3 in public spaces.
The novel design of Care-O-bot® 3 represents an intentional move away from existing humanoid service robots. Instead, the design of the robot has been adapted to its role as an interactive butler, which supports the human user in understanding the capabilities of the robot. Using flexible materials and composites, a soft and pliant form has been created for the cover of the robot. The cover adjusts to accommodate the movements of the upper body and avoids any pinch and shear points. Body gestures like bowing or nodding are e.g. applied to give an intuitive feedback to the user.
The robot has an approximately quadratic footprintwith a length of around 600 mm. The overall height of the robot is around 1450 mm.