In this function category, Swan interacts with static objects. A static object could be a stationary human body. Responses are prompt, gentle, and stable. These functions run in the curvature mode. All of them execute obstacle-avoidanceactions in one of the following two types:
1. The first type is where Swan interacts with an object on its one side, left or right. Hug-Objects, Satellite, and Squash functions deal with this type of motion. Among the three actions, the first two are obstacle-following actions, but the last one is a bouncing-against-obstacle type action.
2. The second type of action is where Swan interacts with two objects on both left and right sides and follows the path between the two side objects. The Gate, Race Track, and Maze functions deal with this type of actions