High-priority processing path Motivation. Often a robot has to fullfill several activities at the same time. For example following a path and avoiding obstacles. While path following is a permanent activity, obstacle avoidance is trigged by the environment and should be immediately reacted upon. Therefore one would like to specify priorities to activities. This is depicted in Figure 8: Figure 8: Managing high priority path with sequential order. Assuming a simplified control loop with the activities sense-plan-act, the obstacle avoidance, which might temporarily stop the robot, should be processed before the planning phase. In this example we assume that these activites are processed in one thread. Derived requirements: - sequential processing of callbacks
