I. Introduction
Hidden mode hybrid systems (HMHSs) are a special class of hybrid automata [29], [39], in which the mode is unknown and mode transitions are driven only by disturbance events. There are a large number of applications that can be well described by hybrid automata models, in which it is not realistic to assume knowledge of the mode. This is the case, for example, of intent-based conflict detection and avoidance for aircraft, in which the intent of aircraft in the environment is unknown and needs to be estimated (see [45] and the references therein). In robotic games such as RoboFlag [11], [16], the intents of non-team members are unknown and need to be identified to allow decisions toward keeping the home zone safe. Next generation warning and active safety systems for vehicle collision avoidance will have to guarantee safety in the presence of human drivers and pedestrians, whose intentions are unknown [1]. More generally, in a variety of multi-agent systems, for example assistive robotics, computer games, and robot–human interaction, the intentions of an observed agent are unknown and need to be identified for control [21].