Before revision:  In this framework , the general nominal behavior is specified offline through BTs . A new type of leaf node, the prior node, is introduced to specify the desired state to be achieved rather than an action to be executed as in classical BTs.
After revision:  In this framework , the general nominal behavior is specified offline through BTs , where a new type of leaf node, the prior node, is introduced to specify the desired state to be achieved rather than an action to be executed as in classical BTs.