“freezing robot” problem: once the environment surpasses a certain level of complexity, the planner decides that all forward paths are unsafe, and the robot freezes in place (or performs unnecessary maneuvers) to avoid collisions.
“机器人冻结”问题：一旦环境超过某种复杂度，规划器会认为所有向前的路径是不安全的，机器人“冻结“（plus:或卡住）在原地（或执行不必要的动作（plus:原地瞎晃悠））以避免碰撞。