It is determined an ADV is inevitable to collide with at least one of the objects surrounding the ADV based on the relative positions and speeds between the ADV and the objects in view of the physical dimensions of the ADV. An object may be another vehicle, a pedestrian, a bicycle, a static obstacle. For each of the objects, a collision cost between the ADV and the object is calculated using a set of one or more cost functions or cost algorithms. A collision cost represents an amount of potential damage if the collision is to occur. One of the objects is selected whose collision cost is the least amongst the objects. A path or trajectory is planned for the ADV leading or towards to the selected object to minimize the potential damage when the ADV potentially collide with the selected object compared to the remaining objects.