Predicting trajectory intersection by another road user

A method for predicting that an object located above a road surface traveled on by a vehicle is going to enter into a trajectory of the vehicle, the method comprising:

• receiving, by one or more processors of one or more computing devices, sensor data identifying a first location of the object in an environment of the vehicle at a first point in time and a second location of the object in the environment at a second point in time;
• determining, by the one or more processors, a three-dimensional (3D) boundary of the trajectory through which the vehicle is expected to travel over a period of time;
• determining, by the one or more processors, a shortest first distance between the 3D boundary and a bounding box representing the object when the object is located at the first location and a shortest second distance between the 3D boundary and the bounding box when the object is located at the second location;
• determining, by the one or more processors, a shortest third distance between the 3D boundary and the bounding box when the object is located at a future location at a future point in time;
• and
• predicting, by the one or more processors, that the object is going to enter into the trajectory at the future point in time based on at least the shortest first distance, the shortest second distance, the shortest third distance, the first point in time and the second point in time.