Travel assistance method and travel assistance device

A travel assistance method for a vehicle to be executed by a processor, comprising:

• acquiring, from a device for storing map information, information on static traveling path boundaries between a traveling path of a subject vehicle and other than the traveling path;
• acquiring, from a sensor for detecting surrounding environment of the subject vehicle, information on dynamic traveling path boundaries different from the static traveling path boundaries;
• generating, based on the information on the static traveling path boundaries, a static traveling path on which the subject vehicle can travel;
• generating, based on the information on the static traveling path and the dynamic traveling path boundaries, a dynamic traveling path which is shorter than the static traveling path and corresponds to the surrounding environment;
• and
• controlling the subject vehicle to travel along a target traveling path including the static traveling path and the dynamic traveling path,
• wherein a calculation cycle of the processor in a process of generating the static traveling path is longer than a calculation cycle of the processor in a process of generating the dynamic traveling path.