Autonomous travel support device, control method of working vehicle, program, and working vehicle

An autonomous travel support device comprising:

• a sensor configured to sense an environmental state around the working vehicle to provide a sensing result;
• a communication interface configured to communicate, via wired or wireless communication, with a working vehicle, a remote controller, and an external device, the autonomous travel support device being detachably attached to the working vehicle;
• a memory configured to store a program;
• and
• a processor configured to execute the program so as to:
• receive an operation input from a user via the communication interface to cause the working vehicle to travel;
• receive a first switching input as the operation input from the user via the communication interface to operate the working vehicle in a first mode, the first mode manually controlling the travel of the working vehicle by the user via the remote controller held by the user;
• receive a second switching input as the operation input from the user via the communication interface to operate the working vehicle in a second mode, the second mode autonomously controlling the travel of the working vehicle based on an autonomous program and the sensing result;
• determine attenuation of a radio wave in the wireless communication between the working vehicle and the remote controller;
• obtain a distance between the working vehicle and the user holding the remote controller based on the attenuation;
• and
• compare the distance to a predetermined distance,
• wherein the processor is further configured to not permit operation in the second mode by disabling the second switching input when the distance is equal to or less than the predetermined distance, and
• the processor is further configured to keep operating in the first mode or to switch to the first mode when the distance is equal to or less than the predetermined distance.