Target vehicle speed generation method and target vehicle speed generation device for driving assisted vehicle

A target vehicle speed generation method for generating a target vehicle speed of a host vehicle is generated in accordance with a speed limit of a travel path of the host vehicle, the target vehicle speed generation method comprising:

• acquiring the speed limit of the travel path of the host vehicle during travel;
• generating a target acceleration in accordance with the speed limit;
• and
• relaxing a limitation on acceleration during the generating of the target acceleration to a greater extent when the speed limit of the travel path of the host vehicle is high as compared to when the speed limit of the travel path of the host vehicle is low, and
• setting a first acceleration limit value that is increased correspondingly with an increase in the speed limit, setting a second acceleration limit value that is increased correspondingly with an increase in a difference in speed between the speed limit and a host-vehicle speed, and selecting the lower of the first acceleration limit value and the second acceleration limit value as the acceleration limit value.

A target vehicle speed generation method for generating a target vehicle speed of a host vehicle is generated in accordance with a speed limit of a travel path of the host vehicle, the target vehicle speed generation method comprising:

• acquiring the speed limit of the travel path of the host vehicle during travel;
• generating a target acceleration in accordance with the speed limit;
• and
• relaxing a limitation on acceleration during the generating of the target acceleration to a greater extent when the speed limit of the travel path of the host vehicle is high as compared to when the speed limit of the travel path of the host vehicle is low,
• during the acquiring of the speed limit of the travel path of the host vehicle, when it is impossible to acquire the speed limit from road signs or from map data during travel, a speed determined as a speed at which it is possible to travel without significantly departing from the traffic flow, on the basis of traffic flow information estimated from a plurality items of peripheral vehicle position information obtained from onboard sensors, is acquired as the speed limit of the travel path of the host vehicle.

A target vehicle speed generation method for generating a target vehicle speed of a host vehicle is generated in accordance with a speed limit of a travel path of the host vehicle, the target vehicle speed generation method comprising:

• acquiring the speed limit of the travel path of the host vehicle during travel;
• generating a target acceleration in accordance with the speed limit;
• and
• relaxing a limitation on acceleration during the generating of the target acceleration to a greater extent when the speed limit of the travel path of the host vehicle is high as compared to when the speed limit of the travel path of the host vehicle is low,
• during the acquiring of the speed limit of the travel path of the host vehicle, when a plurality of speed limits are acquired during travel, the lowest value of the plurality of speed limits is selected as the speed limit of the travel path of the host vehicle.

A device for generating a target vehicle speed of a driving-assisted host vehicle, the device comprising:

• a controller that generates a target vehicle speed of the host vehicle in accordance with a speed limit of a travel path of the host vehicle,
• the controller comprises
• a speed limit information acquisition unit that acquires the speed limit of the travel path of the host vehicle during travel, and
• a target vehicle speed generation unit that generates a target acceleration in accordance with the speed limit,
• during generation of the target acceleration, the target vehicle speed generation unit relaxes a limitation on acceleration to a greater extent when the speed limit of the travel path of the host vehicle is high as compared to when the speed limit of the travel path of the host vehicle is low, sets a first acceleration limit value that is increased correspondingly with an increase in the speed limit, sets a second acceleration limit value that is increased correspondingly with an increase in a difference in speed between the speed limit and a host-vehicle speed, and selects the lower of the first acceleration limit value and the second acceleration limit value as the acceleration limit value.