# US 11,305,768 B2 · Method and device for controlling autonomously driven vehicle > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,305,768 B2 - Document ID: US11305768B2 - Status: Granted - Kind: B2 - Application number: 16/977,551 - Filed: 2018-03-27 - Published: 2021-01-07 - Granted: 2022-04-19 - Earliest claimed: 2018-03-27 - Assignees: Nissan Motor Co., Ltd. - Applicants: Nissan Motor Co., Ltd. - Inventors: Hajime Miura - Web page: https://patentgrep.com/patent/US11305768B2 ## CPC - B60W 30/143: {Speed control (B60W30/16 takes precedence)} - B60W 30/162: {Speed limiting therefor} - B60W 10/06: including control of combustion engines - B60W 10/08: including control of electric propulsion units, e.g. motors or generators - B60W 10/184: with wheel brakes - B60W 30/146: {Speed limiting} - B60W 30/16: Control of distance between vehicles, e.g. keeping a distance to preceding vehicle - B60W 30/188: Controlling power parameters of the driveline, e.g. determining the required power - B60W 60/0023: {in response to energy consumption} - B60W 2520/10: Longitudinal speed - B60W 2520/105: Longitudinal acceleration - B60W 2540/215: Selection or confirmation of options - B60W 2552/05: Type of road, e.g. motorways, local streets, paved or unpaved roads - B60W 2554/404: Characteristics - B60W 2554/802: Longitudinal distance - B60W 2554/804: Relative longitudinal speed - B60W 2720/106: Longitudinal acceleration - Y02T 10/40: Engine management systems - Y02T 10/84: Data processing systems or methods, management, administration - B60W: CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT - Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION ## Abstract An acceleration rate is controlled so that a vehicle speed during autonomous driving is caused to approach a target vehicle speed. When a host vehicle has caught up with another vehicle traveling ahead of the host vehicle, the vehicle speed of the host vehicle is limited in accordance with a headway distance to the other vehicle. An acceleration rate is changed in accordance with a frequency with which the host vehicle catches up to a preceding vehicle, which is another vehicle immediately ahead of the host vehicle, and to another vehicle ahead of the preceding vehicle. ## Claims ### Claim 1 A control method for an autonomously driven vehicle, the control method comprising: controlling an acceleration rate of a host vehicle so that a vehicle speed during autonomous driving is caused to approach a target vehicle speed; upon the host vehicle catching up with another vehicle traveling ahead, limit the vehicle speed of the host vehicle in accordance with a headway distance to another vehicle; calculating an acceleration continuation time from a start to an end of acceleration when the host vehicle catches up to the other vehicle traveling ahead; and changing the acceleration rate upon the host vehicle approaching the target vehicle speed in accordance with the acceleration continuation time that was calculated such that the acceleration rate is increased by a greater amount commensurately as the acceleration continuation time becomes longer. ### Claim 2 (depends on 1) The control method according to claim 1, wherein the acceleration rate is reduced when the acceleration continuation time is less than a predetermined time. ### Claim 3 (depends on 1) The control method according to claim 1, wherein the acceleration rate of the host vehicle is controlled according to a first acceleration rate characteristic yielding a high acceleration rate at the same vehicle speed or a second acceleration rate characteristic yielding an acceleration rate lower than the first acceleration rate characteristic, and the acceleration rate is changed by switching between the first acceleration rate characteristic and the second acceleration rate characteristic in accordance with the acceleration continuation time. ### Claim 4 (depends on 3) The control method according to claim 3, wherein during travel under the first acceleration rate characteristic, a switch is made to the second acceleration rate characteristic when the acceleration continuation time is less than a predetermined time; and during travel under the second acceleration rate characteristic, a switch is made to the first acceleration rate characteristic when the acceleration continuation time is longer than a predetermined time. ### Claim 5 (depends on 3) The control method according to claim 3, wherein instead of the switching between the first acceleration rate characteristic and the second acceleration rate characteristic, the acceleration rate characteristics are revised in accordance with the acceleration continuation time; during travel under the first acceleration rate characteristic, the acceleration rate yielded by the first acceleration rate characteristic is reduced when the acceleration continuation time is less than a predetermined time; and during travel under the second acceleration rate characteristic, the acceleration rate yielded by the second acceleration rate characteristic is increased when the acceleration continuation time is longer than a predetermined time. ### Claim 6 A control method for an autonomously driven vehicle, the control method comprising: controlling an acceleration rate of a host vehicle so that a vehicle speed during autonomous driving is caused to approach a target vehicle speed, the acceleration rate being controlled by switching between a first acceleration rate characteristic yielding a high acceleration rate at the same vehicle speed and a second acceleration rate characteristic yielding a lower acceleration rate than the first acceleration rate characteristic; determining an end of acceleration performed according to the acceleration rate characteristics both during travel under the first acceleration rate characteristic and during travel under the second acceleration rate characteristic; during traveling under the second acceleration rate characteristic, when the host vehicle has reached the target vehicle speed and then caught up with another vehicle traveling ahead of the host vehicle at a vehicle speed lower than the target vehicle speed, a switch is made to the first acceleration rate characteristic or the acceleration rate yielded by the second acceleration rate characteristic is increased; and during traveling under the first acceleration rate characteristic, when the host vehicle has reached the target vehicle speed and then caught up with the other vehicle, a switch is made to the second acceleration rate characteristic or the acceleration rate yielded by the first acceleration rate characteristic is reduced. ### Claim 7 A device for controlling an autonomously driven vehicle, the device comprising: a vehicle drive source; and a controller that controls the drive source, the controller comprising an acceleration control unit that controls an acceleration rate of a host vehicle so that a vehicle speed during autonomous driving is caused to approach a target vehicle speed, and a vehicle-speed-limiting unit that limits the vehicle speed of the host vehicle in accordance with a headway distance to another vehicle traveling ahead of the host vehicle when the host vehicle has caught up with the other vehicle; and the acceleration control unit calculating an acceleration continuation time from a start to an end of acceleration when the host vehicle catches is up to the other vehicle traveling ahead, and changing the acceleration rate upon the host vehicle approaching the target vehicle speed in accordance with the acceleration continuation time that was calculated such that the acceleration rate is increased by a greater amount commensurately as the acceleration continuation time becomes longer. ### Claim 8 A control method for an autonomously driven vehicle, the control method comprising: controlling an acceleration rate of a host vehicle so that a vehicle speed during autonomous driving is caused to approach a target vehicle speed; upon the host vehicle catching up with another vehicle traveling ahead, limit the vehicle speed of the host vehicle in accordance with a headway distance to another vehicle; calculating an acceleration continuation time from a start to an end of acceleration when the host vehicle catches up to the other vehicle traveling ahead; and changing the acceleration rate upon the host vehicle approaching the target vehicle speed in accordance with the acceleration continuation time that was calculated such that the acceleration rate is increased by a greater amount commensurately as the acceleration continuation time becomes longer.