Travel control apparatus

• US 10,384,676 B2
• Filed: 02/01/2017
• Issued: 08/20/2019
• Est. Priority Date: 02/25/2016
• Status: Active Grant

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Watanabe, Yoshinori
• Primary Examiner(s): Do, Truc M
• Application Number:
  US15/421,697
• Publication Number:
  US 20170247029A1
• Time in Patent Office: 930 Days
• Field of Search: None
• CPC Class Codes: B60W 10/04 including control of propulsion units
• CPC Class Codes: B60W 10/20 including control of steering systems
• CPC Class Codes: B60W 2420/403 Image sensing, e.g. optical camera
• CPC Class Codes: B60W 2420/408 Radar; Laser, e.g. lidar
• CPC Class Codes: B60W 2520/10 Longitudinal speed
• CPC Class Codes: B60W 2552/20 Road profile, i.e. the change in elevation or curvature of a plurality of continuous road segments
• CPC Class Codes: B60W 2552/30 Road curve radius
• CPC Class Codes: B60W 2554/00 Input parameters relating to objects
• CPC Class Codes: B60W 2554/20 Static objects
• CPC Class Codes: B60W 2554/4029 Pedestrians
• CPC Class Codes: B60W 2554/4041 Position
• CPC Class Codes: B60W 2554/80 Spatial relation or speed relative to objects
• CPC Class Codes: B60W 2554/802 Longitudinal distance
• CPC Class Codes: B60W 2554/804 Relative longitudinal speed
• CPC Class Codes: B60W 2710/207 Steering angle of wheels
• CPC Class Codes: B60W 2720/10 Longitudinal speed
• CPC Class Codes: B60W 2720/24 Direction of travel
• CPC Class Codes: B60W 30/09 Taking automatic action to avoid collision, e.g. braking and steering
• CPC Class Codes: B60W 30/095 Predicting travel path or likelihood of collision
• CPC Class Codes: B60W 30/0956 the prediction being responsive to traffic or environmental parameters
• CPC Class Codes: B60W 30/12 : Lane keeping
• CPC Class Codes: B60W 30/16 : Control of distance between vehicles, e.g. keeping a distance to preceding vehicle
• CPC Class Codes: G05D 1/0212 : with means for defining a desired trajectory involving a plurality of land vehicles G05D1/0287
• CPC Class Codes: G05D 1/0219 : ensuring the processing of the whole working surface
• CPC Class Codes: G05D 1/0234 : using optical markers or beacons optical beacons per se G01S1/70
• CPC Class Codes: G05D 1/0238 : using obstacle or wall sensors G05D1/0246 and G05D1/0289 take precedence; lidar systems designed for anti-collision purposes G01S17/93
• CPC Class Codes: G08G 1/16 : Anti-collision systems road vehicle drive control systems for predicting or avoiding probable or impending collision otherwise than by control of a particular sub-unit B60W30/08
• CPC Class Codes: G08G 1/165 : for passive traffic, e.g. including static obstacles, trees
• CPC Class Codes: G08G 1/166 : for active traffic, e.g. moving vehicles, pedestrians, bikes
• CPC Class Codes: G08G 1/167 : Driving aids for lane monitoring, lane changing, e.g. blind spot detection

Abstract

A travel control apparatus includes: a transformation unit configured to project the lane and object on a lane coordinate system in which a center line of the lane is a first coordinate axis and an axis orthogonal to the first coordinate axis is a second coordinate axis by performing a coordinate transformation based on the shape of the lane and the position of the object in a plane coordinate system; an area calculation unit configured to calculate a travelable area in which the vehicle can travel in the lane coordinate system; a travel trajectory generation unit configured to perform an inverse transformation of the coordinate transformation by the transformation unit based on the travelable area, and to generate a travel trajectory of the vehicle in the plane coordinate system; and a control unit configured to perform a steering control on the vehicle.

Claims

1. A travel control apparatus comprising:

a processor configured to;

recognize, in a first coordinate system that is a plane coordinate system, plane coordinate positions of lane boundary lines in front a vehicle on lane in which the vehicle travels;

recognize, in the plane coordinate system, a plane coordinate travelling position of the vehicle in the lane;

recognize, in the plane coordinate system, a plane coordinate position of an object present around the vehicle;

perform a coordinate transformation process that projects the lane boundary lines and the object recognized in the plane coordinate system onto a second coordinate system that is different from the first coordinate system, the second coordinate system being a lane coordinate system in which a center line of the lane is a first coordinate axis and an axis orthogonal to the first coordinate axis is a second coordinate axis;

calculate a travelable area in which the vehicle can travel in the lane coordinate system based on the projected lane boundary lines and the projected object in the lane coordinate system;

generate a travel trajectory of the vehicle in the plane coordinate system based on the calculated travelable area and the travelling position; and

perform a steering control on the vehicle based on the generated travel trajectory.

2. The travel control apparatus according to claim 1, wherein

the processor is further configured to:

detect a speed of the vehicle;

detect a speed of the object;

correct the position of the projected object in the lane coordinate system to a temporal position which is a position of the object in the lane coordinate system at a time when the vehicle overtakes the object, based on the position and speed of the object in the lane coordinate system and the travelling position and speed of the vehicle in the lane coordinate system; and

calculate the travelable area based on the temporal position of the object.

3. The travel control apparatus according to claim 2, wherein the processor is further configured to:

determine whether or not the travelable area calculated based on the temporal position of the object includes a narrow area in which a width in the second coordinate axis direction is equal to or smaller than a width threshold value;

calculate the travelable area again while excluding the object when the processor determines that the travelable area includes the narrow area; and

perform a speed control to follow the excluded object.

4. The travel control apparatus according to claim 3, wherein the processor is further configured to:

perform processing to correct the position of the object in the lane coordinate system to the temporal position when positions and speeds of each of a plurality of objects are detected;

determine whether or not the travelable area calculated based on the temporal positions of the plurality of objects includes the narrow area;

calculate the travelable area again based on the remaining object after excluding the object having the highest speed among the plurality of objects forming the narrow area when the processor determines that the travelable area includes the narrow area; and

perform the speed control to follow the excluded object having the highest speed.

5. The travel control apparatus according to claim 1, wherein the coordinate transformation process includes:

defining object intersection points by drawing orthogonal lines from end points of the object to the center line of the lane, respectively;

defining a vehicle intersection point by drawing an orthogonal line from a center of gravity position of the vehicle to the center line of the lane; and

calculating distances from the defined vehicle intersection point to the object intersection points, respectively, on the center line of the lane.

6. The travel control apparatus according to claim 5, wherein the coordinate transformation process uses a curvature function.

7. The travel control apparatus according to claim 1, wherein the plane coordinate system is a fixed coordinate system.

8. The travel control apparatus according to claim 1, wherein the plane coordinate system is a coordinate system having two axes orthogonal to each other with the position of the vehicle as an origin.

9. The travel control apparatus according to claim 1, wherein the lane coordinate system is a coordinate system associated with a shape of the lane.