Cruise control plan evaluation device and method

• US 20100010699A1
• Filed: 11/01/2007
• Published: 01/14/2010
• Est. Priority Date: 11/01/2006
• Status: Active Grant

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Doi, Tomoyuki, Taguchi, Koji
• Granted Patent: US 9,224,299 B2
• Time in Patent Office: Days
• US Class Current: 701/23
• CPC Class Codes: B60W 2552/05 Type of road, e.g. motorways, local streets, paved or unpaved roads
• CPC Class Codes: B60W 2552/10 Number of lanes
• CPC Class Codes: B60W 2554/00 Input parameters relating to objects
• CPC Class Codes: B60W 2554/80 Spatial relation or speed relative to objects
• CPC Class Codes: B60W 30/08 Active safety systems predicting or avoiding probable or impending collision or attempting to minimise its consequences
• CPC Class Codes: B60W 30/0956 the prediction being responsive to traffic or environmental parameters
• CPC Class Codes: B60W 50/0097 Predicting future conditions
• CPC Class Codes: B62D 6/00 Arrangements for automatically controlling steering depending on driving conditions sensed and responded to, e.g. control circuits means for initiating a change in direction B62D1/00; steering valves B62D5/06; combined with means for inclining the vehicle body or wheels on bends B62D9/00
• CPC Class Codes: G08G 1/163 involving continuous checking
• CPC Class Codes: G08G 1/167 Driving aids for lane monitoring, lane changing, e.g. blind spot detection

Abstract

A cruise control plan evaluation device (10) that evaluates safety of a cruise control plan for an automatically-operated vehicle includes: a behavior prediction unit (16a) that predicts a behavior that may be exhibited by a nearby vehicle, which is present near the automatically-operated vehicle, at a given time point; a position prediction unit (16b) that predicts a position of the nearby vehicle after the given time point based on a position of the nearby vehicle at the given time point and the behavior predicted by the behavior prediction unit (16a); and an evaluation unit (20) that evaluates the safety of the cruise control plan based on the position of the nearby vehicle predicted by the position prediction unit (16b) and a position that is reached by the automatically-operated vehicle according to the cruise control plan.

Claims

1. A cruise control plan evaluation device that evaluates safety of a cruise control plan for an automatically-operated vehicle, comprising:

a behavior prediction unit that predicts a behavior that may be exhibited by a nearby vehicle, which is present near the automatically-operated vehicle, at a given time point;

a position prediction unit that predicts a position of the nearby vehicle after the given time point based on a position of the nearby vehicle at the given time point and the behavior predicted by the behavior prediction unit; and

an evaluation unit that evaluates the safety of the cruise control plan based on the position of the nearby vehicle predicted by the position prediction unit and a position that is reached by the automatically-operated vehicle according to the cruise control plan.

2. The cruise control plan evaluation device according to claim 1, wherein

the behavior prediction unit predicts the behavior of the nearby vehicle based on at least information concerning a road shape.

3. The cruise control plan evaluation device according to claim 1, further comprising:

a cruise control plan preparation unit that prepares multiple cruise control plans for the automatically-operated vehicle; and

a cruise control plan selection unit that selects the cruise control plan to be implemented from among the multiple cruise control plans based on results of evaluations made by the evaluation unit.

4. The cruise control plan evaluation device according to claim 1, further comprising:

a cruise control plan preparation unit that prepares a cruise control plan for the automatically-operated vehicle, wherein

the cruise control plan preparation unit modifies the cruise control plan based on a result of evaluation made by the evaluation unit.

5. The cruise control plan evaluation device according to claim 1, wherein

the behavior prediction unit predicts the behavior that may be exhibited by the nearby vehicle and also estimates a probability that the nearby vehicle exhibits the behavior.

6. The cruise control plan evaluation device according to claim 5, wherein

the evaluation unit includes:

a predicted vehicle-presence region drawing-up unit that draws up a predicted vehicle-presence region that indicates a region, in which the nearby vehicle is predicted to be present, using a probability distribution based on the position of the nearby vehicle predicted by the position prediction unit and the probability estimated by the behavior prediction unit;

a contact impermissible region drawing-up unit that draws up a contact impermissible region that indicates a region, which needs to be maintained to prevent contact between the automatically-operated vehicle and the nearby vehicle, using a probability distribution in a manner such that an outline of the contact impermissible region surrounds the automatically-operated vehicle; and

a determination unit that determines that the cruise control plan is safe when a result of multiply-and-accumulation of the predicted vehicle-presence region and the contact impermissible region is equal to or lower than a first threshold value at any time point.

7. The cruise control plan evaluation device according to claim 6, wherein

the evaluation unit includes an emergency contact-avoidance ensuring region drawing-up unit that draws up an emergency contact-avoidance ensuring region that indicates a region, which needs to be maintained to prevent contact between the automatically-operated vehicle and the nearby vehicle in an emergency, using a probability distribution in a manner such that an outline of the emergency contact-avoidance ensuring region surrounds the automatically-operated vehicle, and

the determination unit determines that the cruise control plan is safe when a result of multiply-and-accumulation of the predicted vehicle-presence region and the emergency contact-avoidance ensuring region is equal to or lower than a second threshold value at any time point.

8. A cruise control plan evaluation method for evaluating safety of a cruise control plan for an automatically-operated vehicle, comprising:

predicting a behavior that may be exhibited by a nearby vehicle, which is present near the automatically-operated vehicle, at a given time point;

predicting a position of the nearby vehicle after the given time point based on a position of the nearby vehicle at the given time point and the predicted behavior; and

evaluating the safety of the cruise control plan based on the predicted position of the nearby vehicle and a position that is reached by the automatically-operated vehicle according to the cruise control plan.

9. The cruise control plan evaluation method according to claim 8, wherein

the behavior of the nearby vehicle is predicted based on at least information concerning a road shape.

10. The cruise control plan evaluation method according to claim 8, further comprising:

preparing multiple cruise control plans for the automatically-operated vehicle; and

selecting the cruise control plan to be implemented from among the multiple cruise control plans based on results of evaluations.

11. The cruise control plan evaluation method according to claim 8, further comprising:

preparing a cruise control plan for the automatically-operated vehicle; and

modifying the cruise control plan based on a result of evaluation.

12. The cruise control plan evaluation method according to claim 8, wherein

the behavior that may be exhibited by the nearby vehicle is predicted and a probability that the nearby vehicle exhibits the behavior is also estimated.

13. The cruise control plan evaluation method according to claim 12, wherein

a step of evaluating the cruise control plan includes:

drawing up a predicted vehicle-presence region that indicates a region, in which the nearby vehicle is predicted to be present, using a probability distribution based on the predicted position of the nearby vehicle and the estimated probability; and

drawing up a contact impermissible region that indicates a region, which needs to be maintained to prevent contact between the automatically-operated vehicle and the nearby vehicle, using a probability distribution in a manner such that an outline of the contact impermissible region surrounds the automatically-operated vehicle; and

determining that the cruise control plan is safe when a result of multiply-and-accumulation of the predicted vehicle-presence region and the contact impermissible region is equal to or lower than a first threshold value at any time point.

14. The cruise control plan evaluation method according to claim 13, wherein

the step of evaluating the safety of the cruise control plan further includes:

drawing up an emergency contact-avoidance ensuring region that indicates a region, which needs to be maintained to prevent contact between the automatically-operated vehicle and the nearby vehicle in an emergency, using a probability distribution in a manner such that an outline of the emergency contact-avoidance ensuring region surrounds the automatically-operated vehicle; and

determining that the cruise control plan is safe when a result of multiply-and-accumulation of the predicted vehicle-presence region and the emergency contact-avoidance ensuring region is equal to or lower than a second threshold value at any time point.