Vehicle speed control apparatus

• US 20020032514A1
• Filed: 10/09/2001
• Published: 03/14/2002
• Est. Priority Date: 12/01/1997
• Status: Active Grant

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Takenaga, Hiroshi, Minowa, Toshimichi, Kuroda, Hiroshi, Kayano, Mitsuo, Kuragaki, Satoru, Takano, Kazuaki
• Granted Patent: US 6,473,685 B2
• Time in Patent Office: Days
• US Class Current: 701/96
• CPC Class Codes: B60K 31/0008 including means for detecting potential obstacles in vehicle path
• CPC Class Codes: B60K 31/0066 responsive to vehicle path curvature
• CPC Class Codes: B60T 7/22 initiated by contact of vehicle, e.g. bumper, with an external object, e.g. another vehicle , or by means of contactless obstacle detectors mounted on the vehicle
• CPC Class Codes: B60W 10/10 including control of change-speed gearings
• CPC Class Codes: B60W 10/184 with wheel brakes
• CPC Class Codes: B60W 2520/14 Yaw
• 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 2554/802 Longitudinal distance
• CPC Class Codes: B60W 2554/804 Relative longitudinal speed
• CPC Class Codes: B60W 2554/805 Azimuth angle
• CPC Class Codes: B60W 2556/50 of positioning data, e.g. GPS [Global Positioning System] data
• CPC Class Codes: B60W 2720/106 Longitudinal acceleration
• CPC Class Codes: B60W 30/045 Improving turning performance
• CPC Class Codes: B60W 30/143 Speed control B60W30/16 takes precedence
• CPC Class Codes: B60W 30/16 Control of distance between vehicles, e.g. keeping a distance to preceding vehicle
• CPC Class Codes: B60W 30/18145 Cornering
• CPC Class Codes: F02D 29/02 peculiar to engines driving vehicles; peculiar to engines driving variable pitch propellers
• CPC Class Codes: G08G 1/167 Driving aids for lane monitoring, lane changing, e.g. blind spot detection

Abstract

A vehicle speed control apparatus for allowing a host vehicle trailing a preceding vehicle to accelerate and decelerate without causing discomfort to the host vehicle driver. While the host vehicle is trailing the preceding vehicle, the apparatus on board the host vehicle stores the speed of the preceding vehicle entering a curve ahead as well as a headway distance of the host vehicle to the preceding vehicle. Upon reaching the curve, the host vehicle is controlled by the apparatus to enter the curve at a speed not in excess of the stored speed of the preceding vehicle.

Claims

1. A vehicle speed control apparatus comprising:

detecting means for detecting a headway distance and a relative speed of a host vehicle in relation to a preceding vehicle;

detecting means for detecting an own speed of said host vehicle;

computing means for computing a speed of said preceding vehicle based on said own speed and said relative speed of said host vehicle; and

controlling means which stores the speed of said preceding vehicle passing a given point and which controls at least one of a throttle valve device, a transmission device and a braking device so that said own speed of said host vehicle passing said point does not exceed the stored speed of said preceding vehicle.

2. A vehicle speed control apparatus according to claim 1, wherein said controlling means controls said own speed of said host vehicle if said preceding vehicle directionally deviates by a predetermined angle from a frontal direction of said host vehicle.

3. A vehicle speed control apparatus according to claim 1, wherein said control means controls said own speed of said host vehicle if said preceding vehicle is found turning in direction.

4. A vehicle speed control apparatus according to claim 1, wherein said controlling means controls said own speed of said host vehicle so that said headway distance to said preceding vehicle exceeds a predetermined value.

5. A vehicle speed control apparatus comprising:

detecting means for detecting a headway distance and a relative speed of a host vehicle in relation to a preceding vehicle;

detecting means for detecting an own speed and a yaw rate of said host vehicle;

computing means for computing a speed of said preceding vehicle based on said own speed and said relative speed of said host vehicle; and

controlling means which, if said yaw rate of said host vehicle is in excess of a predetermined value, stores the speed of said preceding vehicle passing a given point, said controlling means further controlling at least one of a throttle valve device, a transmission device and a braking device so that said own speed of said host vehicle passing said point does not exceed both a speed determined by said yaw rate of said host device and the stored speed of said preceding vehicle.

6. A vehicle speed control apparatus comprising:

detecting means for detecting a headway distance and a relative speed of a host vehicle in relation to a preceding vehicle;

detecting means for detecting an own speed and a yaw rate of said host vehicle;

computing means for computing a speed of said preceding vehicle based on said own speed and said relative speed of said host vehicle; and

controlling means which, if host vehicles loses sight of said preceding vehicle and if said yaw rate of said host vehicle is in excess of a predetermined value, then controls at least one of a throttle valve device, a transmission device and a braking device so that said own speed of said host vehicle does not exceed both the speed of said preceding vehicle in effect when said host vehicle lost sight of said preceding vehicle and a speed determined by said yaw rate of said host device.

7. A vehicle speed control apparatus comprising:

detecting means for detecting headway distances and directions of a host vehicle in relation to a plurality of preceding vehicles; and

judging means which, if said plurality of preceding vehicles are found turning in the same direction, judges that said host vehicle is heading toward a curved road.

8. A vehicle speed control apparatus comprising:

detecting means for detecting headway distances, relative speeds and directions of a host vehicle in relation to a plurality of preceding vehicles;

detecting means for detecting an own speed of said host vehicle;

computing means for computing speeds of said plurality of preceding vehicles based on said own speed and said relative speeds of said host vehicle; and

controlling means which, if said plurality of preceding vehicles are found turning in the same direction, then judges that said host vehicle is heading toward a curved road and controls at least one of a throttle valve device, a transmission device and a braking device so that said own speed of said host vehicle entering said curved road does not exceed the speed of the immediately preceding vehicle having entered said curved road earlier.

9. A vehicle speed control apparatus comprising:

detecting means for detecting headway distances, relative speeds and directions of a host vehicle in relation to a plurality of preceding vehicles;

detecting means for detecting an own speed of said host vehicle;

computing means for computing speeds of said plurality of preceding vehicles based on said own speed and said relative speeds of said host vehicle; and

controlling means which, if said plurality of preceding vehicles are found turning in different directions, then controls at least one of a throttle valve device, a transmission device and a braking device so as to maintain said own speed of said host vehicle for a predetermined period of time.

10. A vehicle speed control apparatus comprising:

detecting means for detecting headway distances, relative speeds and directions of a host vehicle in relation to a plurality of preceding vehicles;

detecting means for detecting an own speed of said host vehicle;

computing means for computing speeds of said plurality of preceding vehicles based on said own speed and said relative speeds of said host vehicle; and

controlling means which, if said plurality of preceding vehicles are found turning in different directions, then acquires road information about a currently-taken road from a navigation device, said controlling means further determining a target own speed of said host vehicle based on the computed speeds of said plurality of preceding vehicles and on the acquired road information.

11. A vehicle speed control apparatus according to claim 10, wherein said road information includes road branch information;

wherein, if said road information points to road branches ahead, then said controlling means allows said host vehicle to trail the immediately preceding vehicle; and

wherein, if said road information indicates absence of any road branches ahead, then said controlling means controls at least one of a throttle valve device, a transmission device and a braking device so as to maintain said own speed of said host vehicle for a predetermined period of time.

12. A vehicle speed control apparatus according to claim 10, wherein said road information includes road lane information;

wherein, if a one-side single-lane road is currently taken, then said controlling means allows said host vehicle to trail the immediately preceding vehicle; and

wherein, if a one-side multiple-lane road is currently taken, then said controlling means controls at least one of a throttle valve device, a transmission device and a braking device so as to maintain said own speed of said host vehicle for a predetermined period of time.

15. A vehicle speed control apparatus according to claim 14, further comprising controlling means which, if a difference between the yaw rate of said preceding vehicle and the yaw rate of said host vehicle is judged to exceed a predetermined value, then controls at least one of a throttle valve device, a transmission device and a braking device so as to stop said host vehicle from trailing said preceding vehicle and to maintain said own speed of said host vehicle for a predetermined period of time.

16. A vehicle speed control apparatus according to claim 14, further comprising controlling means which, if a difference between the yaw rate of said preceding vehicle and the yaw rate of said host vehicle is judged to be below a predetermined value, then stores a speed of said preceding vehicle passing a given point and controls at least one of a throttle valve device, a transmission device and a braking device so that said own speed of said host vehicle passing said point does not exceed the stored speed of said preceding vehicle.

13. A vehicle speed control apparatus comprising:

detecting means for detecting a headway distance, a relative speed and a direction of a host vehicle in relation to a preceding vehicle;

detecting means for detecting an own speed and a yaw rate of said host vehicle;

computing means for computing a speed vector of said preceding vehicle with respect to said host vehicle on the basis of said relative speed and said direction; and

judging means for judging whether said preceding vehicle is passing a curve.

14. A vehicle speed control apparatus comprising:

detecting means for detecting a headway distance, a relative speed and a direction of a host vehicle in relation to a preceding vehicle;

trailing means for allowing said host vehicle to trail said preceding vehicle;

detecting means for detecting an own speed and a yaw rate of said host vehicle;

computing means for computing a speed vector of said preceding vehicle with respect to said host vehicle on the basis of said relative speed and said direction;

computing means for computing a yaw rate of said preceding vehicle on the basis of changes in said speed vector; and

comparing means which, if the yaw rate of said preceding vehicle passing a given point is judged to be in excess of a predetermined value, then stores the yaw rate of said preceding vehicle, said comparing means further comparing the stored yaw rate of said preceding vehicle with the detected yaw rate of said host vehicle when said host vehicle reaches the point at which the yaw rate of said preceding vehicle was stored.