Vehicle warning apparatus for generating warning signal depending upon operator's brake operating characteristics

• US 6,696,929 B2
• Filed: 11/23/2001
• Issued: 02/24/2004
• Est. Priority Date: 11/24/2000
• Status: Expired due to Term

• Current Assignee: Aisin Seiki Co., Ltd. (Aisin Corp.), Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Aisin Seiki Co., Ltd. (Aisin Corp.), Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Nagiri, Sueharu, Watanabe, Kazuya, Sakabe, Masahiko, Nakasho, Takayuki, Igaki, Munenaga, Nonaka, Masakatsu, Kuzuya, Keiji
• Primary Examiner(s): Hofsass, Jeffery
• Assistant Examiner(s): Previl, Daniel
• Application Number:
  US09/990,292
• Publication Number:
  US 20020101337A1
• Time in Patent Office: 823 Days
• Field of Search: 340/435, 340/436, 340/441, 340/444, 340/452, 340/453, 340/426.32, 340/426.24, 340/426.25, 340/457.3, 340/459, 340/466, 340/467, 340/464, 340/477, 340/903, 340/904, 340/905
• US Class Current: 340/435
• CPC Class Codes: B60K 28/066 actuating a signalling device B60K28/063 takes precedence
• CPC Class Codes: B60K 31/0008 including means for detecting potential obstacles in vehicle path
• CPC Class Codes: B60T 17/18 Safety devices; Monitoring
• 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 2050/143 Alarm means
• CPC Class Codes: B60W 2552/40 Coefficient of friction
• CPC Class Codes: G08G 1/162 event-triggered

Abstract

Warning apparatus for an automotive vehicle, operable to generate a warning signal when a distance between the vehicle and an object in front of the vehicle is shorter than a predetermined threshold value, the apparatus including a characteristic-value storage portion which stores at least one characteristic-value relationship between at least two of a plurality of brake operating characteristic values relating to a braking operation by an operator of the vehicle to brake the vehicle, and a threshold-value determining portion operable to determine the threshold value of the distance, on the basis of at least one of an estimated braking state of the vehicle estimated on the basis of the characteristic-value relationship stored in the characteristic-value storage portion, a running-state quantity indicative of a running state of the vehicle, and a moving-state quantity indicative of a moving state of the object.

Claims

1. A warning apparatus for an automotive vehicle, operable to generate a warning signal when a distance between the vehicle and an object existing in front of the vehicle is shorter than a predetermined threshold value, comprising:

a characteristic-value storage portion which stores at least one characteristic-value relationship between at least two of a plurality of brake operating characteristic values relating to a braking operation by an operator of the vehicle to brake the vehicle; and

a threshold-value determining portion operable to determine said threshold value of said distance, on the basis of;

an estimated braking state of the vehicle estimated on the basis of said at least one characteristic-value relationship stored in said characteristic-value storage portion; and

at least one of a running-state quantity indicative of a running state of the vehicle, and a moving-state quantity indicative of a moving state of said object,

wherein said at least one characteristic-value relationship stored in said characteristic-value storage portion is represented by an envelope of experimental data indicative of said at least two of said plurality of brake operating characteristic values.

2. A warning apparatus according to claim 1, wherein said characteristic-value storage portion stores at least two characteristic-value relationships of one of said plurality of brake operating characteristic values with respective at least two other characteristic values of said plurality of brake operating characteristic values, and said threshold-value determining portion is operable to estimate at least two braking-state quantities indicative of a braking state of the present vehicle, on the basis of said one brake operating characteristic value and said characteristic-value relationships.

3. A warning apparatus according to claim 1, wherein said characteristic-value storage portion stores at least one characteristic-value relationship selected from a plurality of relationships between or among at least two of;

(a) an operating-speed quantity relating to a speed of said braking operation by the operator to brake the vehicle;

(b) a vehicle-deceleration quantity relating to a deceleration value of the vehicle as a result of said braking operation by the operator to brake the vehicle; and

(c) a relative-position quantity relating to a relative position between the vehicle and said object upon said braking operation.

4. A warning apparatus according to claim 1, wherein said characteristic-value storage portion stores at least one characteristic-value relationship selected from a plurality of relationships between or among at least two of:

(a) a desired-safety-margin quantity relating to a safety margin desired by the operator in connection with said braking operation by the operator to brake the vehicle, (b) a required-vehicle-deceleration quantity relating to a required deceleration value of the vehicle as felt by the operator upon said braking operation, and (c) a critical-relative-position quantity relating to a relative position between the vehicle and said object at which the operator feels it necessary to initiate said braking operation.

5. A warning apparatus according to claim 1, wherein said characteristic-value storage portion stores at least one characteristic-value relationship selected from a plurality of relationships between or among at least two of:

(a) a promptness quantity relating to promptness of the operator to perform said braking operation;

(b) an operating-force quantity relating to an operating force to be produced by the operator to perform said braking operation; and

(c) a critical-relative-position quantity relating to a relative position between the vehicle and said object at which the operator feels it necessary to initiate said braking operation.

6. A warning apparatus according to claim 1, wherein said characteristic-value storage portion stores at least one of:

(a) a relationship between a braking-delay time between a moment at which the operator feels it necessary to initiate said braking operation and a moment at which said braking operation is actually initiated, and a deceleration value of the vehicle to be established by said braking operation; and

(b) a relationship between said braking-delay time and a relative-position quantity relating to a relative position between the vehicle and said object.

7. A warning apparatus according to claim 1, further comprising a characteristic-value setting portion manually operable by the operator to set at least one of said at least two of said plurality of brake operating characteristic values, and said threshold-value determining portion is operable to obtain said estimated braking state of the vehicle on the basis of said at least one brake operating characteristic value set by said characteristic-value setting portion and said at least one characteristic-value relationship stored in said characteristic-value storage portion, said threshold-value determining portion determining said threshold value of said distance on the basis of said estimated braking state obtained.

8. A warning apparatus according to claim 1, further comprising:

a friction-coefficient obtaining portion operable to obtain a friction coefficient of a roadway surface on which the vehicle is running; and

a characteristic-value-relationship determining portion operable to determine said at least one characteristic-value relationship on the basis of said friction coefficient obtained by said friction-coefficient obtaining portion.

9. A warning apparatus according to claim 1, further comprising:

a running-environment obtaining portion operable to obtain a running environment of the vehicle; and

a characteristic-value-relationship determining portion operable to determine said at least one characteristic-value relationship on the basis of said running environment obtained by said running-environment obtaining portion.

10. A warning apparatus according to claim 1, further comprising:

a running-state obtaining portion operable to obtain said running state of the vehicle; and

a characteristic-value-relationship determining portion operable to determine said at least one characteristic-value relationship on the basis of said running state obtained by said running-state obtaining portion.

11. A warning apparatus according to claim 1, wherein the vehicle has a controlled running mode in which said running state is controlled on the basis of a relative-position quantity relating to a relative position between the vehicle and said object, and said threshold-value determining portion determines said threshold value of said distance such that the determined threshold value is larger when the vehicle is running in said controlled running mode, than when the vehicle is not running in said controlled running mode.

12. A warning apparatus according to claim 1, further comprising a safety detecting portion operable to determine whether a positional relationship between the vehicle and said object falls within a predetermined safe region, and said threshold-value determining portion determines said threshold value of said distance when said safety detecting portion determines that said positional relationship does not fall within said safe region.

13. A warning apparatus according to claim 1, further comprising a running control portion operable to control said running state of the vehicle on the basis of a relative-position quantity relating to a relative position between the vehicle and said object.

14. A warning apparatus according to claim 1, wherein said at least two of said plurality of brake operating characteristic values include (i) a braking-delay time between a moment at which the operator feels it necessary to initiate said braking operation and a moment at which said braking is actually initiated, (ii) a deceleration value of the vehicle to be established by said braking operation, and (iii) a relative-position quantity relating to a relative position between the vehicle and said object, and said at least one characteristic-value relationship includes a first relationship between said braking-delay time and said deceleration value, and a second relationship between said braking-delay time and said relative-position quantity.

15. A warning apparatus according to claim 14, wherein said first relationship is represented by an envelope of highest values of said deceleration value obtained by experiment for each value of said braking-delay time.

16. A warning apparatus according to claim 14, wherein said second relationship is represented by an envelope of smallest value of said relative-position quantity obtained by experiment for each value of said braking-delay time.

17. A warning apparatus according to claim 14, further comprising a characteristic-value setting portion manually operable by the operator to set said braking-delay time, and said threshold-value determining portion is operable to obtain said estimated braking state of the vehicle on the basis of said braking-delay time set by said characteristic-value setting portion, and said first and second relationships stored in said characteristic-value storage portion.