Adaptive cruise control system and method for automotive vehicle with inter-vehicle distance control function

Claim 2

An adaptive cruise control system for an automotive vehicle as claimed in claim 1, wherein the delay providing section (20) provides a dead time for one of the detected velocities of the vehicle and preceding vehicle which is used to set the target inter-vehicle distance.

Claim 3

An adaptive cruise control system for an automotive vehicle as claimed in claim 2, wherein the delay providing section (20) provides a larger dead time for one of the detected velocities of the vehicle and preceding vehicle which is used to set the target inter-vehicle distance as either one of the detected velocities of the vehicle or the preceding vehicle becomes smaller.

Claim 4

An adaptive cruise control system for an automotive vehicle as claimed in either claim 2 or claim 3, wherein the delay providing section (20) carries out a low-pass filtering for one of the velocities of the vehicle and the preceding vehicle which is used to set the target inter-vehicle distance and whose value is equal to or lower than a predetermined value.

Claim 5

An adaptive cruise control system for an automotive vehicle as claimed in claim 1, wherein the delay providing section (20) carries out a low-pass filtering for one of the velocities of the vehicle and the preceding vehicle which is used to set the target inter-vehicle distance.

Claim 6

An adaptive cruise control system for an automotive vehicle as claimed in claim 5, wherein a time constant(T) of the low-pass filter is set to become larger as one of the detected velocities of the vehicle and the preceding vehicle which is used to set the target inter-vehicle distance becomes lower.

Claim 7

An adaptive cruise control system for an automotive vehicle as claimed in either one of claim 5 or claim 6, wherein the delay providing section (20) carries out a low-pass filtering for one of the detected velocities of the vehicle and the preceding vehicle which is used to set the target inter-vehicle distance and whose value is equal to or lower than a predetermined value.

Claim 8

An adaptive cruise control system for an automotive vehicle as claimed in any one of the preceding claims 1 through 7, wherein the velocity detecting section comprises: a vehicular velocity detecting section (13L, 13R, 20) that detects the velocity of the vehicle (Vc); and a preceding vehicle velocity detecting section that detects the velocity of the preceding vehicle(V F )on the basis of a relative velocity (Vr) of the vehicle to the preceding vehicle and the velocity of the vehicle (V c ).

Claim 9

An adaptive cruise control system for an automotive vehicle as claimed in claim 4, wherein the delay providing section (20) provides a largest dead time for one of the velocities of the vehicle and the preceding vehicle which is used to set the target inter-vehicle distance when either one of the velocity of the host vehicle or the preceding vehicle is equal to or lower than a first predetermined velocity value, provides a second largest dead time for one of the velocities of the vehicle and the preceding vehicle which is used to set the target inter-vehicle distance when either one of the velocity of the vehicle or the preceding vehicle is higher than the first predetermined velocity value but is equal to or lower than a second predetermined velocity value, provides a third largest dead time for one of the velocities of the vehicle and the preceding vehicle which is used to set the target inter-vehicle distance when either one of the velocity of the host vehicle or the preceding vehicle is higher than the second predetermined velocity value but is equal to or lower than a third predetermined velocity value, provides a fourth largest dead time for one of the velocities of the vehicle and the preceding vehicle which is used to set the target inter-vehicle distance when either one of the velocity of the host vehicle or the preceding vehicle is higher than the third predetermined velocity value but is equal to or lower than a fourth predetermined velocity value, and provides a fifth largest dead time for one of the velocities of the vehicle and the preceding vehicle which is used to set the target inter-vehicle distance when either one of the velocity of the host vehicle or the preceding vehicle is higher than the fourth predetermined velocity value but is equal to or lower than a fifth predetermined velocity value.

Claim 10

An adaptive cruise control system for an automotive vehicle as claimed in claim 9, wherein the delay providing section provides (20) a fifth control number of times previously detected velocity of the preceding vehicle (V F5 ) for the detected velocity of the preceding vehicle (V FF ) used to set the target inter-vehicle distance when a presently detected velocity of the preceding vehicle (V F ) is equal to or lower than the first predetermined velocity value, provides a fourth control number of times previously detected velocity of the preceding vehicle (V F4 ) for the detected velocity of the preceding vehicle (V FF ) used to set the target inter-vehicle distance when the presently detected velocity of the preceding vehicle (V F ) is higher than the first predetermined velocity value but is equal to or lower than the second predetermined velocity value, provides a third control number of times previously detected velocity of the preceding vehicle (V F3 ) for the detected velocity of the preceding vehicle (V FF ) used to set the target inter-vehicle distance when the presently detected velocity of the preceding vehicle (V F ) is higher than the second predetermined velocity value but is equal to or lower than the third predetermined velocity value, provides a second control number of times previously detected velocity of the preceding vehicle (V F2 ) for the detected velocity of the preceding vehicle (V FF ) used to set the target inter-vehicle distance when the presently detected velocity of the preceding vehicle (V F ) is higher than the third predetermined velocity value but is equal to or lower than the fourth predetermined velocity value, and provides a once control number of time previously detected preceding vehicle (V F1 ) for the detected velocity of the preceding vehicle (V FF ) used to set the target inter-vehicle distance when the detected velocity of the preceding vehicle is higher than the fourth predetermined velocity value but is equal to or lower than the fifth predetermined velocity value.

Claim 11

An adaptive cruise control system for an automotive vehicle as claimed in claim 10, wherein the target inter-vehicle distance setting section (20) sets the target inter-vehicle distance D* as follows: D* = α · V FF + β, wherein V FF denotes the detected velocity of the preceding vehicle for which the delay is processed, α denotes a predetermined inter-vehicle time duration, and β denotes a predetermined distance at a time of a stop of the vehicle to reach to a position of the preceding vehicle and wherein the adaptive cruise control system further comprises: a difference value calculating section that calculates a difference of the set target inter-vehicle distance D* from the detected inter-vehicle distance D as follows: ΔD = D - D*; an inter-vehicle distance priority target acceleration/deceleration G D as follows: G D =F 1 · ΔD, wherein F 1 denotes a predetermined feedback gain; a target vehicular velocity calculating section that calculates a target velocity of the vehicle Vc* on the basis of a set vehicle speed Vs; a vehicular velocity priority target acceleration/deceleration calculating section that calculates a vehicular velocity priority target acceleration/deceleration G v on the basis of a difference between the target velocity of the vehicle Vc* and the detected velocity of the vehicle Vc; a target acceleration/deceleration calculating section that calculates a target acceleration/deceleration G* on the basis of the target inter-vehicle distance priority acceleration/deceleration G D , the vehicular velocity priority acceleration/deceleration G v , and whether the inter-vehicle distance detecting section detects the presence of the preceding vehicle; and an acceleration controlling section that performs an acceleration control of the vehicle on the basis of the target acceleration/deceleration G*.

Claim 12

An adaptive cruise control system for an automotive vehicle as claimed in claim 6, wherein the time constant (T) of the low-pass filter is set to give a maximum value (T 0 ) for the detected velocity of the vehicle used to set the target inter-vehicle distance when the detected velocity of the vehicle Vc is zero, is set to becomes smaller as the detected velocity of the vehicle (Vc) is increased, and is set to give zero when the detected velocity of the vehicle (Vc) becomes equal to the predetermined value.

Claim 13

An adaptive cruise control method for an automotive vehicle, comprising: detecting a presence of a preceding vehicle which is traveling ahead of the vehicle; detecting an inter-vehicle distance between the vehicle and the preceding vehicle; detecting a velocity of at least one of the vehicle and the preceding vehicle; controlling a traveling state of the vehicle on the basis of the detected inter-vehicle distance and a target inter-vehicle distance; providing a delay for one of the detected velocities of the vehicle and the preceding vehicle which is used to set the target inter-vehicle distance at a time of a detection of one of the velocities of the vehicle and the preceding vehicle which is used to set the target inter-vehicle distance; and setting the target inter-vehicle distance on the basis of the detected velocity of one of the vehicle and the preceding vehicle for which the delay is provided.