JP5018544B2 - Vehicle travel control device - Google Patents

Description

  The present invention generally relates to a vehicular travel control device that is mounted on a vehicle and controls the vehicle speed of the host vehicle to a target vehicle speed, and more particularly to a vehicular travel control device that improves user convenience during follow-up travel.

  2. Description of the Related Art Conventionally, a vehicle travel control device that is mounted on a vehicle and controls the vehicle speed of the host vehicle to a target vehicle speed is known (see, for example, Patent Document 1).

Patent Document 1 states that “one of the purposes is to make constant speed travel (cruise travel) easier and faster”, and “when the brake-off is detected, the vehicle speed at that time is set as the target vehicle speed. "Vehicle and its control method" are disclosed (see the title of the invention and paragraph numbers 0005 and 0012).
JP 2006-281899 A

  It is difficult to apply the prior art described in Patent Document 1 as it is during follow-up running in which the inter-vehicle distance (or inter-vehicle time) with the preceding vehicle is kept substantially constant.

  This is because the brake operation performed by the driver during the follow-up traveling does not necessarily indicate the driver's intention to reduce the target vehicle speed.

  For example, when the driver is forced to step on the brake in response to sudden deceleration of the preceding vehicle during follow-up, it cannot be said that the driver wants to reduce the target vehicle speed.

  As described above, when the conventional technique described in Patent Document 1 is used during follow-up traveling, the target vehicle speed is set to a speed different from the driver's intention, which may impair user convenience. There is a potential problem that it cannot be applied as it is to follow-up running.

  The present invention has been made to solve such problems, and it is a main object of the present invention to provide a vehicular travel control apparatus that improves user convenience during follow-up travel.

  One aspect of the present invention for achieving the above object is a vehicular travel control device that is mounted on a vehicle and controls the vehicle speed of the host vehicle to a target vehicle speed. The first inter-vehicle distance (D1) with the preceding vehicle when the vehicle is depressed (ie when the brake is on) and the preceding vehicle when the brake pedal is released by the operator (ie when the brake is off) The inter-vehicle distance detecting means for detecting the second inter-vehicle distance (D2), and the target when the brake pedal is depressed by the driver and then the driver releases the brake pedal during the follow-up traveling to the preceding vehicle. The target vehicle speed changing means for changing the vehicle speed to the own vehicle speed when the brake pedal is released by the operator, and the second inter-vehicle distance (D2) detected by the inter-vehicle distance detecting means When shorter than the serial first inter-vehicle distance (D1) (D2 <D1), a vehicle control system having a target vehicle speed change inhibiting means for inhibiting a change in the target vehicle speed by the target vehicle speed changing means.

  According to the above aspect, when the inter-vehicle distance with the preceding vehicle when the brake is OFF becomes shorter than the inter-vehicle distance with the preceding vehicle when the brake is ON (in other words, even though the driver steps on the brake pedal) When approaching the preceding vehicle before the brake operation), it is determined that the driver did not want to reduce the target vehicle speed, but that the brake operation was unavoidably performed to prevent approaching the preceding vehicle. Thus, since the target vehicle speed is controlled so as not to decelerate, it is possible to prevent the user's convenience from being impaired by the deceleration of the target vehicle speed not intended by the driver during the follow-up traveling.

  ADVANTAGE OF THE INVENTION According to this invention, the traveling control apparatus for vehicles which improved the user convenience at the time of following driving | running | working can be provided.

  Hereinafter, the best mode for carrying out the present invention will be described with reference to the accompanying drawings. Note that follow-up running control for keeping the inter-vehicle distance (or inter-vehicle time) with the preceding vehicle substantially constant is known to those skilled in the art, and thus detailed description thereof is omitted.

  FIG. 1 is a schematic configuration diagram of a vehicle travel control apparatus 100 according to an embodiment of the present invention.

  The travel control device 100 detects a preceding vehicle that is positioned in front of the host vehicle and traveling in the same direction on the same lane as the host vehicle, and when there is a preceding vehicle, the distance between the host vehicle and the preceding vehicle, and A preceding vehicle detection unit 101 that detects the relative speed of the preceding vehicle is provided. The preceding vehicle detection unit 101 includes, for example, a laser radar sensor, irradiates laser light to a space area in front of the host vehicle, and determines whether there is a preceding vehicle from the time until the reflected light returns and the incident angle. Detect distance and relative speed.

  The travel control device 100 further includes a vehicle speed detection unit 102 that detects the vehicle speed of the host vehicle. In the present embodiment, the vehicle speed detection unit 102 detects the vehicle speed of the host vehicle using, for example, a wheel speed sensor. As an alternative example, when the host vehicle is equipped with a navigation system, the current position information of the host vehicle may be acquired from the navigation system, and the vehicle speed of the host vehicle may be calculated from the change over time.

  The travel control device 100 further includes a brake pedal operation amount detection unit 103 that detects an operation amount (depression amount / stroke amount) of the brake pedal by the driver.

  The travel control device 100 further includes a storage unit 104 that stores and holds a target vehicle speed during follow-up travel, an inter-vehicle distance D1 when the brake is on, and an inter-vehicle distance D2 when the brake is off. In the present embodiment, the storage unit 104 may be an arbitrary storage medium.

  The travel control device 100 further includes an engine control unit 105 that controls the engine output by controlling the throttle valve opening, for example. The engine control unit 105 is, for example, an engine ECU (Electronic Control Unit).

  The travel control device 100 further includes a brake control unit 106 that controls the braking force exerted by the brake system. The brake control unit 106 is, for example, a brake ECU.

  The travel control device 100 further includes a main control unit 107 that performs various calculations described below and comprehensively controls each component of the travel control device 100. The main control unit 107 is, for example, an auto cruise ECU.

  As will be apparent to those skilled in the art, the engine control unit 105, the brake control unit 106, and the main control unit 107 may be realized as one ECU.

  Next, the flow of the target vehicle speed changing process during the follow-up running by the vehicular travel control apparatus 100 according to the present embodiment having such a configuration will be described with reference to the flowchart of FIG. The processing flow shown in FIG. 2 is started when, for example, follow-up running is started, and is ended, for example, when follow-up running is ended.

  First, the main control unit 107 determines whether or not the driver depresses the brake pedal based on the detection result by the brake pedal operation amount detection unit 103, in other words, whether the brake has shifted from the brake-off state to the brake-on state. It is determined whether or not (S201).

  When it is determined that the brake pedal is depressed (brake ON) by the driver (“YES” in S201), the main control unit 107 then obtains the time point obtained from the preceding vehicle detection unit 101 (that is, by the driver). The inter-vehicle distance D1 from the preceding vehicle at the time when the brake pedal is depressed is stored in the storage unit 104 (S202).

  When the inter-vehicle distance D1 when the brake is turned on is stored in this manner, the main control unit 107 then releases the brake pedal by the driver based on the detection result by the brake pedal operation amount detection unit 103 (release). In other words, it is determined whether or not the state has shifted from the brake-on state to the brake-off state (S203).

  When it is determined that the brake pedal has been released (brake OFF) by the driver (“YES” in S203), the main control unit 107 then acquires the time point obtained from the preceding vehicle detection unit 101 (that is, by the driver). The inter-vehicle distance D2 with the preceding vehicle at the time when the brake pedal is released is stored in the storage unit 104 (S204).

  In this way, when it is detected that the driver has released the brake pedal after the brake pedal has been depressed, in other words, the brake is turned off and the brake is turned on, and then the brake is turned on again. When it is detected that the brake has returned to the OFF state, the main control unit 107 determines whether the inter-vehicle distance D1 with the preceding vehicle stored in the storage unit 104 when the brake is ON is greater than the inter-vehicle distance D2 when the brake is OFF It is determined whether or not (S205).

  Whether the determination process in S205 is performed with the intention of decelerating the target vehicle speed in the follow-up by the driver's brake pedal operation including the brake ON detected in S201 and the brake OFF detected in S203, Alternatively, for example, it is a determination process for determining whether the deceleration is performed in order to avoid the approach to the preceding vehicle because the preceding vehicle has suddenly decelerated.

  For example, as shown in FIG. 3, for example, the driver releases the brake pedal at time t2 than the inter-vehicle distance D1 from the host vehicle V1 to the preceding vehicle V2 when the brake pedal is depressed by the driver at time t1. If the inter-vehicle distance D2 is larger (longer), the driver has widened the inter-vehicle distance from the preceding vehicle V2 by operating the brake pedal. It can be interpreted as a deceleration of the target vehicle speed.

  On the other hand, as shown in FIG. 4 as an example, the driver releases the brake pedal at time t2 than the inter-vehicle distance D1 from the host vehicle V1 to the preceding vehicle V2 when the brake pedal is depressed by the driver at time t1. If the inter-vehicle distance D2 is smaller (shorter) when the vehicle is operated, the inter-vehicle distance from the preceding vehicle V2 is approaching even though the driver has operated these brake pedals. The intention of deceleration can be interpreted as deceleration for avoiding approach to the preceding vehicle V2, not deceleration of the target vehicle speed in follow-up traveling.

  In such a case as shown in FIG. 4, if the target vehicle speed in the follow-up running is set to the vehicle speed at the time of brake OFF as in the prior art described above, the preceding vehicle V2 finishes sudden deceleration. When the vehicle starts accelerating again, the target vehicle speed of the host vehicle V1 has been lowered, and there is a possibility that the vehicle will be left without being able to follow up sufficiently. In order to avoid the occurrence of such a situation, it is necessary to increase the target vehicle speed that has been automatically lowered, which is troublesome for the user.

  Returning to FIG. Therefore, in this embodiment, when it is determined that the inter-vehicle distance D2 is shorter than the inter-vehicle distance D1 (“YES” in S205), the main control unit 107 decelerates the target vehicle speed as described with reference to FIG. It is determined that the situation should not be made, and the target vehicle speed at that time is not changed and is held as it is (S206).

  On the other hand, when it is determined that the inter-vehicle distance D2 is equal to or longer than the inter-vehicle distance D1 (“NO” in S205), the main control unit 107 should decelerate the target vehicle speed as described with reference to FIG. The situation is determined to be the situation, and the target vehicle speed at that time is changed to the own vehicle speed when the brake is OFF (in other words, when the inter-vehicle distance D2 is detected) (S207).

  As described above, according to this embodiment, when the brake pedal operation is performed by the driver during the follow-up traveling, it is determined whether or not it is intended to decelerate the target vehicle speed. The target vehicle speed is decelerated only when the driver's intention is determined to be a reduction in the target vehicle speed based on the following vehicle distance and the inter-vehicle distance when the brake is OFF. It is possible to prevent the vehicle speed from decelerating and improve user convenience.

  The present invention is applicable to any vehicle that can perform follow-up traveling control with respect to a preceding vehicle. The power source type, fuel type, appearance design, weight, size, running performance, etc. of the target vehicle are all unquestioned.

1 is a schematic configuration diagram of a vehicle travel control apparatus according to an embodiment of the present invention. It is a flowchart which shows the flow of the target vehicle speed change process in the following driving | running | working by the vehicle travel control apparatus which concerns on one Example of this invention. It is a figure which shows the inter-vehicle distance with a preceding vehicle in case the target vehicle speed in the following driving | running | working is changed by the vehicle travel control apparatus which concerns on one Example of this invention. It is a figure which shows the inter-vehicle distance with a preceding vehicle in case the target vehicle speed in the following driving | running | working is not changed by the vehicle travel control apparatus which concerns on one Example of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Vehicle travel control apparatus 101 Leading vehicle detection part 102 Vehicle speed detection part 103 Brake pedal operation amount detection part 104 Storage part 105 Engine control part 106 Brake control part 107 Main control part

Claims (1)

A vehicle travel control device that is mounted on a vehicle and controls the vehicle speed of the host vehicle to a target vehicle speed,
During follow-up to the preceding vehicle, the first inter-vehicle distance from the preceding vehicle when the driver depresses the brake pedal, and the second inter-vehicle distance from the preceding vehicle when the driver releases the brake pedal An inter-vehicle distance detecting means for detecting
When the brake pedal is depressed by the driver and the driver releases the brake pedal while following the preceding vehicle, the target vehicle speed is changed to the own vehicle vehicle speed when the brake pedal is released by the operator. A target vehicle speed changing means to be changed;
Target vehicle speed change prohibiting means for prohibiting the change of the target vehicle speed by the target vehicle speed changing means when the second inter-vehicle distance detected by the inter-vehicle distance detecting means is shorter than the first inter-vehicle distance;
A vehicle travel control device comprising:

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