Method for determining a reaction time of a driver of a vehicle for actuating a brake pedal and corresponding assistance system and vehicle

Abstract

Method for determining a reaction time of a driver of a vehicle (10) for actuating a brake pedal (4) of the vehicle (10) in order to thereby support an assistance system (20) of the vehicle (10), whereby the driver's current readiness to operate the brake pedal (4) is automatically detected, wherein the reaction time is automatically determined as a function of the readiness, wherein a pressure on an accelerator pedal (5) of the vehicle (10) and a position of the accelerator pedal (5) are automatically detected, wherein the reaction time is determined automatically as a function of the pressure and position of the accelerator pedal (5), wherein a curve of the pressure exerted on the accelerator pedal (5) is recorded, where the reaction time is determined depending on the course, and wherein, depending on the reaction time, a warning of a collision is generated or a driving behavior of the vehicle (10) is intervened in.

Description

[0001] The present invention relates to a method for determining a reaction time of a vehicle driver with which this driver will actuate a brake pedal of the vehicle. Furthermore, the present invention relates to a correspondingly configured assistance system and a correspondingly configured vehicle.

[0002] DE 10 2008 019 519 A1 describes a method for determining a safety distance, taking into account a determined individual reaction time of the respective driver.

[0003] In DE 100 39 795 A1, warnings are issued to a driver depending on the driver’s attention.

[0004] DE 101 48 534 A1 relates to a method for detecting a driver’s readiness to brake in order to generate adaptive warning signals.

[0005] DE 198 03 870 A1 relates to a method and a device for braking vehicles.

[0006] DE 10 2008 043 220 A1 relates to a control device for automatically guiding a vehicle, in particular during a parking maneuver, with an interface to a monitoring unit of a brake control device of the vehicle for determining a driver's readiness to brake, such that automatic guidance of the vehicle is interrupted if a driver's readiness to brake is not determined.

[0007] The present invention has for its object to determine the reaction time of a driver for actuating a brake pedal of the vehicle more accurately than is known from the prior art in order to support an assistance system of the vehicle by means of the reaction time determined in this way.

[0008] According to the invention, this object is achieved by a method for determining a reaction time of a driver of a vehicle for actuating a brake pedal of the vehicle according to claim 1, by an assistance system according to claim 7, and by a vehicle according to claim 9. The dependent claims define preferred and advantageous embodiments of the present invention.

[0009] Within the scope of the present invention, a method is provided for determining a reaction time of a driver of a vehicle, wherein the driver's reaction time determines a time in which the driver could currently (i.e., at the time the determination is made) depress a brake pedal of the vehicle. Determining this reaction time supports the functioning of an assistance system of the vehicle. To determine the reaction time, the driver's current readiness to depress the brake pedal is automatically detected. The reaction time is then determined depending on this detected readiness.

[0010] While the prior art determines a general reaction time or the driver's general attention, the present invention determines or records a specific reaction time related to the actuation of the brake pedal. In other words, the prior art determines the general reaction time, which predicts a period of time in which the driver will react to an unforeseen event with some (unspecified) reaction or action. The reaction time (or attention) recorded in the prior art is therefore not specifically related to a particular action, as is the case with the present invention with regard to the actuation of the brake pedal.

[0011] Since the reaction time determined according to the invention is directed only at the actuation of the brake pedal, this reaction time can advantageously be determined much more accurately than is the case with the prior art. For example, it would be conceivable that the prior art determines a general reaction time of 0.6 s for an attentive driver, while the present invention determines a reaction time of 0.3 s for the actuation of the brake pedal by the same driver at the same time, since, for example, the invention detects that the driver is about to actuate the brake pedal (because, for example, their foot is already on the brake pedal).

[0012] According to the invention, the position of the driver's brake foot relative to the brake pedal can be detected in order to determine the reaction time based on this position of the brake foot. The brake foot is understood to be the foot with which the driver normally operates the brake pedal. This is usually the driver's right foot. The position of the brake foot relative to the brake pedal can be detected, for example, by a camera, other optical sensors, or other sensors in the vehicle's footwell.

[0013] If the brake foot is detected near the brake pedal (e.g. on the brake pedal), in most cases a shorter reaction time is determined than if the brake foot is, for example, on the accelerator pedal of the vehicle.

[0014] For this purpose, for example, a pressure on the vehicle's accelerator pedal and / or a position of the accelerator pedal can be automatically detected, whereby the reaction time is then determined depending on the pressure detected in this way and / or the position of the accelerator pedal detected in this way.

[0015] If a position other than the initial position of the accelerator pedal is detected, the normal driver's foot will depress the accelerator pedal. To depress the brake pedal, the brake foot must first be removed from the accelerator pedal and then placed on the brake pedal, resulting in an increased reaction time (until the vehicle brakes). The initial position of the accelerator pedal is defined as a position of the accelerator pedal in which no force is exerted on the accelerator pedal.

[0016] Even when the accelerator pedal is in its home position, the brake foot may be on the accelerator pedal. In this case, a pressure on the accelerator pedal or a touch of the accelerator pedal is detected, but this pressure is not sufficient to move the accelerator pedal from its home position. In this case, too, the brake foot must first leave the accelerator pedal before being guided onto the brake pedal to depress the brake pedal, which in turn increases the reaction time.

[0017] If the pressure applied to the accelerator pedal by the brake foot detects a reduction in this pressure, or if the position of the accelerator pedal changes toward its original position, this can be interpreted as the driver removing their foot from the accelerator pedal and subsequently depressing the brake pedal, resulting in a short reaction time within the meaning of the present invention. In other words, the reaction time can also be determined depending on the pressure applied to the brake pedal or depending on a change in the position of the accelerator pedal.

[0018] Furthermore, within the scope of the present invention, a pressure on the brake pedal and / or a position of the brake pedal can be detected. The reaction time is determined depending on this pressure and / or the position of the brake pedal.

[0019] If a position other than the initial position of the brake pedal is detected, the driver is already on the brake, so the reaction time for (further) actuation of the brake pedal will be extremely short. As with the accelerator pedal, the brake pedal may also be in its initial position, but the brake foot is still touching the brake pedal, which is detected by detecting pressure on the brake pedal or by detecting contact with the brake pedal. In this case, too, the driver is essentially standing on the brake pedal, so the reaction time for actuating the brake pedal is very short.

[0020] According to a preferred embodiment of the invention, the assistance system is a collision warning system which warns the driver of the vehicle of a collision of his vehicle with an obstacle (e.g. another vehicle driving in front of the vehicle or a stationary object).

[0021] Collision warning systems are designed to warn the driver of impending rear-end collisions. These collision warning systems exhibit the greatest potential in situations where the driver is inattentive at the crucial moment (when a collision is imminent) and does not recognize the danger of a rear-end collision. State-of-the-art collision warning systems either make a fixed assumption regarding the driver's reaction time or measure a general reaction time, as described above. However, if the driver has already recognized the risk of a collision and has already moved their foot toward the brake pedal, the reaction time determined by the state-of-the-art is not appropriate.In these cases, in which the driver has already moved their brake foot towards the brake pedal, the reaction time (time elapsed until the brake pedal is depressed) is significantly shorter than determined according to the prior art, as a result of which the prior art collision warning systems issue a collision warning too early, which the driver perceives as unnecessary and annoying. In contrast, the present invention aims to observe the brake foot in order to determine the reaction time depending on the driver's current driving behavior (i.e., to reduce it when the brake foot is already on the brake pedal). This either avoids a warning or issues it at a time that is acceptable to the driver.

[0022] According to the invention, other types of assistance systems can also be supported. For example, the activation of a brake assist system, which automatically brakes the vehicle to avoid a collision, can be configured depending on the reaction time determined according to the invention.

[0023] Within the scope of the present invention, an assistance system for a vehicle is also provided. The assistance system comprises a controller and at least one sensor. The assistance system is designed to generate an indication (e.g., a warning of a collision) or to intervene in the driving behavior of the vehicle (e.g., to brake the vehicle) depending on a reaction time of a driver of the vehicle. The reaction time determines a time in which the driver of the vehicle can or will actuate a brake pedal of the vehicle. By means of the at least one sensor, the assistance system detects the current willingness of the driver to actuate the brake pedal. The assistance system determines the reaction time depending on this readiness detected in this way.

[0024] The advantages of the assistance system according to the invention essentially correspond to the advantages of the method according to the invention, so that a repetition is omitted here.

[0025] Finally, within the scope of the present invention, a vehicle is provided which comprises an assistance system according to the invention.

[0026] With the present invention, the reaction time within which a vehicle driver can apply the brake pedal in an emergency can be determined more accurately than is the case with the prior art. This advantageously allows, for example, a driver warning to be adapted to the driver's current behavior, thus reducing the likelihood of unnecessary and thus disruptive warnings being generated.

[0027] The present invention is particularly suitable for motor vehicles equipped with an assistance system. Of course, the present invention is not limited to this preferred area of ​​application, as the present invention can also be used, for example, in ships, aircraft, or track-bound or rail-guided vehicles.

[0028] In the following, the present invention is explained in detail using embodiments of the invention with reference to the single figure.

[0029] The single figure schematically shows a vehicle according to the invention with an assistance system according to the invention.

[0030] The single figure schematically shows a vehicle 10 according to the invention, which comprises an assistance system 20 according to the invention, a brake pedal 4 and an accelerator pedal 5. The assistance system 20 in turn comprises a controller 3, a first pressure sensor 1, a second pressure sensor 2 and a loudspeaker 6. The first pressure sensor 1 measures a pressure, usually exerted by a foot, on the accelerator pedal 5 of the vehicle 10. The second pressure sensor 2 measures a pressure, also usually exerted by a foot, on the brake pedal 4 of the vehicle 10. Depending on the pressure detected by the first pressure sensor 1 and the pressure detected by the second pressure sensor 2, the controller 3 determines a reaction time of the driver. This reaction time indicates the time in which the driver reacts to a specific event (e.g., the brake lights of the vehicle ahead illuminating) by actuating the brake pedal 5.Depending on this reaction time determined in this way and depending on other variables (e.g. speed of the vehicle 10 and distance from the vehicle driving in front), the assistance system 20 issues a warning of an impending collision via the loudspeaker 6.

Claims

[1] Method for determining a reaction time of a driver of a vehicle (10) for actuating a brake pedal (4) of the vehicle (10) in order to thereby support an assistance system (20) of the vehicle (10), whereby the driver's current readiness to operate the brake pedal (4) is automatically detected, wherein the reaction time is automatically determined as a function of the readiness, wherein a pressure on an accelerator pedal (5) of the vehicle (10) and a position of the accelerator pedal (5) are automatically detected, wherein the reaction time is determined automatically as a function of the pressure and position of the accelerator pedal (5), wherein a curve of the pressure exerted on the accelerator pedal (5) is recorded, where the reaction time is determined depending on the course, and wherein, depending on the reaction time, a warning of a collision is generated or a driving behavior of the vehicle (10) is intervened in. [2] Method according to claim 1, characterized by that a change in the position of the accelerator pedal is detected and that the reaction time is determined depending on the course. [3] Method according to one of the preceding claims, characterized by , that a position of a brake foot of the driver with respect to the brake pedal (4) is automatically detected, wherein the driver actuates the brake pedal (4) with the brake foot, and that the reaction time is automatically determined depending on the position of the brake foot. [4] Method according to claim 3, characterized by that the position of the driver's brake foot relative to the brake pedal (4) is detected by means of a camera or by means of at least one optical sensor. [5] Method according to one of the preceding claims, characterized by , that a pressure on the brake pedal (4) and / or a position of the brake pedal (4) is automatically detected, and that the reaction time is determined automatically as a function of the pressure and / or the position of the brake pedal (4). [6] Method according to one of the preceding claims, characterized by that the assistance system (20) is a collision warning system (20) with which the driver is warned of a collision of the vehicle (10) with an obstacle. [7] Assistance system (20) for a vehicle (10), wherein the assistance system (20) comprises a controller (3) and a sensor (1; 2), wherein the assistance system (20) is designed to generate an indication or to intervene in a driving behavior of the vehicle (10) depending on a reaction time of a driver of the vehicle (10) for actuating a brake pedal (4) of the vehicle (10), and wherein the assistance system (20) is designed such that the assistance system (20) detects by means of the sensor (1) a current readiness of the driver to actuate the brake pedal (4), and that the assistance system (20) determines the reaction time depending on the readiness, wherein the assistance system (20) is designed to detect a pressure on an accelerator pedal (5) of the vehicle (10) and a position of the accelerator pedal (5), to determine the reaction time as a function of the pressure and position of the accelerator pedal (5), to record a curve of the pressure exerted on the accelerator pedal (5), to determine the reaction time depending on the course, and to generate a warning of a collision or to intervene in the driving behavior of the vehicle (10) depending on the reaction time. [8] Assistance system (20) according to claim 7, characterized bythat the assistance system (20) is designed to carry out the method according to one of claims 1-6. [9] Vehicle (10) with an assistance system (20) according to claim 7 or 8.

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