METHOD FOR CHANGING A FORWARD DISPLACEMENT OF AN OCCUPANT OF A VEHICLE DURING BRAKING OF THE VEHICLE AND CONTROL UNIT

Abstract

The invention relates to a method for changing a forward displacement (104) of an occupant (106) of a vehicle (100) during braking of the vehicle (100). Initially, a seat belt status signal (112) which represents a status of a seat belt (108) for buckling in the occupant (106), and an occupant position signal which represents a position and/or location of the occupant (106) in the vehicle (100) and/or a change in the position and/or the location are read in. The two signals are processed to ascertain the forward displacement (104). Finally, at least one control signal (120, 121, 138) for controlling a braking device (122) of the vehicle (100) and/or at least one restraint means (108, 132) for restraining the occupant (106) is/are generated as a function of the forward displacement (104) in order to alter the forward displacement (104).

Claims

1.-11. (canceled)

12. A method for changing a forward displacement of an occupant of a vehicle during a braking of the vehicle, comprising: reading in a seat belt status signal that represents a status of a seat belt for buckling in the occupant, and an occupant position signal that represents at least one of: at least one of a position and a location of the occupant in the vehicle, and a change in the at least one of the position and the location; processing the seat belt status signal and the occupant position signal to ascertain the forward displacement; and generating at least one control signal for controlling at least one of a braking device of the vehicle and at least one restraint device for restraining the occupant as a function of the forward displacement in order to alter the forward displacement.

13. The method as recited in claim 12, wherein: in the step of processing, a distance of the occupant from at least one of a steering wheel, a dashboard, and a backrest of the vehicle representing the forward displacement is determined on the basis of at least one of the seat belt status signal and the occupant position signal, wherein the control signal is generated as a function of the distance.

14. The method as recited in claim 12, wherein: in the step of reading in, a signal that represents at least one of a resilience of the seat belt, a state of a buckle, a state of a seat belt retractor, and a state of a seat belt tensioner of the seat belt is read in as the seat belt status signal.

15. The method as recited in claim 12, wherein: in the step of reading in, a signal is read in as the occupant position signal that is generated by at least one of: a passenger compartment detection device for detecting a passenger compartment of the vehicle, and a seat occupancy identification device for identifying a seat occupancy in the vehicle.

16. The method as recited in claim 12, wherein: in the step of reading in, a signal is read in as the occupant position signal that represents at least one of: an inclination of at least one of a backrest and a seat cushion of a seat occupied by the occupant, and a position of the seat in a longitudinal direction of the vehicle.

17. The method as recited in claim 12, wherein: in the step of reading in, at least one of a surroundings sensor signal that represents a signal generated by at least one surroundings sensor of the vehicle and a brake signal that represents a signal generated by the braking device is read in, in the step of processing, at least one of the surroundings sensor signal and the brake signal is processed to ascertain an impending collision of the vehicle, and in the step of generating, the control signal is generated as a function of a result of the processing of at least one of the surroundings sensor signal and the brake signal.

18. The method as recited in claim 12, wherein: in the step of reading in, a piece of occupant information that represents at least one of a weight, a height, a gender, and an age of the occupant is read in, and in the step of generating, the control signal is generated based on the piece of occupant information.

19. The method as recited in claim 12, wherein: in the step of generating, the control signal is generated to restrain the occupant with the aid of the restraint device, utilizing a path covered by the occupant during the forward displacement.

20. A control unit for carrying out a method for changing a forward displacement of an occupant of a vehicle during a braking of the vehicle, the method comprising: reading in a seat belt status signal that represents a status of a seat belt for buckling in the occupant, and an occupant position signal that represents at least one of: at least one of a position and a location of the occupant in the vehicle, and a change in the at least one of the position and the location; processing the seat belt status signal and the occupant position signal to ascertain the forward displacement; and generating at least one control signal for controlling at least one of a braking device of the vehicle and at least one restraint device for restraining the occupant as a function of the forward displacement in order to alter the forward displacement.

21. A computer program for carrying out a method for changing a forward displacement of an occupant of a vehicle during a braking of the vehicle, the method comprising: reading in a seat belt status signal that represents a status of a seat belt for buckling in the occupant, and an occupant position signal that represents at least one of: at least one of a position and a location of the occupant in the vehicle, and a change in the at least one of the position and the location; processing the seat belt status signal and the occupant position signal to ascertain the forward displacement; and generating at least one control signal for controlling at least one of a braking device of the vehicle and at least one restraint device for restraining the occupant as a function of the forward displacement in order to alter the forward displacement.

22. A machine-readable storage medium on which a computer program is stored, wherein the computer program is for carrying out a method for changing a forward displacement of an occupant of a vehicle during a braking of the vehicle, the method comprising: reading in a seat belt status signal that represents a status of a seat belt for buckling in the occupant, and an occupant position signal that represents at least one of: at least one of a position and a location of the occupant in the vehicle, and a change in the at least one of the position and the location; processing the seat belt status signal and the occupant position signal to ascertain the forward displacement; and generating at least one control signal for controlling at least one of a braking device of the vehicle and at least one restraint device for restraining the occupant as a function of the forward displacement in order to alter the forward displacement.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0022] FIG. 1 shows a schematic representation of a vehicle including a control unit according to one exemplary embodiment.

[0023] FIG. 2 shows a schematic representation of a control unit according to one exemplary embodiment.

[0024] FIG. 3 shows a schematic representation of a control unit according to one exemplary embodiment.

[0025] FIG. 4 shows a schematic representation of a strategy for activating a braking profile using a control unit according to one exemplary embodiment.

[0026] FIG. 5 shows a schematic representation of a time curve of a deceleration, of a belt force and of an occupant displacement during braking of a vehicle with the aid of a control unit according to one exemplary embodiment.

[0027] FIG. 6 shows a schematic representation of a time curve of a deceleration, of a belt force and of an occupant displacement during braking of a vehicle with the aid of a control unit according to one exemplary embodiment.

[0028] FIG. 7 shows a schematic representation of a time curve of a deceleration, of a belt force and of an occupant displacement during braking of a vehicle with the aid of a control unit according to one exemplary embodiment.

[0029] FIG. 8 shows a flow chart of a method according to one exemplary embodiment.

DETAILED DESCRIPTION

[0030] In the following description of favorable exemplary embodiments of the present invention, identical or similar reference numerals are used for similarly acting elements shown in the different figures, and a repeated description of these elements is dispensed with.

[0031] FIG. 1 shows a schematic representation of a vehicle 100 including a control unit 102 according to one exemplary embodiment. Control unit 102 is designed to alter a forward displacement 104 of an occupant 106 of vehicle 100, which here is a driver, during braking of vehicle 100. For this purpose, control unit 102 receives a seat belt status signal 112 which represents a status of seat belt 108 from a seat belt 108, with the aid of which occupant 106 is buckled to a seat 110 of vehicle 100. For example, seat belt status signal 112 according to FIG. 1 indicates that a buckle of seat belt 108 is in a closed state. Seat belt status signal 112 may furthermore represent a resilience of seat belt 108 and a status of a seat belt retractor or of an electric or pyrotechnic seat belt tensioner of seat belt 108. For detecting and transmitting seat belt status signal 112, seat belt 108 according to FIG. 1 includes a seat belt control unit 114. Depending on the exemplary embodiment, seat belt control unit 114 may be designed to control the buckle, the seat belt retractor or the seat belt tensioner, for example to alter the resilience or a slack of seat belt 106. The buckle, the seat belt retractor or the seat belt tensioner may be implemented as part of seat belt control unit 114.

[0032] Vehicle 100 furthermore includes a passenger compartment detection device 116, implemented as a camera here, which is designed to detect occupant 106 in the passenger compartment of vehicle 100, and to transmit a detection signal 118 representing occupant 106 to control unit 102. Control unit 102 is designed to ascertain a position or location of occupant 106 in vehicle 100, or also a change in the position or location over time, using detection signal 118. Furthermore, control unit 102 is designed to ascertain forward displacement 104, using seat belt status signal 112 and as a function of the position or location of occupant 106.

[0033] Depending on a thus ascertained value of forward displacement 104, control unit 102 according to FIG. 1 generates a first control signal 120 and a second control signal 121. First control signal 120 is used to control a braking device 122 of vehicle 100, and second control signal 121 is used to control a restraint means, which is the seat belt tensioner integrated into seat belt 108 here. Braking device 122 is designed to control a brake force for braking vehicle 100, using first control signal 120. For example, braking device 122 controls the brake force in such a way that forward displacement 104 during braking of vehicle 100 is reduced. Analogously, seat belt control unit 114 is designed to control the resilience of seat belt 108 with the aid of the seat belt tensioner, using second control signal 121, in such a way that forward displacement 104 during braking of vehicle 100 is also reduced.

[0034] According to the exemplary embodiment shown in FIG. 1, control unit 102 is designed to ascertain a distance 124 between occupant 106 and a steering wheel 125 of vehicle 100 representing forward displacement 104, using detection signal 118. Accordingly, control unit 102 generates control signals 120, 121 as a function of distance 124.

[0035] Optionally, vehicle 100 is equipped with a seat occupancy identification device 126, which is a weight sensor integrated into a seat cushion 128 here. Seat occupancy identification device 126 is designed to identify an occupancy of seat 110 by occupant 106 and to transmit an occupancy signal 130 representing the occupancy to control unit 102. Control unit 102 is designed to ascertain the position or location of occupant 106, in addition or as an alternative to the use of detection signal 118, using occupancy signal 130.

[0036] According to one further exemplary embodiment, seat 110 is adjustable with the aid of an optional seat adjustment device 132. Seat adjustment device 132 is designed to alter an inclination of a backrest 134 of seat 110 and of seat cushion 128, and a seat position of seat 110 in the longitudinal direction of vehicle 100. Possible adjustment directions of seat 110 are identified by way of example by three arrows. Seat adjustment device 132 is furthermore designed to detect the inclination of backrest 134 and of seat cushion 128 and the seat position, and to transmit an adjustment signal 136 representing the inclination and the seat position to control unit 102. Control unit 102 is designed to ascertain the position or location of occupant 106 using adjustment signal 136.

[0037] Optionally, control unit 102 is designed to generate a third control signal 138 as a function of the ascertained forward displacement 104, and to transmit it to seat adjustment device 132. Seat adjustment device 132 is designed to control the inclination of backrest 134 or of seat cushion 128, or the seat position, using third control signal 138. Seat adjustment device 132 thus also functions as a restraint means to alter forward displacement 104 of occupant 106.

[0038] According to one further exemplary embodiment, braking device 122 is designed to transmit a brake signal 140, which represents the brake force for example, to control unit 102. Vehicle 100 includes an optional surroundings sensor 142, which is designed to detect surroundings of vehicle 100 and to transmit a surroundings sensor signal 144 representing the surroundings to control unit 102. Control unit 102 is designed to ascertain an impending collision of vehicle 100 with an obstacle 146, which is a further vehicle preceding vehicle 100 here, using brake signal 140 and surroundings sensor signal 144, and to generate control signals 120, 121, 138 as a function of an evaluation of the two signals 140, 144 in this regard.

[0039] The vehicle surroundings are monitored, for example, by at least one surroundings detection system with the aid of radar, LIDAR or video. An impending collision with an object in the surroundings may be identified by control unit 102 with the aid of corresponding surroundings data of the surroundings detection system. Control unit 102 may be designed to evaluate an avoidability of the collision by steering or brake interventions.

[0040] The position of the occupant is monitored with the aid of a passenger compartment detection system, for example. If the occupant is situated in a critical position, i.e., within the keep-out zone, this is identified by an algorithm in control unit 102, and the information is forwarded. The keep-out zone may be described by a distance of the occupant from the steering wheel, the distance being selected smaller than 10 cm, for example.

[0041] A braking deceleration curve of vehicle 100 may additionally be determined using personal information such as weight, height, gender and age, as is described in greater detail hereafter.

[0042] If a braking deceleration initiated by the occupant is not sufficient to avoid a collision of the vehicle, optimal braking assistance may be ascertained with the aid of control unit 102.

[0043] FIG. 2 shows a schematic representation of a control unit 102 according to one exemplary embodiment. Control unit 102 is a control unit described above based on FIG. 1, for example. Control unit 102 includes a read-in unit 210 for reading in seat belt status signal 112 and an occupant position signal 212 which represents the position or location of the occupant or the change in the position or location of the occupant. Occupant position signal 212 is a signal, for example, which was generated based on detection signal 118, occupancy signal 130 or adjustment signal 136 by a linking unit 214 connected to read-in unit 210, and was forwarded to read-in unit 210. Linking unit 214 may be implemented as a component of read-in unit 210.

[0044] A processing unit 220 is designed to receive seat belt status signal 112 and occupant position signal 212 from read-in unit 210, to ascertain a forward displacement value 222 representing the forward displacement, using the two signals 112, 212, and to transmit it to a generating unit 230. Generating unit 230 is designed to generate control signals 120, 121, 138, using forward displacement value 222.

[0045] According to one optional exemplary embodiment, read-in unit 210 is designed to additionally read in brake signal 140 and surroundings sensor signal 144 and to forward them to processing unit 220. Processing unit 220 is designed to ascertain at least one collision parameter 232 representing the impending collision of the vehicle, for example an impact point in time, an impact location or an impact speed, using the two signals 140, 144, and to transmit it to generating unit 230. Generating unit 230 is designed to furthermore generate control signals 120, 121, 138 taking collision parameter 232 into consideration.

[0046] Optionally, read-in unit 210 is designed to read in a piece of occupant information 234, which depending on the exemplary embodiment represents a weight, a height, a gender or an age of the occupant, and to forward it to the generating unit 230. Generating unit 230 is designed to generate control signals 120, 121, 138 using piece of occupant information 234.

[0047] FIG. 3 shows a schematic representation of a control unit 102 according to one exemplary embodiment, for example a control unit as described above based on FIGS. 1 and 2. Control unit 102 is connected to a surroundings detection system, which includes surroundings sensor 142, a passenger compartment detection system, which includes passenger compartment detection device 116, seat occupancy identification device 126, seat adjustment device 132, for example an electric seat adjuster, an electric seat belt tensioner 300 or a pyrotechnic seat belt tensioner 302, which may each form part of the seat belt, and a braking system, which includes braking device 122.

[0048] FIG. 4 shows a schematic representation of a strategy for activating a braking profile using a control unit according to one exemplary embodiment, for example a control unit described above based on FIGS. 1 through 3. In a step 410, it is checked whether the occupant is buckled up. If it is established in step 410 that the occupant is not buckled up, a first braking profile for braking the vehicle is activated in a step 420. If, in contrast, it is established in step 410 that the occupant is buckled up, it is checked in a step 430 whether an electric seat belt tensioner is available. If it is established in step 430 that such a seat belt tensioner is not available, a corresponding second braking profile is activated in a step 440. Otherwise, a corresponding third braking profile is activated in a step 450. In response to the activation of the third braking profile, it is checked in a step 460 whether the occupant is situated in the so-called keep-out zone. For example, the occupant is situated in the keep-out zone if the distance between the occupant and the steering wheel drops below a predefined threshold value. If it is established in step 460 that the occupant is situated in the keep-out zone, a corresponding fourth braking profile is activated in a step 470. Otherwise, the third braking profile is activated. In response to the activation of the fourth braking profile, step 460 is repeated at least one more time to enable continuous monitoring of the keep-out zone.

[0049] FIG. 5 shows a schematic representation of a time curve of a deceleration 500, of a belt force 502 and of an occupant displacement 504 during braking of a vehicle with the aid of a control unit according to one exemplary embodiment, for example a control unit as described above based on FIGS. 1 through 4. Shown is a braking profile for a buckled-up occupant without electric seat belt tensioner, the individual curves being represented beneath one another. The curves are divided into three chronologically consecutive sections 510, 512, 514, a first section 510 representing an increased criticality, a second section 512 representing a high criticality, and a third section 514 representing an ultrahigh criticality. A fourth section 516 represents a collision of the vehicle.

[0050] In first section 510, a non-critical braking jolt takes place, which manifests itself in a steep rise in deceleration 500 and belt force 502 at the beginning of first section 510. Slack of the seat belt may be reduced via the braking jolt. The braking jolt is marked with two arrows in FIG. 5. Subsequent to the braking jolt, a slight deceleration takes place, which maintains the occupant/seat belt coupling, represented by a consistently low deceleration in first section 510.

[0051] A partial brake application takes place in second section 512. The deceleration increases suddenly. The belt force shows a slight increase. Toward the end of second section 512, a moderate forward displacement takes place, which is apparent from a slight increase in the occupant displacement.

[0052] In third section 514, the deceleration again increases suddenly. The belt force initially remains constant. Toward the end of third section 514, a pyrotechnic seat belt tensioner is pre-triggered, so that the belt force suddenly increases briefly and remains at a significantly higher level than before the seat belt tensioner was ignited. During the ignition of the pyrotechnic seat belt tensioner, the occupant displacement drops steeply, for example to zero, and the occupant experiences a velocity V.sub.precrash counter to the crash direction.

[0053] The moderate forward displacement in sections 500, 512, 514 preceding the collision may be used by a deploying restraint means to condition the occupant in such a way that a velocity V.sub.precrash and a velocity V.sub.crash destructively superimpose.

[0054] FIG. 6 shows a schematic representation of a time curve of a deceleration 500, of a belt force 502 and of an occupant displacement 504 during braking of a vehicle with the aid of a control unit according to one exemplary embodiment. In contrast to FIG. 5, FIG. 6 shows a braking profile for a buckled-up occupant with an available electric seat belt tensioner. In first section 510, a slight tensioning of the seat belt via the electric seat belt tensioner takes place in order to block it. This results in an earlier coupling. In second section 512, a partial brake application takes place, focusing on collision avoidance or energy reduction. The point in time and magnitude of the deceleration are dependent on the belt force. In third section 514, a full brake application takes place at approximately 1 g. The pyrotechnic seat belt tensioner is pre-triggered to have a deploying system. The space toward the rear may be utilized to build up speed unbraked. After ignition of the pyrotechnic seat belt tensioner, the seat belt tensioner may be by a further device (pyrotechnic, electric, mechanical and/or pneumatic) to obtain a coupling. With the aid of the deploying system, the forward displacement may thus be reduced.

[0055] According to a further exemplary embodiment, an active seat adjuster may be used to support a deploying effect.

[0056] FIG. 7 shows a schematic representation of a time curve of a deceleration 500, of a belt force 502 and of an occupant displacement 504 during braking of a vehicle with the aid of a control unit according to one exemplary embodiment. In contrast to FIGS. 5 and 6, FIG. 7 shows a braking profile for an occupant situated in the keep-out zone, also known as the KO zone.

[0057] In second section 512, the occupant is pulled back by lowering the deceleration to reduce the force acting on the occupant and pull him or her out of the KO zone with the aid of the electric seat belt tensioner. The occupant is situated in the KO zone when the distance of the occupant from the steering wheel or from the dashboard is less than 10 cm, for example. The KO zone is shown schematically in FIG. 7 in a separate diagram as distance a between a y axis of the diagram and a dotted line. The y axis represents a force F, and an x axis represents a length s, where

[00001]$\stackrel{\_}{F}=\frac{1}{2}.Math.\frac{{\mathrm{mv}}^2}{s},$

applies.

[0058] As soon as it is identified that the occupant is situated in the KO zone, the braking profile is started. As soon as the occupant is situated outside the KO zone, the braking profile is terminated and, for example, a higher-level braking profile is adopted. The advantage of the braking profile shown in FIG. 7 is that the occupant may be moved out of the KO zone by displacement.

[0059] Depending on the exemplary embodiment, with the determination of the braking profiles described based on FIGS. 5 through 7 during an impending collision, the displacement of the occupant may be minimized, taking into consideration a present seat belt status (fastened, retractor blocked, present resilience, resilience already applied in the present fastening cycle), a use of the forward displacement as a rearward displacement path by pre-triggering of the pyrotechnic seat belt tensioner, a present seat setting (backrest inclination, seat longitudinal adjustment, seat cushion inclination) and personal information, such as weight, height, gender or age.

[0060] FIG. 8 shows a flow chart of a method 800 according to one exemplary embodiment. Method 800 may be carried out or activated in conjunction with a control unit described above based on FIGS. 1 through 7, for example. In a step 810, the seat belt status signal and the occupant position signal are read in. In a step 820, the two signals are processed to ascertain the forward displacement of the occupant. Finally, in a step 830, the control signal for controlling the braking device or the restraint means of the vehicle is generated as a function of the forward displacement in order to alter the forward displacement.

[0061] Steps 810, 820, 830 may be carried out continuously.

[0062] For example, method 800 is cyclically invoked during an impending collision of the vehicle, the activation of the electric seat belt tensioner or of the electric seat adjuster being continuously taken into consideration.

[0063] Additionally, by igniting the pyrotechnic seat belt tensioner before the collision, a deploying protective system is created, which utilizes the forward displacement of the occupant caused by the vehicle deceleration as a back displacement path.

[0064] By creating the back displacement path in the braking profile through the vehicle deceleration and eliminating the slack of the seat belt, the effectiveness of the system may be increased.

[0065] If one exemplary embodiment includes an and/or linkage between a first feature and a second feature, this should be read in such a way that the exemplary embodiment according to one specific embodiment includes both the first feature and the second feature, and according to an additional specific embodiment includes either only the first feature or only the second feature.