Seat belt system and method for controlling a seat belt system for a vehicle with at least one autonomous driving function

Abstract

Seat belt device (1) for a vehicle with at least one autonomous driving function with at least -a first webbing section (2) wherein -the first belt section (2) is formed by a 3-point belt with a diagonal belt section (6) crossing the occupant's chest and a pelvic belt section (7) crossing the occupant's pelvis, characterized in that -at least one signaling device (4) is provided which can be activated to issue a signal requesting the occupant to remove or fasten the first belt section (2) when at least one of the autonomous driving functions is activated or deactivated, or when a signal is transmitted from an external traffic control device (17), traffic monitoring device or road monitoring device, or when a predefined driving condition exists, wherein -the diagonal belt section (6) can be released depending on the activation of an autonomous driving function and / or depending on the presence of a predefined driving condition.

Description

[0001] The present invention relates to a safety belt device having the features of the preamble of claim 1 and a method for controlling a safety belt device for an at least partially autonomously driving vehicle having the features of the preamble of claim 4.

[0002] Restraint systems in vehicles generally include airbags in various configurations and geometries, which, when activated, cover different areas of the vehicle's interior structure and are intended to at least reduce the likelihood of serious injury to the occupant upon impact with the interior structure. Furthermore, the restraint systems include additional safety belt devices with various belt webbing sections that, when fastened, restrain the occupant, along with associated belt retractors with a locking mechanism, which are permanently attached to the vehicle, onto which the belt webbing can be wound, and belt buckles that are permanently attached to the vehicle. The belt webbing can be wound onto the belt retractors at one end and secured to the vehicle with their free ends via an end fitting.The purpose of safety belt devices is to limit the movements of the occupant and, in particular, to limit and control forward displacement; for this purpose, the belt retractors, buckles or end fittings may incorporate additional force-limiting devices and / or irreversible or reversible belt pretensioners.

[0003] In practice, safety belt devices with a belt strap on which a belt tongue is slidably guided, which can be locked in a belt buckle fixed to the vehicle and which, in the locked position, divides the belt strap into a diagonal belt section and a lap belt section to form a 3-point belt, have proven to be the preferred option.

[0004] Furthermore, there are efforts to relieve the driver of various tasks while driving in order to increase driving comfort. In addition to various sensors and control units, additional actuators can be provided to control the steering, brakes, and fuel supply, so that the vehicle can perform certain functions, such as steering, braking, or accelerating, autonomously. Vehicles with such automated driving systems are also referred to as semi-autonomous or fully autonomous vehicles, depending on the scope of the functions assumed. Because the vehicle assumes these functions, the driver can choose to attend to another activity or even rest while driving. In any case, the driver does not have to devote as much attention to driving as they previously had to when driving the vehicle themselves.A disadvantage of this is that the driver can only fully benefit from the increased comfort if their freedom of movement is not excessively restricted by the seat belt's strap. For this reason, the seat belt should be as loose as possible, meaning it should restrain the occupant with the lowest possible retraction force and to the smallest possible extent. At the same time, the occupant should be restrained as optimally as possible in the event of an accident.Since the occupant may be in a position or orientation that is detrimental to restraint with the seat belt during a potential accident or in the pre-accident phase due to a lack of attention or other preoccupation, improved comfort and simultaneous optimal restraint create a conflict of objectives that cannot be optimally resolved with a conventional seat belt device. Furthermore, it must be expected that the occupant, due to their reduced attention to the driving situation and their surroundings, is unprepared for the dangerous situation and therefore does not perform actions such as sitting upright, which they would otherwise do in a non-autonomous vehicle.

[0005] From the publication DE 10 2015 014 818 A1, it is also known to design the belt as a 3-point belt with a shoulder belt segment and a lap belt segment, in which the shoulder belt segment can be released via a secondary release element without releasing the lap belt segment. This allows the occupant to actively remove the shoulder belt segment in an autonomous driving situation to increase their freedom of movement.

[0006] Overall, the restraint of occupants in semi-autonomous or fully autonomous vehicles represents a special challenge, since the comfort gains created by autonomous driving should not be unnecessarily restricted, while the occupant should nevertheless be safely restrained in as many driving situations as possible.

[0007] The object of the invention is therefore to provide a safety belt device for a vehicle with at least one autonomous driving function and a method for controlling the same, which enable a safe restraint of the occupant in the event of an accident while at the same time providing good comfort during autonomous driving.

[0008] To achieve this object, a safety belt device having the features of claim 1 and a method having the features of claim 4 are proposed. Further preferred developments of the invention can be found in the subclaims, the description and the associated figures.

[0009] According to the basic idea of ​​the invention, it is proposed that at least one signaling device is provided which can be activated to emit a signal requesting the occupant to remove or put on the first belt section when at least one of the autonomous driving functions is activated or deactivated or when a signal from an external traffic control device, traffic monitoring device or road monitoring device is transmitted or when a predefined driving state exists, wherein the diagonal belt section is releasable depending on the activation of an autonomous driving function and / or depending on the existence of a predefined driving state.

[0010] In principle, various restraint characteristics and comfort features of the seat belt system can be achieved by fastening or deliberately not fastening the belt webbing sections. It can therefore generally be assumed that the driver's attention to driving will be reduced when an autonomous driving function is activated. For this reason, the driver can only activate the autonomous driving function, or the autonomous driving function can only be activated, if the occupant has previously fastened another belt webbing section and is thus better restrained. The proposed solution allows the seat belt system to be adapted to autonomous driving situations with regard to its restraint function, or the activation of the autonomous driving function can be linked to an adaptation of the seat belt system.Conversely, the seat belt device can also be adapted to deactivation of the autonomous driving function by releasing one of the two belt sections when the function is deactivated. A signaling device can be provided which prompts the occupant to fasten and / or remove the belt section. The belt sections are therefore not automatically released or locked, but the occupant is only shown that they can or must fasten the belt sections when the autonomous driving function is or is to be activated or deactivated. Alternatively, the signal to release or fasten the belt sections can also be triggered by a signal from an external traffic control device, traffic monitoring device or road monitoring device if this signal allows a conclusion to be drawn about changed driving conditions, for example.Furthermore, the signal from the signaling device can also be triggered when a predefined driving condition is detected, such as exceeding or falling below a predetermined vehicle speed. For example, if the predetermined vehicle speed is exceeded, a prompt can be displayed to fasten an additional section of belt strap, thereby improving occupant restraint and the associated safety. Conversely, if the vehicle speed falls below the predetermined speed, a message can be displayed indicating that a section of belt strap can be removed for increased comfort.

[0011] The first section of the belt is a 3-point belt with a diagonal section crossing the occupant's chest and a lap section crossing the occupant's pelvis. 3-point belts have proven themselves in practice and, due to their presumed familiarity, can be worn without further thought after proven practice. Furthermore, they offer proven safety during normal driving.

[0012] The diagonal belt section is released depending on the activation of an autonomous driving function and / or depending on the presence of a predefined driving condition, such as falling below a predetermined vehicle speed, whereby the occupant can move their upper body considerably more freely, thus improving comfort. The first belt section in the form of a 3-point belt in this case comprises two sub-sections that can be put on independently of one another, namely the diagonal belt section and the lap belt section. The diagonal belt section and the lap belt section can be connected to a belt tongue via separately detachable connections. The detachability can be achieved by an actuator actively bringing the connection into a detachable position so that the diagonal belt section can then be released manually.

[0013] It is further proposed that the second belt section be formed by a 2-point belt crossing the diagonal belt section of the 3-point belt. The 2-point belt essentially restrains the occupant in a cross-belt across both shoulders, thus at least reducing the likelihood of the occupant twisting, regardless of their seating position. The restraining forces in the belt sections can be reduced for improved comfort, as the occupant is already restrained more effectively by the cross geometry of the seat belt device, so that the overall safety of the occupant is not reduced.

[0014] The invention will be explained in more detail below with reference to various preferred embodiments. Fig. 1 a safety belt device according to the invention with a first belt section in the form of a 3-point belt, and Fig. 2 a safety belt device according to the invention with a first belt section in the form of a 3-point belt and a second belt section in the form of a 2-point belt, and Fig. 3 a safety belt device according to the invention with the second belt section applied, and Fig. 4 a safety belt device according to the invention with a lap belt section of the first belt section applied, and Fig. 5 a vehicle seat with a device to facilitate entry.

[0015] In the Fig. 1 shows an occupant sitting on a vehicle seat 10, who has fastened a first belt webbing section 2 of a safety belt device 1 according to the invention. The first belt webbing section 2 is in the form of a 3-point belt with a diagonal belt section 6 crossing the occupant's chest and a lap belt section 7 crossing the occupant's pelvis. The diagonal belt section 6 and the lap belt section 7 can each be wound on independent belt retractors 8a and 8b and can each be locked by means of a belt tongue in a belt buckle 11, so that they can be put on and taken off separately.Alternatively, the end of the diagonal belt section 6 and the end of the lap belt section 7 can also be locked via a common belt tongue in the belt buckle 11, in which case either the diagonal belt section 6 or the lap belt section 7 is firmly connected to the belt tongue, and the other section is detachably connected to the belt tongue. Furthermore, both the diagonal belt section 6 and the lap belt section 7 can be detachably connected to the belt tongue. Furthermore, two symbolically represented sensor devices 13a and 13b are provided in the belt buckle 11, which detect the locking state of the two belt tongues of the two ends of the diagonal belt section 6 and the lap belt section 7.If only one belt tongue is provided and the diagonal belt section 6 and / or the lap belt section 7 are detachably connected to the belt tongue, the sensor devices 13a and 13b detect the respective fixing of the belt strap sections relative to the belt tongue.

[0016] Furthermore, a central control and processing device 15 is provided, which is connected by signaling to a signaling device 4, the sensor devices 13a and 13b, a control unit 16 for the autonomous driving functions and a traffic control device 17, wherein the connections can be implemented both via signal lines and wirelessly.

[0017] In the in the Fig. 1, the seat belt device 1 corresponds to the geometry of a conventional 3-point seat belt. Fig. 2, the occupant has additionally worn a second belt section 3, which is designed as a 2-point belt and crosses the diagonal belt section 6 of the first belt section 2. The second belt section 3 can also be wound up with one end on a belt retractor 9 and locked with the free end via a belt tongue in a belt buckle 12. The advantage of this belt geometry is evident in the fact that the occupant is restrained symmetrically across both shoulders. Fig. 3 and Fig. 4 shows further possible belt geometries in which the occupant is restrained only via the second belt section 3 or via the lap belt section 7 of the first belt section 2.

[0018] Starting from an initial situation in which the occupant starts driving and controls all driving functions himself, the occupant is Fig. 1 is buckled in with the first belt section 2 in the 3-point geometry. In the event that an autonomous driving function is or is to be activated via the control unit 16, ie one of the driving functions, such as braking, accelerating or steering, is or is to be carried out by a control device of the vehicle itself, a corresponding warning is displayed on the signaling device 4 that the activation of the autonomous driving function requires the fastening of the second belt section 3. The signaling device 4 can emit both an optical and an acoustic signal. If the occupant then fastens the second belt section 3 to the Fig. 2, the signal from signaling device 4 goes out and the autonomous driving function is activated, provided it has not been activated previously. If the autonomous driving function does not absolutely require the fastening of the second belt section 3, the autonomous driving function can also be activated independently of the fastening of the second belt section 3, and the signal from signaling device 4 can be understood merely as a recommendation.

[0019] The occupant can then lie down to rest after fastening the second belt section 3, while the vehicle is driving in a semi- or fully autonomous mode. The reduction in safety due to the reduced attention devoted to driving is compensated for here by the occupant being restrained over both shoulders instead of one. The two belt sections 2 and 3 do not necessarily have to fit tightly; it is sufficient if the two belt sections 2 and 3 fit with a slight slack, so that the occupant does not feel the two belt sections 2 and 3, but is immediately restrained in the event of an accident-related movement. The belt retractors 8a, 8b and 9 can each be equipped with reversible drive devices, such asElectric motors, which drive the belt shafts in the belt retractors 8a, 8b or 9 in the winding or unwinding direction and thereby control the belt slack such that identical retraction forces act in both belt sections 2 and 3 or the same belt slack is present. The belt forces can be increased briefly or repeatedly in the form of vibrations by the drive devices in the event of a detected potentially critical driving situation, whereby the occupant can be warned and, in extreme cases, even woken up so that they can subsequently devote increased attention to driving and, if necessary, resume the functions of autonomous driving. Furthermore, the existing belt slack can be pulled out to couple the occupant to the vehicle deceleration at an earlier stage.

[0020] Alternatively, it is also possible, if a predefined driving condition such as driving below a defined speed is detected, to transmit information via the signaling device 4 that the driving situation would allow, for safety reasons, either the first belt section 2 as a whole or the diagonal belt section 6 of the first belt section 2 to be released and the occupant to be led only via the lap belt section 7 of the first belt section 2 or only via the second belt section 3 to the Fig. 3 and Fig. 4 shown geometries. Such a driving situation can occur, for example, in traffic jams or during longer waiting times, in which the probability of serious accidents is at least reduced.

[0021] In this case, the signals from the sensor devices 13a, 13b and 14 assigned to the belt buckles 11 and 12, the signals from a control unit 16 controlling autonomous driving and the signals from an external traffic control device 17, a traffic monitoring device or even a road monitoring device can be taken into account in the central control device 15 to generate the warning and information signals or to control the seat belt device 1. The control device 15 can also transmit a direct control command to release the locks in the belt buckles 11 and 12, provided these are equipped with corresponding actuators. The display of the information or warnings via the signaling device 4 and the manual release and locking or the taking off and putting on of the belt sections 2 and 3 orHowever, the diagonal belt section 6 and the lap belt section 7 are preferable, as this still requires manual action by the occupant. The occupant must practically initiate the action themselves. This eliminates the likelihood of inadvertent activation or unintentional release of belt sections 2 and 3.

[0022] An algorithm can be stored in the control device 15 for controlling the safety belt device 1 or for displaying the warning and information instructions on the signaling device 4, with the aid of which the corresponding warning, information, or control signals are generated from the signals of the sensor devices 13a, 13b, 14 of the belt buckles 11 and 12, the signals of the control unit 16 for autonomous driving, and the external traffic control device 17. For example, conditions are conceivable in which the vehicle is completely controlled by the occupant. In such conditions, the occupant should, according to Fig. 1 can only be restrained with the first belt section 2 in the 3-point geometry with a diagonal belt section 6 and a lap belt section 7. If the control unit 16 assumes certain or only individual functions for partially or fully autonomous driving, it is advisable, taking into account the degree of danger and in order to create the greatest possible wearing comfort, to restrain the occupant either with the additional belt section 3 (the 2-point belt) and with lower retraction forces or with fewer belt sections by releasing the diagonal belt section 6.

[0023] In the Fig.Figure 5 shows a further improvement of the invention, in which the vehicle seat 10 can additionally be moved laterally on a slide rail system 19 into a position more favorable for entry. The safety belt device 1 is held in an ergonomically favorable position by a detachable holder 18 of the belt ends of the diagonal belt section 6 and the lap belt section 7 at a fastening point located in the center of the vehicle, so that the occupant can sit on the vehicle seat 10 without being obstructed by the safety belt device 1.

Claims

[1] Safety belt device (1) for a vehicle with at least one autonomous driving function with at least -a first belt section (2) wherein -the first belt section (2) is formed by a 3-point belt with a diagonal belt section (6) crossing the chest of the occupant and a lap belt section (7) crossing the occupant's pelvis, characterized by , that -at least one signaling device (4) is provided which can be activated to emit a signal requesting the occupant to remove or put on the first belt section (2) when at least one of the autonomous driving functions is activated or deactivated or when a signal is transmitted to an external traffic control device (17), traffic monitoring device or road monitoring device or when a predefined driving condition exists, wherein -the diagonal belt section (6) is releasable depending on the activation of an autonomous driving function and / or depending on the presence of a predefined driving state. [2] Safety belt device (1) according to claim 1, characterized by , that -the predefined driving state is a driving speed below a specified vehicle speed. [3] Safety belt device (1) according to one of claims 1 or 2, characterized by , that -the second belt section (3) is formed by a 2-point belt crossing the diagonal belt section of the 3-point belt. [4] Method for controlling a safety belt device (1) for a vehicle with at least one autonomous driving function with -a first strap section (2) and -a second strap section (3), characterized by , that -at least one signaling device (4) is provided which is activated to emit a signal requesting the occupant to remove or fasten a belt section when at least one of the autonomous driving functions is activated or deactivated or when a signal is transmitted from an external traffic control device (17), traffic monitoring device or road monitoring device or when a predefined driving condition exists, and -at least one of the belt sections (2, 3) is wound on a belt retractor (8a, 8b, 9) with a reversible drive device, and -the reversible drive device is controlled depending on the activation or deactivation of one of the autonomous driving functions to reduce or increase the belt tension in the belt section. [5] Method according to claim 4, characterized by , that -the first belt section (2) is wound up by means of a first and the second belt section (3) is wound up by means of a second reversible drive device, and -the first and second drive devices are controlled to achieve identical belt forces in the two belt sections (2,3) when both belt sections (2,3) are fastened.

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