VEHICLE STEERING WHEEL WITH CONTROL DEVICE

Abstract

A vehicle steering wheel (18) with an operating device (20) is shown, which comprises a touchpad (22) having a smooth, plate-like operating surface (30). The operating surface (30) can be divided into a plurality of virtual switch fields (32) of associated virtual switches, which merge seamlessly and without obstructions. The touchpad (22) is configured to provide a plurality of different arrangements of switch fields (32), wherein an active haptic feedback system (36) is provided on the touchpad (22), which delimits or defines the switch fields (32) by actively generated haptic signals. The feedback system (36) is adaptable to the different arrangements of the virtual switch fields (32) in order to change the locations on the operating surface (30 upon contact with which feedback is provided. Furthermore, a control unit (34) of a vehicle (12) with a vehicle steering wheel (18) and a display (44) is shown.

Description

The invention relates to a vehicle steering wheel having an operating device which comprises a touchpad. The invention furthermore relates to a control unit of a vehicle having such a vehicle steering wheel.Touch pads, as are also found in computers, are already widely used in the vehicle interior, for example on the dashboard for setting the heating or on the steering wheel for accepting incoming calls via a hands-free system. Instead of touchpads, touch screens are often also used, which are preferred in places because of the integrated display, since they display the selection options directly. However, exactly because of the display function of the display, the driver quickly experiences a distraction, which is to be avoided.The problem with using touchpads is that it may be difficult for the driver to identify where exactly one finger is located, thus making the orientation and operation of the touchpad more difficult.It is known from the prior art to equip touchpads with mechanical sensing aids, although these are too non-dynamic for the display-guided operator control elements customary today.It is therefore an object of the invention to provide a vehicle steering wheel with an operating device, the actuation of which keeps the distraction of the driver as low as possible.This object is achieved according to the invention by a vehicle steering wheel having an operating device which comprises a touchpad which has a smooth, plate-like operating surface. The user interface is divided into a plurality of virtual switch fields of assigned virtual switches, which merge into one another without gaps and without obstacles. The touchpad is configured to provide a plurality of different arrangements of switch fields, wherein an active haptic feedback system is provided on the touchpad, which active haptic feedback system limits or defines the switch fields by actively generated haptic signals. The feedback system can be electronically adapted to the different arrangements of the virtual switch fields in order to change the locations on the operating surface at the contact of which feedback is given. In other words, the smooth, plate-like operating surface of the touchpad has no protruding or recessed edges for haptically delimiting a switch panel from an adjacent one and can be occupied haptically differently depending on the function. As a result, the touchpad can be adapted to the respective driving situation or to a selected function assignment and provides the necessary guidance aids, so that the driver does not have to turn his eyes off the road and can keep the traffic constantly in his eye.The touchpad is in particular a sensitive surface, that is to say an alternative to a display or a touch display. Different arrangements are understood to mean both a change in the function assignment and a change in the number and size of the virtual buttons. Thus, for example, virtual switches other than those required for operating an air-conditioning system are required for operating a radio. Based on the selected function assignment, the number and size and / or arrangement of the virtual switch fields and of the corresponding virtual switches are thus adapted.A non-limiting example of this is that in radio operation, the touchpad is divided into two rows and three columns, in which the total of six areas define buttons for radio operation. In the air conditioner operation, on the other hand, the touch pad is divided into two rows and two columns, i.e., only four, then larger buttons. Of course, a central, round button could also be defined, to the circumference of which four buttons follow.Preferably, when contacting a boundary region at the respective lateral end of the virtual switch fields, haptic feedback is generated to create a virtual haptic boundary structure. Thus, the smooth, plate-like operation surface of the touch pad can be maintained, and simultaneously, operation aids can be provided to the driver. The haptic feedback does not have to be generated continuously, but it is sufficient if it is generated when contacting the boundary region of a virtual switch field. This allows energy to be saved and the driver is not incorrectly distracted by haptic feedback when the touchpad is not used.According to one specific embodiment, the operating device is configured to generate haptic feedback upon an actuation of a virtual switch. The haptic feedback is different when an virtual switch is actuated and when the haptic delimiting structure is contacted. Thus, the driver can directly feel whether he has just touched the boundary area of a virtual switch panel or has operated the virtual switch panel.In addition, the threshold for triggering the haptic feedback of the different functions, i.e. the triggering for confirming the actuation of a virtual switch and the haptic feedback when contacting the haptic delimiting structure, may be different.In order to feel the haptic feedback for the haptic delimiting structure of the virtual switch fields in the operating surface, a finger must slide over the touchpad. As soon as the finger reaches the edge of a switch panel, vibration pulses are introduced which are to be sensed on the outer surface.If a movement takes place perpendicular to the touchpad when a virtual switch is to be actuated, or if the finger rests on a switch field for a predefined time, a conclusion is drawn as to an actuation request. Then we generate another haptic signal on the surface, e.g. one or two short "beats" simulating a click of a real switch.According to one embodiment, the operating device comprises at least one electric actuator for generating the haptic feedback. The advantage of an electric actuator is that the electric actuator can generate pulses of high intensity and large acceleration values are possible. This leads to the driver's impression of high quality haptics with rapid feedback.The haptic feedback is preferably generated perpendicular to the operating surface in order to be as perceptible as possible to the driver.Alternatively, actuators can also be used which are based, for example, on the piezo effect or the attractive force of a magnetic field. In principle, any type of actuator that can generate haptic feedback can be used for generating the haptic feedback.The haptic feedback is preferably generated by at least one, preferably by a plurality of, piezo actuators attached below the operating surface, which generate waves or oscillations in the wall defining the operating surface.If more than one actuator is assigned to the user interface, the actuators can be controlled in such a way that the oscillations generated at the instantaneous contact-making point of the user interface are structurally superimposed, i.e. it is sensed where a finger is and it is calculated as a function of how the individual actuators must oscillate with respect to one another in time in order to be superimposed and amplified at the contact-making point.According to a further embodiment, the operating device comprises at least one sensor which is configured to measure the operating force on the touchpad. A triggering threshold for the haptic feedback can thus be individually defined, in particular also for the different types of haptic feedback.In principle, the operating device can also comprise other sensors in its sensor system, which sensors detect the triggering threshold for the haptic feedback. The sensor system can be designed as a capacitive, inductive or optical system based on whether an approach, mere contact or actuation force should lead to the triggering of the haptic feedback.According to a preferred embodiment, the operating device comprises a controller which is configured to assign a function to the virtual switches in accordance with the current arrangement of their switch fields and / or to actuate an actuator for the haptic feedback. The controller is thus responsible for the flexible occupancy of the switches and can assign a function to the virtual switches depending on the driving situation, so that generally fewer switches are necessary.The operating device can also comprise at least two or more touchpads, in particular on opposite spokes. Alternatively or additionally, the operating device, in particular the touchpad, can be positioned on a front side of an airbag cover. In other words, the at least one touchpad can be positioned on the vehicle driver in such a way that it can be easily reached at any time for the driver without the driver having to take his attention from the current road traffic.According to one embodiment, the vehicle steering wheel has, in addition to the touchpad and remote therefrom, a switch which serves as a selection switch for the virtual switches or as a function switch. The driver can thus also specifically control the occupancy of the virtual switches and is not dependent on the control in order to assign the occupancy of the virtual switches.In this case, it is possible that by actuating the swerving switches or function switches, different tones are generated which serve as acoustic feedback in order to indicate the current occupancy of the operating device.The object is also achieved according to the invention by a control unit of a vehicle having a previously described vehicle steering wheel and a display. The display is arranged at a distance from the touchpad in the vehicle interior and is electronically coupled to the touchpad. The display is configured to display the current arrangement of the virtual switches on the touchpad. This makes it possible to ensure that the driver can check at any time how the virtual switches of the operating device are currently occupied. Because the display is located remote from the touchpad in the vehicle interior, the display can be positioned to be in the general field of vision of the driver, so that the driver does not need to look away from the road to see the display.The display is preferably located remote from the steering wheel, in particular above the steering wheel. In other words, the display is preferably integrated into the head-up or is designed as its own display in the field of vision of the driver.Further advantages and features of the invention will become apparent from the following description and from the drawings to which reference is made. In the drawings, there are shown:FIG. 1 shows a schematic illustration of a vehicle interior with a vehicle steering wheel according to the invention and a control unit according to the invention;FIG. 2 is a schematic illustration of another embodiment of the vehicle steering wheel;FIG. 3 shows a schematic illustration of a haptic feedback system for triggering haptic feedback;FIG. 4 is a schematic illustration of a control unit for a vehicle according to the invention;FIG. 5 is a schematic illustration of an exemplary touchpad used in the invention with various arrangements of virtual buttons; andFIG. 6 shows a schematic illustration of a further embodiment of the haptic feedback system.FIG. 1 shows a vehicle interior 10 of a vehicle 12. On the driver side, the dashboard 14 has the head-up display 16 and the vehicle steering wheel 18, which together form a control unit 19 or are part of a control unit.The vehicle steering wheel 18 comprises an operating device 20 which, in FIG. 1, has two touchpads 22 which are arranged on opposite spokes 24 of the vehicle steering wheel 18.It is likewise conceivable for only one touchpad 22 or more than two touchpads 22 to be used, it also being possible for the touchpads 22 to be positioned on a front side of an airbag cover 26 in addition to the spokes 24. An arrangement of the operating device 20 on the front side of the airbag cover 26 is shown, for example, in FIG. 2.As can be seen in the embodiment of the vehicle steering wheel 18 shown in FIG. 2, the vehicle steering wheel 18 can have, in addition to the touchpad 22, switches 28 which supplement the operating device 20. The switches 28 may be pressure switches or conventional mechanical switches, the function of which will be explained later.The touchpad 22 has a smooth, plate-like operating surface 30. That is, the user interface 30 does not include any mechanical structures or sensing aids as are known in the art. In addition, the user interface 30 of the touchpad 22 does not comprise any embossed or protruding graphics or symbols.However, the user interface 30 is divided into a plurality of virtual switch fields 32 of associated virtual switches. Since this is a smooth, plate-like operating surface 30, the virtual switch fields 32 merge into one another without gaps and without obstacles. The virtual switch fields 32 are indicated in FIG. 2 by dashed lines.The operating device 20 also comprises a controller 34. the controller 34 is configured to provide various arrangements of virtual switch arrays 32 on the touchpad 22 and assign a function to the virtual switches according to the current arrangement of their virtual switch arrays 32. The function may represent a basic functionality of the vehicle 12, such as a gear shift or a functionality of an assistance system of the vehicle 12, such as a cruise control. In principle, the function can be any functionality of the vehicle 12.In Figure 5, two different arrangements of the virtual switch arrays 32 are shown. The virtual switch fields 32 shown in dashed lines are function assignments for operating a radio, while the solid lines delimit the virtual switch fields 32 for operating an air-conditioning system. Consequently, the arrangement of the virtual switch fields 32 on the operating surface 30 of the touchpad 22 is adapted to the selected function assignment, such that the number, size, arrangement and functionality of the virtual switch fields 32 differ depending on the arrangement. It would also be possible to design the switch fields not only as tap keys but as rotary keys. Thus, for example, the adjustment of the temperature could be configured as a rotary button as usual in the past, which is virtually simulated. If the system is thus switched to an air conditioning system, the driver could circle around a virtual center, which is indicated haptically, by means of the finger around this center in order to quickly raise the temperature, as in the case of a rotary controller.Finally, the driver could also use the function keys 28 to set whether he would like to have simulated rotary controls or key keys, so to speak as a preferred basic setting for him. This allows older drivers to continue their usual switch operation in a current vehicle.In order to keep the driver's distraction as low as possible and to simplify an orientation on the touchpad 22, the operating device 20 comprises an active haptic feedback system 36. The active haptic feedback system 36 therefore provides feedback in accordance with the boundaries of the virtual switch fields 32 when in contact with the user interface 30.In particular, when a border region, represented by the dashed lines in FIG. 2, contacts each of the lateral end virtual switch arrays 32, a virtual haptic border structure is generated by the haptic feedback system 36.Furthermore, the haptic feedback system 36 is able to generate a haptic feedback when a virtual switch is actuated, which is different from the virtual haptic boundary structure.For this purpose, the operating device 20 comprises at least one electric actuator 38, as can be seen, for example, in the haptic feedback system 36 shown in FIG. 3. In addition to the electric actuator 38, the haptic feedback system 36 also comprises a sensor 40, which is designed here as a force sensor. The sensor 40 thus serves to measure the operating force on the touchpad 22.In addition, the haptic feedback system 36 comprises a position sensor 41, which can determine the exact position of the contacting with the operating surface 30. The position sensor 41 is preferably a capacitive sensor in the touchpad 22.Both the sensor 40 and the electric actuator 38 are connected to the controller 34, such that the haptic feedback can be generated based on the measured operator. The controller 34 thus controls the haptic feedback actuator 38 based on the measured operator.The controller 34 is also connected to the switches 28 which allow manual change in the arrangement of the virtual switch arrays 32 and their assigned functions. Therefore, the switch 28 is also referred to as a selection switch or a function switch. The switch 28 is preferably arranged at a distance from the touchpad 22.Preferably, the switches 28 are also located on the vehicle steering wheel 18, but it is also conceivable for the switches 28 to be arranged at another location that is easily accessible to the driver, such as the turn signal levers 42 or the dashboard 14.When the switches 28 are actuated, acoustic feedback can be provided, which signals the driver the current function assignment of the virtual switch fields 32.Additionally, a display 44 may be provided that is disposed remotely from the touchpad 22 in the vehicle interior 10 and is electronically coupled to the touchpad 22. The display 44 serves to display the current arrangement of the virtual switch fields 32 or the virtual switches on the touchpad 22.The display 44 can be a separate display 44, e.g. in the dashboard, or a display 44 integrated into the head-up display 16, i.e. a field in the head-up display 16.As an alternative to a display 44, only one display integrated into the head-up display 16 can also be provided. It is only important that the display 44 or display be arranged so that the driver can recognize the current arrangement of the virtual switch panels 32 without turning his eyes off the road and traffic.In FIG. 4, for example, an embodiment of the control unit 19 is shown in which the selected function assignment of the user interface 30 is shown by an integrated display in the head-up display 16.In the embodiment shown in FIG. 4, the control unit 19 has two operating surfaces 30, which are each arranged in the spokes 24 of the vehicle steering wheel 18. Directly below the user interfaces 30 are the switches 28 which are used for selecting the function assignment. The selected switch 28 is displayed in the display in the head-up display 16, here in the display 44 integrated therein, so that the driver can see the current function occupancy.Alternatively, the display or the display 44 can also display the entire user interface 30 with the respective virtual switches 32 and their current function assignment.In FIG. 6, an alternative embodiment of the haptic feedback system 36 is shown, wherein piezo actuators 46 are used instead of or in addition to the electrical actuator 38. Preferably, as can also be seen in FIG. 6, two or more piezoelectric actuators 46 are provided, which are each attached to opposite ends below the operating surface 30.The position sensor 41 is connected to the controller 34 so that the piezo actuators 46 can be controlled by the controller 34 in such a way that the generated vibrations are superimposed in an amplifying manner at the contacting point. Piezoelectric actuators 46 with a low power can thus also be used, since the haptic feedback generated can be felt sufficiently strongly due to the constructive interference at the contact point.

Claims

Vehicle steering wheel (18) having an operating device (20) which comprises a touchpad (22) which has a smooth, plate-like operating surface (30), wherein the operating surface (30) can be divided into a plurality of virtual switch fields (32) of associated virtual switches which merge into one another without joints and without obstacles, wherein the touchpad (22) is configured to provide a plurality of different arrangements of switch fields (32), wherein an active haptic feedback system (36) is provided on the touchpad (22), which active haptic feedback system limits or defines the switch fields (32) by active generated haptic signals, wherein the feedback system (36) is electronically adaptable to the different arrangements of the virtual switch fields (32) in order to change the locations on the operating surface (30) at the contact of which feedback is provided.Vehicle steering wheel (18) according to Claim 1, characterized in that the operating device (20) is configured, when a boundary region at the respective lateral end of the virtual switch fields (32) is touched, to generate haptic feedback for creating a virtual haptic delimiting structure.Vehicle steering wheel (18) according to one of Claim 2, characterized in that the operating device (20) is configured to generate haptic feedback when a virtual switch is actuated, wherein the haptic feedback is different when a virtual switch is actuated and when the haptic delimiting structures are contacted.Vehicle steering wheel (18) according to one of the preceding claims, characterized in that the operating device (20) comprises at least one electric actuator (38) in order to generate the haptic feedback.Vehicle steering wheel (18) according to one of the preceding claims, characterized in that the operating device (20) comprises at least one sensor (40) which is configured to measure the operating force on the touchpad (22).Vehicle steering wheel (18) according to one of the preceding claims, characterized in that the operating device (20) comprises at least one position sensor (41) which is configured to determine the position of the contact with the touchpad (22).Vehicle steering wheel (18) according to one of the preceding claims, characterized in that the operating device (20) comprises a controller (34) which is configured to assign a function to the virtual switches in accordance with the current arrangement of their switch fields (32) and / or to actuate an actuator (38) for the haptic feedback.Vehicle steering wheel (18) according to one of the preceding claims, characterized in that the operating device (20) comprises at least two or more touchpads (22), in particular on opposite spokes (24), and / or the operating device (20) is positioned on a front side of an airbag cover (26).Vehicle steering wheel (18) for a vehicle (12) having an operating device (20) according to one of the preceding claims, wherein the vehicle steering wheel (18) has, in addition to the touchpad (22) and remote therefrom, a plurality of switches (28) which serve as selection switches for the virtual switches or as function switches.Control unit (19) of a vehicle (12) having a vehicle steering wheel (18) according to one of the preceding claims and a display (44) which is seated in the vehicle interior (10) at a distance from the touchpad (22) and is electronically coupled to the touchpad (22) and is configured to display the current arrangement of the virtual switches on the touchpad (22).Control unit (19) according to Claim 10, characterized in that the display (44) is seated remote from the vehicle steering wheel (18), in particular above the vehicle steering wheel (18).

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