GB2426316A

GB2426316A - Steering wheel having moveable element activated in response to driver tiredness.

Info

Publication number: GB2426316A
Application number: GB0510150A
Authority: GB
Inventors: Alexander Gulde
Original assignee: Autoliv Development AB
Current assignee: Autoliv Development AB
Priority date: 2005-05-18
Filing date: 2005-05-18
Publication date: 2006-11-22
Also published as: GB0510150D0

Abstract

A steering wheel 1 is installed in a motor vehicle and connected to a monitoring arrangement 3, configured to provide a signal to the steering wheel in response to a driver using the wheel being tired. The steering wheel incorporates a moveable element 16 and an actuator 18. The actuator may be actuated in response to a signal from the monitoring arrangement to move the moveable element to alter the dimensions of a section of a rim 12 of the wheel to alert the driver. The steering wheel thus provides a tactile alert signal to the driver.

Description

A STEERING WHEEL

Description of Invention

THE PRESENT INVENTION relates to a steering wheel, and more particularly relates to a steering wheel which is adapted to provide an alert signal to a user of the wheel.

A large number of accidents arise each year as a result of drivers driving motor vehicles, in particular cars and lorries, when they are tired. A driver may be tired as a result of having had too little sleep, for instance when driving on a long journey.

The response times of a tired driver are significantly greater than the response times of a well rested driver. Hence a tired driver is less likely to respond quickly in a hazardous situation. A tired driver is also less attentive than a well rested driver, and thus more likely to not see a potential hazard, increasing the chances of the driver being involved in an accident. At worst, a tired driver may fall asleep whilst driving a vehicle, and thus be completely unaware of the behaviour of the vehicle and any potential hazards, making the chances of an accident occurring extremely high.

Modern vehicle manufacturers invest significant amounts of time and money into developing systems which are for detecting whether or not a driver is tired.

One prior proposed detection system monitors the eyelids of a driver, and detects the period of time for which the driver's eyes are closed when the driver blinks. If the driver's eyes are closed for a length of time which is above a predetermined threshold, for instance if the driver's eyes are completely closed as a result of the driver falling asleep, the system issues a warning signal to alert or wake the driver.

There are many different ways in which a tired driver can be alerted or woken.

For instance, a loud noise can be emitted inside the vehicle to wake the driver, or lights within the vehicle can flash in front of the driver to wake the driver.

However, alerting, or waking, a driver suddenly by exposing the driver to a loud sound, or bright lights, can result in the driver being startled which may confuse and disorientate the driver. This may result in the driver losing control of the vehicle and being involved in an accident.

Therefore, it is desirable to have a system within a vehicle which can provide an alert signal to a driver which makes the driver more alert, whilst minimising the chances of the driver becoming confused or disoriented.

The present invention seeks to provide an improved steering wheel.

According to one aspect of the invention, there is provided a steering wheel having a rim, the steering wheel incorporating a system operable to alter the dimensions of at least a section of the rim in response to a predetermined signal, to provide an alert signal to a driver using the wheel.

Preferably the system operable to alter the dimensions of at least a section of the rim comprises at least one movable element which is moveably mounted within the rim, and at least one actuator, the or each actuator being adapted to move the or each said moveable element outwardly from the rim in response to the said predetermined signal to alter the dimensions of a section of the rim.

In one embodiment the rim comprises one moveable element in the form of a resilient split ring, the split ring having a cutaway section which defines two ends between which a said actuator is mounted, the actuator acting upon at least one of the said ends of the cutaway section in response to the said predetermined signal, to deform the split ring, so that the split ring alters the dimension of at least a section of the rim.

In another embodiment the rim comprises at least two discrete moveable elements, with each said moveable element being adapted to be moved by a respective actuator in response to the said predetermined signal.

In a further embodiment the or each actuator comprises a solenoid having a moveable core, the or each actuator being actuated by an electrical current being supplied to the solenoid to move the core, with movement of the core resulting in movement of the or each said moveable element.

In a still further embodiment the or each actuator is a hydraulic actuator which is adapted to move the or each said moveable element when a pressurised fluid is supplied to the or each hydraulic actuator in response to a predetermined signal.

In another embodiment at least a part of the surface of the at least one moveable element forms at least part of an outer surface of the rim.

Preferably the rim is at least partly covered by a deformable cover, with the deformable cover being deformable when the system alters the dimensions of at least a section of the rim in response to the predetermined signal.

According to another aspect of the invention, there is provided a vehicle incorporating the steering wheel defined above, wherein the vehicle further incorporating a monitor arrangement for monitoring the driver of the vehicle, and a control unit, the control unit being adapted to provide the said predetermined signal to the system to alter the dimensions of at least part of the rim in response to a signal from the monitor arrangement which is indicative of the driver being tired.

Preferably the control unit provides the said predetermined signal in response to the driver being tired, and in response to a sensed parameter corresponding to an impending hazard, with the dimensions of a predetermined section of the rim being altered to alert a driver using the wheel, to influence the driver into turning the wheel in a predetermined direction, to steer the vehicle away from the hazard.

In order that the invention may be more readily understood, and so that further features thereof may be appreciated, the invention will now be described, by way of example, with reference to the accompanying drawings in which: FIGURE us a diagrammatic bectional view of part of a motor vehicle in which a steering wheel in accordance with a preferred embodiment of the invention is installed, with the steering wheel being connected to an arrangement for monitoring the drowsiness of a driver, FIGURE 2 is a diagrammatic sectional plan view of the steering wheel of Figure 1, in a normal condition, FIGURE 3 is a diagrammatic sectional side view of the steering wheel of Figure 1, in a normal condition, FIGURE 4 is a view corresponding to Figure 2, with the steering wheel in a distorted condition, FIGURE 5 is a view corresponding to Figure 3, with the steering wheel in a distorted condition, FIGURE 6 is a diagrammatic sectional plan view of a steering wheel in accordance with an alternative embodiment of the invention, with the steering wheel in a normal condition, and FIGURE 7 is a view corresponding to Figure 6, with the steering wheel in a distorted condition.

Referring initially to Figure 1, a steering wheel I in accordance with a preferred embodiment of the invention is installed in a motor vehicle 2. The steering wheel I is connected to a monitoring arrangement 3 for monitoring the eyelids 4 of a driver 5 to ascertain whether the driver 5 is drowsy, or falling asleep.

The monitoring arrangement 3 has a camera 6 that is positioned on part of a dashboard 7 of the vehicle 2, in front of the driver 5. The camera 6 is connected to a processor 8, and the processor 8 is connected to a control unit 9. The control unit 9 is connected to the steering wheel 1. When a driver 5 is driving the vehicle 2, the camera 6 monitors the eyelids 4 of the driver 5, and transmits information to the processor 8. The processor 8 processes the information, to determine the length of time for which the eyes of the driver 5 are closed when the driver blinks. The processor 8 transmits data to the control unit 9 corresponding to the measured time for which the driver 5's eyes are closed. The control unit 9 compares the times for which the driver S's eyes are closed with a predetermined threshold, and if the period of time is longer than the predetermined length of time, signifying that the driver 5 is drowsy or falling asleep, the control unit 9 transmits an actuation signal to the steering wheel 1. The actuation signal actuates the steering wheel I so that the steering wheel I provides an alert signal to the driver 5 to alert or wake the driver 5. The way in which the steering wheel I provides the alert signal to the driver 5 will become clear from the following description.

Referring now to Figures 2 and 3, the steering wheel I can be seen in a partly cutaway form with some of an outer jacket of the wheel I having been removed. The steering wheel I incorporates a central hub 10 which is configured to allow the steering wheel I to be mounted on a steering column of the vehicle 2. Four spokes 11 extend upwardly and outwardly from the hub 10, to connect to a rim 12 to support the rim 12.

The rim 12 incorporates a central metal core 13 which is covered by a layer of foam 14. The central core 13 ensures that the rim 12 remains rigid, and the foam 14 is provided to make the rim 12 comfortable to hold. The foam 14 extends axially around the central core 13, and the foam 14 incorporates a groove 15 which extends around the outer edge of the rim 12. A moveable element in the form of a split ring 16 is installed within the groove 15, with the split ring 16 extending most of the way around the circumference of the rim 12.

The split ring 16 is of a resilient material and defines a shape which is effectively a ring which is split by a cutaway section 17. The inner edge of the split ring 16 is shaped so as to correspond with the shape of the groove 15.

The split ring 16 is dimensioned so that when the split ring 16 is installed within the groove 15 the outer edge of the split ring 16 is flush with the outer edge of the rim 12. The split ring 16 is orientated so that the cutaway section 17 is positioned adjacent the lowest point of the rim 12 when the steering wheel 1 is "straight", as seen in Figure 2.

Part of the groove 15 which is adjacent the cutaway section 17 of the split ring 16 is enlarged so as to receive an actuator 18. The actuator 18 is mounted within the enlarged part of the groove 15, and positioned between the ends of the split ring 16 which define the edges of the cutaway section 17.

In this preferred embodiment, the actuator 18 is in the form of a solenoid 19 that consists of a coil of wire which defines a hollow tube. A metal core 20 of a diameter which is slightly less than the diameter of the tube of the solenoid is positioned within the solenoid 19 for slideable movement relative to the solenoid 19. The length of the metal core 20 is slightly less than the width of the cutaway section 17, so that when the metal core 20 is inserted within the solenoid 19 each end of the metal core 20 contacts a respective end of the split ring 16 which forms an edge of the cutaway section 17.

A wire 21 is connected to the solenoid 19, and the wire extends part-way around the inner edge of the rim 12, down one of the spokes 11, to be connected to the control unit 9, so that the control unit 9 can supply an electrical current to the solenoid 19.

In the event that the monitoring arrangement 3 determines that a driver using the steering wheel I is drowsy or falling asleep, the control unit 9 provides a predetermined signal, in the form of an electrical current, to the solenoid 19 via the wire 21. The electrica current flows around a coil of wire within the solenoid 19, and the flow of current results in a magnetic field being generated in a direction which passes through the tube defined by the solenoid 19. The magnetic field acts upon the metal core 20 to move the metal core 20 in a direction dependent upon the direction of the magnetic field. The metal core will thus be moved outwardly from one end of the solenoid 19 in response to the electrical current, and it is to be appreciated that which end out of which the metal core 20 moves is dependent upon the direction of the electrical current which flows around the solenoid 19. The direction in which the metal core 20 is moved can thus be set by the control unit 9, according to the direction in which the electrical current is passed around the solenoid 19.

If the control unit 9 controls the solenoid 19 to move the metal core 20 out from the right hand end of the solenoid 19, as seen in Figures 4 and 5, the metal core 20 will push against one end of the split ring 16, which forms a right edge of the cutaway section 17. The metal core 20 will exert a force on that end of the split ring 16, and as the split ring 16 is of a resilient material, the split ring 16 will bend outwardly from the rim 12, in a direction generally indicated by arrows 22, causing the right hand side of the rim 12 of the steering wheel I to effectively become wider as the dimensions of the rim 12 are altered. A driver holding the steering wheel I will thus feel the dimensions of the rim 12 change, which will provide a tangible signal to the driver, to wake the driver, or alert the driver to a hazard.

Once the monitoring arrangement 3 has identified that the driver is no longer drowsy or falling asleep, the control unit 9 ceases to supply the electrical current to the solenoid 19. The removal of the current flowing within the solenoid 19 removes the magnetic field acting upon the metal core 20. As the split ring 16 is of a resilient material, the split ring 16 will return to its original shape, as seen in Figure 2, and push the metal core 20 back to its initial position within the solenoid 19.

It is to be appreciated that the control unit 9 may supply a series of current pulses to the solenoid 19, making the metal core 20 move in and out from the solenoid 19 repeatedly, causing the dimension of the rim 12 to be altered repeatedly to alert the driver.

If the control unit 9 control the solenoid 19 to move the metal core 20 outwardly from the left hand end of the solenoid 19, the metal core 20 will act upon the end of the split ring 16 which forms the leftmost edge of the cutaway section 17 to deform the left hand side of the split ring 16 outwardly. In this case, the dimensions of the left hand side of the rim 12 will be altered as the left hand side of the split ring 16 deforms outwardly.

The control unit 9 can thus select which side of the rim 12 of the steering wheel I is to be distorted by controlling the direction of the current supplied to the solenoid 19. In this preferred embodiment the control unit 9 selects which side of the rim 12 is to be distorted, according to parameters relating to the environment surrounding the vehicle, or an impending hazard which a driver may be encountering. One such parameter may be the direction of the road in front of the vehicle, along which the vehicle is being driven. For instance, if the monitoring arrangement 3 determines that a driver of the vehicle is drowsy, and the road along which the vehicle is being driven bends to the left, then the control unit 9 supplies an electrical current to the solenoid 19 to push the metal core 20 out from the right hand end of the solenoid 19. As the metal core 20 is pushed out from the right hand end of the solenoid 19, the right hand side of the split ring 16 is distorted, and the dimensions on the right hand side of the rim 12 are altered. When the driver of the vehicle feels the right hand side of the rim 12 of the steering wheel I is becoming enlarged the driver will most likely turn the steering wheel I in an anticlockwise direction, which will result in the vehicle turning left and thus more likely to turn around the left hand bend, potentially avoiding an accident situation.

It is to be appreciated that the actuator 18 can thus be used to alter the dimensions of both the left hand side and the right hand side of the rim 12, to try to make a driver holding the wheel turn the wheel in a particular direction to avoid a hazard. In some situations, it may not be appropriate to alter the dimensions of one particular side of the rim 12, and in this case, the control unit 9 supplies pulses of current to the solenoid 19 which alternate in direction, thus changing the dimensions both the left hand side and the right hand side of the rim 12 in turn. In this case a driver holding the wheel I will experience the same tactile sensation on both hands, which will thus most likely alert the driver, without the driver being influenced into turning the wheel I in a particular direction.

Referring now to Figure 6, an alternative embodiment of the invention has a pair of moveable elements in the form of arcuate sections 23,24. The arcuate sections 23,24 are identical to one another, and each forms one half of a ring, which is equivalent to the split ring 16 of the preferred embodiment described above. One of the arcuate sections 23 is installed in the groove 15 on the left hand side of the rim 12, and the other arcuate section 24 is installed in the groove 15 on the right hand side of the rim 12.

One of a pair of actuators 25,26 is mounted within the rim 12 adjacent the inner side of a respective one of the pair of arcuate sections 23,24. The actuators 25,26 are solenoid actuators of the type described above, and each of the actuators 25,26 is connected by a respective wire 27,28 to the control unit 9. It is to be understood that each of the arcuate sections 23,24 is independently moveable by a respective actuator 25,26.

In the event that the monitoring arrangement 3 detects that a driver using the steering wheel I is drowsy or falling asleep, the control unit 9 sends a signal, in the form of an electrical current, to one or both of the actuators 25,26.

In the case when the driver is found to be drowsy or falling asleep, and the control unit 9 determines that the driver must turn the wheel in a clockwise sense to steer the vehicle to the right to avoid a hazard, the control unit 9 sends a signal to actuate the left hand actuator 25. The actuator 25 exerts a force on the inner edge of the left hand arcuate section 23 to move the left hand arcuate section 23 radially outwardly from the steering wheel 1, in a direction generally indicated by arrow 29, to alter the dimensions of the left hand side of the rim 12, as seen in Figure 7. The change in dimensions of the left hand side of the rim 12 can thus provide an alert signal to wake the driver, whilst simultaneously providing a tactile indicator to the driver to make the driver turn the wheel I in a clockwise sense.

In other situations it may be more appropriate to actuate the right hand actuator 26 to wake a driver, or even to actuate both actuators 25,26. In some cases it may be appropriate for the control unit 9 to provide pulsed electrical current to either of the actuators 25,26 to alter the dimensions of the rim 12 repeatedly, to provide a more noticeable alert signal to the driver.

In alternative embodiments of the invention the monitoring arrangements 3 incorporates a detection arrangement, such as a camera, which is mounted to the exterior of the vehicle to detect an impending hazard. Such an exterior detection arrangement may be configured to detect if the vehicle is veering out from one side of the lane in which it is being driven, and/or the detection arrangement may be configured to detect a pedestrian crossing, or about to cross, the street in front of the vehicle.

It is to be understood that in some embodiments the rim 12 of the steering wheel I may be covered by a deformable cover, such as a leather skin, to make the rim 12 comfortable to hold. In such embodiments, the moveable element within the rim 12 is moveable so as to deform the cover to distort the cover and alter the dimensions of the rim 12 as described above.

In other embodiments, the rim 12 may be provided with a cover which does not extend over the outer edge of the moveable element, and in such embodiments the outer edge of the moveable element may itself form an outer surface of the rim 12. For instance, in an embodiment such as this the moveable element may form a decorative edge on part of the rim 12.

The embodiments described thusfar have each incorporates a moveable element which is configured to move outwardly from the outer edge of the rim 12. However, in alternative embodiments, the moveable element may be situated anywhere within the rim 12, so as to be able to alter the dimensions of at least a section of the rim 12. For instance, in one embodiment, the moveable element may be positioned on the front edge of the rim 12, facing the driver, so as to move in a direction generally towards the driver.

The embodiments described thusfar have each incorporated one or more actuators in the form of a solenoid actuator. However, in further embodiments, the or each actuator may be in the form of a hydraulic actuator.

In such embodiments, the or each actuator is configured to receive a pressurised fluid, with the or each actuator moving the or each moveable element upon receipt of the pressurised fluid. In such embodiments, the actuator could be in the form of a tube constructed of an elastically deformable material, which expands when a pressurised fluid is injected into the tube. In this embodiment, the control unit 9 has a pump which is adapted to provide the pressurised fluid to the actuator in response to a signal from the processor 8.

When used in this specification and claims, the terms "comprises" and "comprising and variations thereof mean that the specified features, steps or integers are included. The terms are not to be interpreted to exclude the presence of other features, steps or components.

The features disclosed in the foregoing description, or the following claims, or the accompanying drawings, expressed in their specific forms or in terms of a means for performing the disclosed function, or a method or process for attaining the disclosed result, as appropriate, may, separately, or in any combination of such features, be utilised for realising the invention in diverse forms thereof.

Claims

Claims 1. A steering wheel having a rim, the steering wheel incorporating

a system operable to alter the dimensions of at least a section of the rim in response to a predetermined signal, to provide an alert signal to a driver using the wheel.
2. A steering wheel according to Claim 1, wherein the system operable to alter the dimensions of at least a section of the rim comprises at least one movable element which is moveably mounted within the rim, and at least one actuator, the or each actuator being adapted to move the or each said moveable element outwardly from the rim in response to the said predetermined signal to alter the dimensions of a section of the rim.
3. A steering wheel according to Claim 2, wherein the rim comprises one moveable element in the form of a resilient split ring, the split ring having a cutaway section which defines two ends between which a said actuator is mounted, the actuator acting upon at least one of the said ends of the cutaway section in response to the said predetermined signal, to deform the split ring, so that the split ring alters the dimension of at least a section of the rim.
4. A steering wheel according to claim 2, wherein the rim comprises at least two discrete moveable elements, with each said moveable element being adapted to be moved by a respective actuator in response to the said predetermined signal.
5. A steering wheel according to any of Claims 2 to 4, wherein the or each actuator comprises a solenoid having a moveable core, the or each actuator being actuated by an electrical current being supplied to the solenoid to move the core, with movement of the core resulting in movement of the or each said moveable element.
6. A steering wheel according to any one Claims 2 to 4, wherein the or each actuator is a hydraulic actuator which is adapted to move the or each said moveable element when a pressurised fluid is supplied to the or each hydraulic actuator in response to a predetermined signal.
7. A steering wheel according to any one of Claims 2 to 6, wherein at least a part of the surface of the at least one moveable element forms at least part of an outer surface of the rim.
8. A steering wheel according to any one of the preceding Claims, wherein the rim is at least partly covered by a deformable cover, with the deformable cover being deformable when the system alters the dimensions of at least a section of the rim in response to the predetermined signal.
9. A vehicle incorporating the steering wheel of any of the preceding Claims, wherein the vehicle further incorporating a monitor arrangement for monitoring the driver of the vehicle, and a control unit, the control unit being adapted to provide the said predetermined signal to the system to alter the dimensions of at least part of the rim in response to a signal from the monitor arrangement which is indicative of the driver being tired.
10. A vehicle according to Claim 9, wherein the control unit provides the said predetermined signal in response to the driver being tired, and in response to a sensed parameter corresponding to an impending hazard, with the dimensions of a predetermined section of the rim being altered to alert a driver using the wheel, to influence the driver into turning the wheel in a predetermined direction, to steer the vehicle away from the hazard.
11. A steering wheel substantially as herein described with reference to and as shown in Figures 1 to 6 of the accompanying drawings.
12. A steering wheel substantially as herein described with reference to and as shown in Figures 6 and 7 of the accompanying drawings.
13. Any novel feature or combination of features disclosed herein.