GB2287231A - Vehicle control system with infra-red or cable link - Google Patents

Abstract

A steering and electrical control device, especially for physically disabled drivers, may have an electrical switch-pad 18 which is mounted on the steering wheel, fig. 1, or a sender unit 50 with a single push button 58, fig. 6, which controls several functions, the desired one being selected according to the length of time during which the button is depressed. Electrical signals are transmitted to the switching unit 54 either directly by cable 56 or, if the switch unit is mounted on the steering wheel, by infra-red to a receiver 52 and thence to the switching unit 54. <IMAGE>

Description

CONTROL SYSTEM FOR MOTOR VEHICLE This invention relates to a control system for a motor vehicle, and to a motor vehicle having such a control system. This invention is particularly, but not exclusively, concerned with assisting physicallydisabled persons to drive.

It is known to provide a control device for a motor vehicle comprising a housing attached adjacent the rim of the steering wheel of the vehicle so that the housing can rotate relative to the steering wheel about an axis parallel to the axis of the steering wheel, a knob projecting from the housing, and a switch-pad mounted on the housing for controlling various functions of the vehicle. A problem which arises with the known device is that one which is designed to "fit", say, a man's broad hand may be difficult to use by a woman with a small frail hand. It might, therefore, be considered appropriate to provide different sized knobs for these devices to deal with this problem, but this still presents difficulties in dealing with different reaches of different people's fingers, and also a supplier of the devices would need to keep in stock a range of different knobs.

In order to deal with this problem, a first aspect of this invention provides a control device which is characterised in that the switch-pad and the knob are adjustable in position relative to each other, preferably in a direction parallel to the axis of rotation.

Thus the device can be adjusted to suit the different reaches of different people's hands.

In a specific embodiment of this first aspect of the invention, the housing has a recess, and the position of the switch-pad is adjustable into and out of the recess. Furthermore, means are preferably provided for locking the switch-pad in position relative to the housing, with a manually-operable release for the locking means.

Conveniently, in order to deal with right- and left-handed drivers, the switch-pad is removable from the housing and replaceable in a different orientation relative to the housing (for example rotated through half a turn).

In a known system of the above-mentioned general type, the control device (now referred to as a remote sender) mounted on the steering wheel transfers wire-less (such as infra-red or ultrasonic) signals to a receiver unit mounted, for example, near the drivers sun visor, which in turn transmits electrical signals to a switching unit to switch functions of the vehicle, such as sounding the horn, toggling operation of the direction indicators, and toggling operation of the windscreen wipers and operating the windscreen washer. If the installation permits, and if greater reliability is required, it might be considered appropriate to mount the remote sender, for example, near the gear-stick and hard-wire connect it to the switching unit, rather than using an infra-red link. However, a supplier of these systems would then need to keep both types of sender in stock, which is inconvenient.

In order to deal with this problem, a second aspect of the present invention provides a system in which the same sender can either be hard-wire linked to the switching unit, or be wire-less linked to a receiver which in turn is hard-wire linked to the switching unit. The receiver can therefore be supplied as an optional extra, but the same sender and the same switching unit can be used in both configurations.

In a known system of the above-mentioned general type in which the sender has, perhaps, only one push-button switch, particular functions of the vehicle are selected in dependence upon the period of time for which the switch is operated, which may be signalled to the driver by a series of audible "beeps".

For example, if the switch is held down for one beep and then released, the horn will sound for 0.5 seconds. Sometimes, the driver may wish such an operation to continue for longer, and in this case in the known system the driver must repeat the operation, which is inconvenient.

In order to deal with this problem, in accordance with a third aspect of the present invention, upon a repeat operation of the switch the selected function is held. Conveniently, an operation of the switch may be classed as such a repeat operation only if it occurs within a predetermined period of time (eg 0.5s) after a preceding operation, and conveniently also an operation of the switch may be classed as such a repeat operation only if it occurs for more than a predetermined period of time (eg 0.5s). Thus, as an example, if the switch is pressed for a count of one, released, pressed again within 0.5s, and held for at least 0.5s, the horn will continue to-sound for so long as the switch remains pressed.

In the known systems, there is control of a predetermined number of functions of the vehicle, for example four in one version, and nine in another version. Considering, say, the nine operation version, if, say, the three-beep operation is the right direction indicator, then there is a problem if the driver loses count of the number of beeps.

If the driver intends signalling right, but realises that he has lost count, then when he does release the switch some unexpected operation will occur, or if he holds the switch until the maximum count of nine and then releases, he will operate, say, the hazard warning lights.

In order to deal with this problem, a fourth aspect of the present invention provides a system in which if the switch is operated for more than a predetermined period of time (such as nine beeps plus 0.5s, in the nine operation version) no function is selected.

As mentioned above, in the known systems, there is control of a predetermined number of functions of the vehicle, for example four in one version, and nine in another version. It is therefore necessary for a manufacturer to make the two different versions and for a supplier to hold stocks of the two different versions, which is inconvenient and inefficient. In order to deal with this problem, it might be considered desirable to provide an additional switch to switch between the two different modes, but this would involve extra hardware costs.

In order to deal with these problems, a fifth aspect of the present invention provides a system which has two modes of operation, and in which the mode of operation is selected in dependence upon whether or not the switch is operated when a replaceable power supply battery is connected to the sender.

As mentioned above, a function may be selected in dependence upon the period of time for which the switch is operated, and the period may be indicated to the user by a series of audible beeps. Occasionally a user may make a mistake by operating the switch for longer than desired, for example for six beeps, instead of a desired five beeps.

Although, in accordance with the above mentioned fourth aspect of the invention, the user can cancel the selection by depressing the switch for longer so as to reset the system, this causes a delay.

In order to deal with this problem, a sixth aspect of the present invention provides a system in which, upon a repeat operation of the switch the period of the preceding operation of the switch is treated as having been shorter. Conveniently, and also so as to enable this aspect of the invention to be used in conjunction with some of the above- and below-mentioned other aspects of the invention, an operation of the switch may be classed as such a repeat operation only if it occurs within a predetermined period of time (for example 0.5s3 after a preceding operation, and only if it occurs for less than a predetermined period of time (for example 0.5s).

In the known systems, there are limits on the number of operations which can be controlled by the system, that is four or nine in the specific cases mentioned above. In some cases, it is desirable to be able to control more operations of the vehicle. However, if, say, a twenty beep version were provided, there would be an inordinate delay in activating the twentieth operation.

In order to deal with this problem, a seventh aspect of the present invention provides a system in which one of a group of functions (such as lights) is selected in dependence upon the period of time for which the switch is operated, and upon a repeat operation of the switch the functions of the selected group are cyclicly selected (for example between side-lights, dipped-beam headlights, main-beam headlights, and lights off). Conveniently, and again also so as to enable this aspect of the invention to be used in conjunction with some of the above-mentioned other aspects of the invention, an operation of the switch may be classed as such a repeat operation only if it occurs within a predetermined period of time (for example 0.5s) after a preceding operation, and only if it occurs for more than a predetermined period of time (for example 0.5s).

It will be appreciated that various combinations of the abovementioned aspects of the invention may be embodied in a single system so as to obtain the combined advantages of those aspects of the invention.

Two embodiments of the present invention will now be described by way of example with reference to the accompanying drawings in which: Figure 1 is a perspective view of a control device in accordance with the first aspect of the present invention; Figure 2 is an end view of the Figure 1 device with the switch pad in one position; Figure 3 is a partial end view of the Figure 1 device with the switch-pad in a different position; Figure 4 is a sectional view through the switch-pad and its housing; Figure 5 is a view on the section line 5-5 in Figure 4; Figure 6 is a view of the layout of a system in accordance with the second to seventh aspects of the present invention; Figure 7 is a block diagram of the circuitry in the sender unit of the Figure 6 system; and Figure 8 is a flow diagram of the operation of the Figure 7 sender unit.

Referring firstly to Figures 1 to 5, a steering and electrical control device 10, in accordance with the first aspect of the present invention, comprises a housing 12 which is fixed by a bracket (not shown) to the rim of a motor car steering wheel for rotation about an axis 14 parallel to the axis of rotation of the steering wheel. The housing 12 has two wings, one 16 of which houses a switch-pad 18, and the other 20 of which acts as a counterbalance. Between the wings 18, 20, a knob 22 projects along the axis 14. By holding the knob 22, a driver can control the steering of the car, and the switch-pad 18 includes a number of switches which are intended to be within the reach of the driver's hand while holding the knob 22.

In order to fit the device to different drivers' hands, the switch-pad 18 is adjustable in position in a direction parallel to the axis 14 between the two positions shown in Figures 2 and 3. Adjustment of the position of the switch-pad 18 is enabled by depressing a pair of buttons 24, 26 on opposed sides of the wing 16 of the housing and pulling or pushing the switches of the switch-pad 18.

Further detail of the adjustment mechanism will now be described with particular reference to Figures 4 and 5. The wing 16 of the housing 12 comprises a peripheral wall 28 and a base plate 30 which is attached beneath the peripheral wall 28 by snap-fit clips (not shown).

The switch-pad 18 is formed by an open-bottomed box having a top 32 and a peripheral wall 34. The peripheral wall 34 of the switch pad 18 is a slide fit within the peripheral wall 28 of the housing wing 16. (In Figure 4, detail of the switches of the switch-pad 18 is not shown, to improve clarity.) Each button 24 (or 26) projects from a respective upstanding tongue 36 which is integrally moulded with the base plate 30. The peripheral wall 34 of the switch pad 18 is sandwiched between the peripheral wall 28 of the housing and the respective tongue 36, and the inner surface of the peripheral wall 34 has a series of serrations 38, with complementary serrations 40 being provided on the outwardly facing surface of the tongue 36. Normally, the serrations 38, 40 engage so as to fix the position of the switch-pad 18. However, if both buttons 24, 26 are depressed, the serrations disengage, and the switch-pad 18 can be adjusted in position. As shown particularly in Figure 5, the peripheral wall 34 of the switch-pad 18 has a cut-out 42 so as not to restrict the movement of the switch-pad 18.

The fitting of the switch-pad 18 into the wing 16 of the housing is symmetrical. Accordingly, the device can be adapted for use by right- and left-hand drivers. This is done by removing the base plate 30 of the housing 12. The switch-pad 18 can then be removed downwardly from the housing 12, turned through half a turn, and then re-inserted into the housing 12, with the base plate 30 then being re-fitted to the housing 12.

Referring now to Figures 6 to 8 of the drawings, a control system in accordance with the second to seventh aspects of the present invention will be described. Referring particularly to Figure 6, in one configuration of the system, it comprises a sender unit 50, a switching unit 54, and a cable 56 interconnecting the sender unit 50 and switching unit 54. This configuration is suitable in the case where the position of the sender unit 50 is fixed, for example adjacent the gear-stick of the vehicle. In another configuration of the system, the system also comprises a receiver unit 52 with which the sender unit 50 communicates with infra-red signals, and the cable 56 interconnects the receiver unit 52 and the switching unit 54. This configuration is suitable when the sender unit 50 is mounted, for example, on the steering wheel, and in this case the receiver unit may be mounted adjacent the sun visor. The sender unit 50 includes a switch operated by a push-button 58, and in response to operation of the button 58 by the driver generates pulse position modulated signals which are transmitted either directly via the cable 56 to the switching unit 54, or indirectly as infra-red signals to the receiver 52 and then as electrical signals via the cable 56 to the switching unit 54. The switching unit 54 includes a number of relays for other switching devices and can switch on and off electrical functions of the vehicle through a bank of connectors 60.

Referring now to Figure 7, the sender unit 50 includes a microcomputer, comprising a micro-processor unit MPU, a random access memory RAM, a read only memory ROM, and an input/output circuit 10. The sender unit 50 also includes a voltage regulator VR which can receive the vehicle's battery voltage via the connector CON and can recharge a replaceable rechargeable battery B. The battery voltage is supplied to the MPU, RAN, ROM and IO. The IO is connected to the switch operated by the push-button 58 so that the MPU can check the state of the switch. The IO also outputs to a signal connection of the connector CON, to an infra-red light-emitting diode IRD, and to a piezo-electric audible beeper device 59.

Figure 8 is a flow diagram showing one example of the operation of the MPU in the sender unit 50. The sender unit 50 is normally powered-on all of the time by the rechargeable battery B. However, when the battery B is replaced, the MPU undergoes a series of initialisation steps 62a, 62b, 62c. In step 62b, the MPU detects whether the button 58 is depressed. If it is, then a four-function mode is selected, whereas if it is not, a nine-function mode is selected. The normal idle state of the routine is at step 64 waiting for the button 58 to be depressed. When the button is depressed, a counter C1 is reset and started, and the beeper 59 is beeped at 0.5s intervals. (In the nine-function mode, the maximum count of the counter C1 is nine, and the maximum number of beeps is also nine.

Conversely, in the four-function mode, the maximum count and the maximum number of beeps are four.) In step 68, the MPU waits for the button 58 to be released. When it is, in step 70, the counter and the beeper are stopped, and in step 72 a second counter C2 is reset and started. Once the counter C2 has reached a count of 1 (after 0.5s) provided in step 74, the MPU then checks in step 76 whether the button is depressed. If not, then in step 78, the function designated by the count C1, as described in more detail below, is performed, and the routine loops back to step 64. If, in step 76, the button is depressed, then in step 80 the MPU resets and starts a counter C3. In step 82, the MPU waits for the counter C3 to reach a count of 1 (after 0.5s), and then in step 84 the MPU detects whether the button 58 is depressed. If not, then in step 86, the count of the counter Cl is decremented by one, and the routine loops back to step 72. If, in step 84, the button is depressed, then in step 88 a "modified" function designated by the count C1 is started. Then, in step 90, the MPU waits for the button to be released, and then in step 92 the modified function is ceased, and the routine loops back to step 64.

The normal and modified functions designated by the various counts of the counter C1 may, in the nine-function mode, be for example as follows: Count Cl Device Normal Function "Modified" Function 0 Nothing Nothing Nothing 1 Horn 0.5 Second blast Hold on 2 Left direction Toggle on/off and As for normal function indicator switch right indicator off 3 Right direction Toggle on/off and As for normal function indicator switch left indicator off 4 Lights Toggle side-lights Cycle: side-lights; on/all lights off dipped-beam; main beam; lights off 5 Flash 0.5 second Hold headlights on headlight flash 6 Front Toggle wiper Cycle: intermittent washer/wiper on/off wipe; slow wipe; fast wipe; wash and wipe; off 7 Rear Toggle wiper Cycle: intermittent washer/wiper on/off wipe; continuous wipe; wash and wipe; off 8 Rear window Toggle on/off As for normal function heater 9 Hazard lights Toggle on/off Nothing For a count C1 equal to one in the table above, it will be noted that, with the modified function, the horn is held on, and for a count C1 equal to five, it will be noted that the modified function is to hold the headlights on. These hold functions, in accordance with the third aspect of the invention mentioned above, are provided by the flow of steps 72 to 76, 80 to 84, and 88 to 92, in the Figure 8 flow diagram.

It will also be noted that, for a count Cl equal to nine, the modified function is to perform nothing. Accordingly, if the button 58 is held after the maximum count, the system resets and no function is selected, in accordance with the fourth aspect of the invention mentioned above.

It will also be noted that, if the button 58 is stabbed for less than 0.5s within 0.5s after it has been released, then the count is decremented by one, in accordance with the sixth aspect of the invention mentioned above. This is provided for by steps 72 to 76 and 80 to 86 in the flow diagram of Figure 8.

From the table above, it will also be noted that if the button 58 is released and then held after a count of four, six or seven, then various functions are cycled, as provided for by the seventh aspect of the invention mentioned above, so that the system can deal with more than nine.

If the four-function mode is selected, by depressing the button 58 when the battery B is connected to the sender unit 50, then the . < PU is programmed to operate according to a simplified form of the table set out above.

It will be appreciated that many modifications and developments may be made to the various aspects of the invention, and the above description and drawings are given only as an example.

Claims (4)

1. A control system for a motor vehicle, comprising: a switching unit responsive to an electrical signal to switch functions of the vehicle; and a remote sender means having at least one manually-operable switch, means for producing an electrical signal in response to operation of the or each switch, means for transmitting the electrical signal to the switching unit, and means for producing a wire-less (such as infra-red or ultrasonic) signal in response to the electrical signal so that alternatively a receiver unit can produce an electrical signal in response to the wire-less signal for supply to the switching unit.

2. A system as claimed in claim 1, further comprising such a receiver unit and means for supplying the electrical signal from the receiver unit to the switching unit.

3. A control system substantially as described with reference to Figures 6 to 8 of the drawings.

4. A motor vehicle having a control system as claimed in any of claims 1 to 3.