SURFACE CHARACTERISTICS

TECHNICAL FIELD

The present invention relates to a method for adaptation of a vehicle's pace to running surface characteristics. The invention relates also to a computer programme product comprising programme code for a computer for implementing a method according to the invention. The invention relates also to a system for adaptation of a vehicle's pace to running surface characteristics, and a motor vehicle equipped with the device.

BACKROUND

Certain vehicles are sometimes used on poor roads, e.g. in forests, in mines or on bad roads where parts of the roadway comprise cavities or unevennesses. There is great risk that parts of a vehicle travelling on a poor road may fail because of the forces to which the vehicle is subject, resulting in costs in terms of maintenance and repair time.

A driver may well also experience discomfort when the vehicle is travelling on a poor road.

GB 2445836, US8050839, DE102008042550 describe various methods for detecting a bad road. SUMMARY OF THE INVENTION

One object of the present invention is to propose a novel and advantageous method for adaptation of a vehicle's pace to running surface characteristics.

Another object of the present invention is to propose a novel and advantageous system and a novel and advantageous computer programme for adaptation of a vehicle's pace to running surface characteristics. A further object of the present invention is to propose a method, a system and a computer programme for achieving reliable adaptation of a vehicle's pace to running surface characteristics.

Certain objects are achieved with a method for adaptation of a vehicle's pace to running surface characteristics according to claim 1 . Other objects are achieved with a system according to claim 14. Advantageous embodiments are indicated in the dependent claims.

One aspect of the present invention is a proposed method for adaptation of a vehicle's pace to running surface characteristics, comprising the steps of

- monitoring a roadway structure, and

- adopting on the basis of the roadway structure thus monitored at least one measure for adaptation of the vehicle's pace. When its pace is adapted to a roadway structure monitored, the vehicle is protected from being subject to forces which might cause parts of it to fail or become worn in an undesirable way. This may involve its speed being lowered to a level appropriate to the unevennesses of the roadway. In one example the vehicle's speed may instead be increased in order to subject it to as small forces as possible. Increasing the speed may be appropriate where the type of roadway structure is such that a higher speed causes the vehicle to ride over unevennesses. One aspect of the present invention is a proposed method for adaptation of a vehicle's pace to running surface characteristics, in which the roadway structure thus monitored serves as a basis for roadway structure classification in terms of unevenness of the roadway.

Classifying the roadway structure makes it possible to achieve precise control of the vehicle's pace by adapting it in such a way that the vehicle is not subject to large forces, while at the same time its pace is adapted so that the loss of time becomes as little as possible.

One aspect of the present invention is a proposed method for adaptation of a vehicle's pace to running surface characteristics, in which said at least one measure comprises at least one of the following:

- delivering warning signals to the vehicle's operator,

- reducing the vehicle's speed,

- increasing the vehicle's speed.

In one embodiment the driver receives a warning signal if the vehicle is travelling at unsuitable speed. In one embodiment the driver receives directives about the speed to be maintained. In another embodiment the vehicle's speed is reduced automatically to a predetermined level. In one embodiment the vehicle's speed is increased automatically to a predetermined level.

This control of speed may be achieved by limiting the engine's maximum available torque. The speed control may in one embodiment cause an automatic gearbox to change down to a predetermined gear which allows a predetermined maximum speed. In one embodiment a braking torque may be applied to the vehicle by its brake system. One aspect of the present invention is a proposed method for adaptation of a vehicle's pace to running surface characteristics, in which said at least one measure is related to the roadway structure classification thus made. One aspect of the present invention is a proposed method for adaptation of a vehicle's pace to running surface characteristics, in which said at least one measure is related both to the roadway structure classification thus made and to the vehicle's speed. In one embodiment the method according to the invention is activated when the vehicle travels at or above a predetermined speed.

In one embodiment the method according to the invention is activated when the vehicle travels at or below a predetermined speed.

In one embodiment the measure adopted is related to vehicle speed and to roadway structure classification. This means that a measure is only adopted when the vehicle's speed is unsuited to the roadway structure's classification. One aspect of the present invention is a proposed method for adaptation of a vehicle's pace to running surface characteristics, in which the roadway structure is continuously monitored by at least one device for detection of angle deflections in the vehicle's steering system. One aspect of the present invention is a proposed method for adaptation of a vehicle's pace to running surface characteristics, in which the roadway structure is intermittently monitored by at least one device for detection of angle deflections in the vehicle's steering system. A device for detection of angle deflections, a steering wheel angle sensor, is installed in certain vehicles. This device is used in a so-called ESP (electronic stability programme) system in order inter alia to prevent skidding. Using this device also for continuous or intermittent monitoring of a roadway structure does not entail having to install extra devices to receive information about the roadway structure. The result is a cost-effective system. One aspect of the present invention is a proposed method for adaptation of a vehicle's pace to running surface characteristics, in which the roadway structure is continuously monitored by at least one device for detection of force deflections in the vehicle's steering system. One aspect of the present invention is a proposed method for adaptation of a vehicle's pace to running surface characteristics, in which the roadway structure is intermittently monitored by at least one device for detection of force deflections in the vehicle's steering system. One aspect of the present invention is a proposed method for adaptation of a vehicle's pace to running surface characteristics, in which the roadway structure is continuously monitored by at least one device for detection of torque in the vehicle's steering system. One aspect of the present invention is a proposed method for adaptation of a vehicle's pace to running surface characteristics, in which the roadway structure is intermittently monitored by at least one device for detection of torque in the vehicle's steering system. One aspect of the present invention is a proposed method for adaptation of a vehicle's pace to running surface characteristics, in which the roadway structure is continuously monitored by at least one accelerometer device for monitoring of vehicle movements, e.g vibrations. One aspect of the present invention is a proposed method for adaptation of a vehicle's pace to running surface characteristics, in which the roadway structure is continuously monitored by at least one distance sensor for detection of vehicle movements.

One aspect of the present invention is a proposed method for adaptation of a vehicle's pace to running surface characteristics, in which the roadway structure is intermittently monitored by at least one distance sensor for detection of vehicle movements.

One aspect of the present invention is a proposed method for adaptation of a vehicle's pace to running surface characteristics, in which the roadway structure is continuously monitored by vibration monitoring means for detection of vibrations of the vehicle's shock-absorber arrangements.

One aspect of the present invention is a proposed method for adaptation of a vehicle's pace to running surface characteristics, in which the roadway structure is intermittently monitored by vibration monitoring means for detection of vibrations of the vehicle's shock-absorber arrangements.

One aspect of the present invention is a proposed method for adaptation of a vehicle's pace to running surface characteristics, in which the roadway structure is continuously monitored by a fuel level sensor in the form of changes in fuel level in the vehicle's fuel container.

One aspect of the present invention is a proposed method for adaptation of a vehicle's pace to running surface characteristics, in which the roadway structure is intermittently monitored by a fuel level sensor in the form of changes in fuel level in the vehicle's fuel container.

One aspect of the present invention is a proposed method for adaptation of a vehicle's pace to running surface characteristics, in which the specific roadway's structure thus monitored is reported externally for recording. External reporting of the roadway structure monitored makes it possible for a vehicle to use this information and reduce its speed when approaching a section of road which requires a low speed. External reporting of the roadway structure monitored makes it possible for a vehicle to use this information and increase its speed when approaching a section of road which requires a high speed.

The method may be implemented in existing motor vehicles. Programme code for adaptation of a vehicle's pace to running surface characteristics according to the invention may be installed in a control unit of the vehicle during the manufacture of the vehicle. A purchaser of the vehicle may thus have the possibility of selecting the function of the method as an option. Alternatively, programme code comprising programme code for conducting the innovative method for adaptation of a vehicle's pace to running surface characteristics may be installed in a control unit of the vehicle on the occasion of upgrading at a service station, in which case the programme code may be loaded into a memory in the control unit. Programme code for adaptation of a vehicle's pace to running surface characteristics may be updated or replaced. Moreover, different parts of the programme code for troubleshooting a system for adaptation of a vehicle's pace to running surface characteristics may be replaced independently of one another. This modular configuration is advantageous from a maintenance perspective.

One aspect of the present invention is a proposed system for adaptation of a vehicle's pace to running surface characteristics, comprising

- means for monitoring a roadway structure, and

- means for adopting on the basis of the roadway structure thus monitored at least one measure for adaptation of the vehicle's pace. The system may comprise

- means for classifying the roadway structure in terms of roadway unevenness on the basis of the roadway structure thus monitored. The system may comprise at least one of the following:

- means for delivering warning signals to the vehicle's operator,

- means for reducing the vehicle's speed,

- means for increasing the vehicle's speed. The system may comprise

- means for continuous monitoring of roadway structure by detection of angle deflections in the vehicle's steering system.

The system may comprise

- means for continuous monitoring of roadway structure by detection of force deflections in the vehicle's steering system.

The system may comprise

- means for intermittent monitoring of roadway structure by detection of force deflections in the vehicle's steering system.

The system may comprise

- means for continuous monitoring of roadway structure by detection of torque in the vehicle's steering system.

The system may comprise

- means for intermittent monitoring of roadway structure by detection of torque in the vehicle's steering system. The system may comprise

- at least one accelerometer device for continuous monitoring of roadway structure by detection of vehicle movements. The system may comprise

- at least one accelerometer device for intermittent monitoring of roadway structure by detection of vehicle movements.

The system may comprise

- at least one distance sensor for continuous monitoring of roadway structure by detection of vehicle movements. The system may comprise

- at least one distance sensor for intermittent monitoring of roadway structure by detection of vehicle movements.

The system may comprise

- at least one vibration monitoring means for continuous detection of vibrations of the vehicle's shock-absorber arrangements.

The system may comprise

- at least one vibration monitoring means for intermittent detection of vibrations of the vehicle's shock-absorber arrangements.

The system may comprise

- at least one fuel level sensor for continuous monitoring of changes in fuel level in the vehicle's fuel container.

The system may comprise

- at least one fuel level sensor for intermittent monitoring of changes in fuel level in the vehicle's fuel container. The system may comprise

- means for externally reporting for recording purposes the roadway structure monitored. The above objects are also achieved with a motor vehicle provided with the system for adaptation of a vehicle's pace to running surface characteristics. The vehicle may be a truck, bus or car.

One aspect of the invention is a proposed computer programme for adaptation of a vehicle's pace to running surface characteristics, which programme comprises programme code for causing an electronic control unit or another computer connected to the electronic control unit to perform steps according to any one of claims 1 -13.

One aspect of the invention is a proposed computer programme for adaptation of a vehicle's pace to running surface characteristics, which programme comprises programme code stored on a computer-readable medium for causing an electronic control unit or another computer connected to the electronic control unit to perform steps according to any one of claims 1 -13.

One aspect of the invention is a proposed computer programme product which comprises a programme code stored on a computer-readable medium for performing method steps according to any one of claims 1 -13 when said programme code is run on an electronic control unit or another computer connected to the electronic control unit. Further objects, advantages and novel features of the present invention will become apparent to one skilled in the art from the following details, and also by putting the invention into practice. Whereas the invention is described below, it should be noted that it is not confined to the specific details described. One skilled in the art having access to the teachings herein will recognise further applications, modifications and incorporations in other fields, which are within the scope of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

For fuller understanding of the present invention and its further objects and advantages, the detailed description set out below should be read in conjunction with the accompanying drawings, in which the same reference notations are used for similar items in the various diagrams, and

Figure 1 illustrates schematically a vehicle according to an embodiment of the invention;

Figure 2 illustrates schematically a system for adaptation of a vehicle's pace to running surface characteristics, according to an embodiment of the invention;

Figure 3a illustrates schematically a steering system according to an embodiment of the invention;

Figure 3b illustrates schematically a steering system according to an embodiment of the invention;

Figure 3c illustrates schematically a steering system according to an embodiment of the invention;

Figure 4 is a schematic diagram illustrating an embodiment of the invention. Figure 5a is a schematic flowchart illustrating a method according to an embodiment of the invention;

Figure 5b is a more detailed schematic flowchart illustrating a method according to an aspect of the invention; and

Figure 6 illustrates schematically a computer according to an embodiment of the invention.

DETAILED DESCRIPTION OF THE DRAWINGS

Figure 1 depicts a side view of a vehicle 100. The vehicle exemplified comprises a tractor unit 1 10 and a semitrailer 1 12. The vehicle may be a heavy vehicle, e.g. a truck or a bus. It may alternatively be a car. The term "link" refers herein to a communication link which may be a physical line such as an opto-electronic communication line, or a non-physical line such as a wireless connection, e.g. a radio link or microwave link. Figure 2 depicts a system 299 of the vehicle 1 00. The system 299 may be situated in the tractor unit 1 10 and may form part of a system for adaptation of a vehicle's pace to running surface characteristics or comprise a system for adaptation of a vehicle's pace to running surface characteristics. The system comprises a first control unit 200 and a second control unit 210.

The system may comprise a means 220 for detection of angle deflections in the vehicle's steering system. Said means 220 is arranged for communication with the first control unit via a link L220. Said means 220 is arranged to continuously or intermittently detect angle deflections in the vehicle's steering system and send to the first control unit 200 via the link L220 signals S220 which contain information about said angle deflections detected. The system may comprise a means 230 for detection of force deflections in the vehicle's steering system. Said means 230 is arranged for communication with the first control unit via a link L230. Said means 230 is arranged to continuously or intermittently detect force deflections in the vehicle's steering system and send to the first control unit 200 via the link L230 signals S230 which contain information about said force deflections detected.

The system may comprise a means 240 for detection of torque deflections in the vehicle's steering system. Said means 240 is arranged for communication with the first control unit via a link L240. Said means 240 is arranged to continuously or intermittently detect torque deflections in the vehicle's steering system and send to the first control unit 200 via the link L240 signals S240 which contain information about said torque deflections detected.

The system may comprise an accelerometer device 250 for monitoring of vehicle movements. Said accelerometer device is arranged for communication with the first control unit 200 via a link L250. Said accelerometer device may be situated at various locations on board a vehicle. In one embodiment it is situated on an axle beam. In one embodiment it is situated on the vehicle's chassis. In one embodiment it is situated on the vehicle's cab. Said accelerometer device is arranged to continuously or intermittently detect accelerations in different directions of the vehicle and send to the first control unit 200 via the link 250 signals L250 which contain information about said accelerations detected. The system may comprise a distance sensor 260 for detection of vehicle movements. Said sensor 260 is arranged for communication with the first control unit 200 via a link L260. Said sensor may be situated at various locations on board a vehicle. In one embodiment said sensor is situated on an axle beam and detects continuously the distance between the axle beam and the chassis. In one embodiment said sensor is situated on the vehicle's chassis. In one embodiment it detects continuously the distance between the chassis and the axle beam or alternatively between the chassis and the cab. In one embodiment said sensor is situated on the vehicle's cab and detects continuously or intermittently the distance between the cab and the chassis. Said sensor is arranged to continuously or intermittently detect the distance between different parts of the vehicle and send to the first control unit 200 via the link L260 signals S260 which contain information about said distances detected. The system may comprise a vibration monitoring means 270 for continuously detecting vibrations of the vehicle's shock-absorber arrangements. Said means 270 is arranged for communication with the first control unit 200 via a link L270. Said means 270 may be situated on a shock-absorber of the vehicle. It is arranged to continuously or intermittently detect vibrations of the vehicle's shock-absorber arrangements. It is adapted to continuously or intermittently send to the first control unit 200 via the link L270 signals S270 which contain information about said vibrations detected.

Said vibration monitoring means 270 in one embodiment is a distance sensor which detects the distance between selected vehicle parts. It comprises in one embodiment an accelerometer which detects vehicle movements. Said movements in one embodiment are vibrations of the vehicle. Said movements in one embodiment are movements in a predetermined direction, e.g. perpendicular to the running surface.

The system may comprise a fuel level sensor 280 for continuous monitoring of changes in fuel level in a fuel container of the vehicle 100. Said sensor 280 is arranged for communication with the first control unit 200 via a link L280. Said sensor is situated on the vehicle's fuel container. It is arranged to continuously or intermittently detect changes in fuel level in the vehicle's fuel container and send to the first control unit 200 via the link L280 signals S280 which contain information about said level changes detected.

The system may comprise a unit 290 arranged to deliver warning signals to an operator. Said unit 290 is arranged for communication with the first control unit 200 via a link L290. Said unit may in one embodiment comprise a lamp. It may in one embodiment comprise a loudspeaker.

In one version the first control unit 200 and/or the second control unit 210 are arranged to classify roadway structure in terms of roadway unevenness. This may be effected by means of a stored calculation model. In one embodiment the roadway structure may be classified in five different classes. In one embodiment it may be classified in two different classes. In one embodiment it may be classified in 1 -20 different classes. The first control unit 200 and/or the second control unit 210 may be arranged to classify said roadway structure on the basis of said angle deflections detected in the vehicle's steering system.

The first control unit 200 and/or the second control unit 210 may be arranged to classify said roadway structure on the basis of said force deflections detected in the vehicle's steering system. The first control unit 200 and/or the second control unit 210 may be arranged to classify said roadway structure on the basis of said torque detected in the vehicle's steering system.

The first control unit 200 and/or the second control unit 210 may be arranged to classify said roadway structure on the basis of vehicle movements monitored by at least one accelerator device 250.

The first control unit 200 and/or the second control unit 210 may be arranged to classify said roadway structure on the basis of vehicle movements monitored by at least one distance sensor 260.

The first control unit 200 and/or the second control unit 210 may be arranged to classify said roadway structure on the basis of vehicle movements monitored by at least one vibration monitoring means 270 for detection of vibrations of the vehicle's shock-absorber arrangements.

The first control unit 200 and/or the second control unit 210 may be arranged to classify said roadway structure on the basis of vehicle movements monitored by a fuel level sensor 280 for detection of changes in fuel level in the vehicle's fuel container. Said classification may be based on at least one of the abovementioned parameters.

The first control unit 200 is arranged to adapt a vehicle's pace to running surface characteristics, comprising the steps of

- monitoring a roadway structure, and

- adopting on the basis of the roadway structure thus monitored at least one measure for adaptation of the vehicle's pace. The first control unit 200 is arranged to adapt a vehicle's pace to running surface characteristics, using the roadway structure thus monitored as a basis for roadway structure classification in terms of roadway unevenness.

The first control unit 200 in one example is arranged to automatically adapt a vehicle's pace to running surface characteristics, using the roadway structure thus monitored as a basis for roadway structure classification in terms of roadway unevenness.

The first control unit 200 is arranged to adapt a vehicle's pace to running surface characteristics, said at least one measure comprising at least one of the following:

- delivering warning signals to the vehicle's operator,

- reducing the vehicle's speed,

- increasing the vehicle's speed.

The first control unit 200 may be arranged to automatically adapt a vehicle's pace to running surface characteristics, said at least one measure comprising at least one of the following:

- delivering warning signals to the vehicle's operator,

- automatically reducing the vehicle's speed,

- automatically increasing the vehicle's speed. The first control unit 200 is arranged to adapt a vehicle's pace to running surface characteristics, said at least one measure being related to the roadway structure classification thus made. In one version the first control unit 200 and/or the second control unit 210 are arranged to send a signal S290 to a unit 290 when the roadway has been placed in a certain predetermined class. Said signal S290 may in one embodiment cause the unit 290 to emit a warning in the form of an acoustic signal. Said signal S290 may in one embodiment cause the unit 290 to emit a light. In one embodiment said signal S290 may cause the unit to emit a flashing light.

In one version the first control unit 200 and/or the second control unit 210 are arranged, where the roadway has been placed in a certain predetermined class, to automatically lower the vehicle's speed to a predetermined level suited to the roadway structure. Said lowering may be effected by the first control unit and/or the second control unit limiting the engine's maximum available torque. It may be effected by the control unit 200, 210 causing the gearbox to adopt a predetermined gear which allows a predetermined maximum speed suited to the roadway structure monitored. In one embodiment the control unit 200, 210 may cause a braking torque to be applied to the vehicle's brakes.

The first control unit 200 is arranged to adapt a vehicle's pace to running surface characteristics, said at least one measure being related both to the roadway structure classification thus made and to the vehicle's speed.

In one embodiment a measure for adaptation of the vehicle's pace is only adopted when the vehicle exceeds a predetermined speed.

The first control unit 200 is arranged to adapt a vehicle's pace to running surface characteristics, the roadway structure being continuously or intermittently monitored by at least one device for detection of angle deflections in the vehicle's steering system.

Monitoring the roadway structure may entail the structure being calculated on the basis of a parameter detected which may for example comprise angle deflections in the vehicle's steering system. In one embodiment the roadway structure may be modelled from or be estimated on the basis of the parameter detected. These various embodiments fall within the concept of monitoring the roadway structure.

The first control unit 200 is arranged to adapt a vehicle's pace to running surface characteristics, the roadway structure being continuously or intermittently monitored by at least one device for detection of steering wheel deflection.

The first control unit 200 is arranged to adapt a vehicle's pace to running surface characteristics, the roadway structure being continuously or intermittently monitored by at least one device for detection of force deflections in the vehicle's steering system.

The first control unit 200 is arranged to adapt a vehicle's pace to running surface characteristics, the roadway structure being continuously or intermittently monitored by at least one device for detection of torque in the vehicle's steering system.

The first control unit 200 is arranged to adapt a vehicle's pace to running surface characteristics, the roadway structure being continuously or intermittently monitored by at least one accelerator device for detection of vehicle's movements.

The first control unit 200 is arranged to adapt a vehicle's pace to running surface characteristics, the roadway structure being continuously or intermittently monitored by at least a distance sensor for detection of vehicle's movements.

The first control unit 200 is arranged to adapt a vehicle's pace to running surface characteristics, the roadway structure being continuously or intermittently monitored by vibration monitoring means for detection of vibrations of the vehicle's shock-absorber arrangements.

The first control unit 200 is arranged to adapt a vehicle's pace to running surface characteristics, the roadway structure being continuously or intermittently monitored by a fuel level sensor in the form of changes in fuel level in the vehicle's fuel container.

The first control unit 200 is arranged to adapt a vehicle's pace to running surface characteristics, the specific roadway's structure thus monitored being reported externally for recording.

The first control unit 200 is arranged for communication with presentation means 400 via a link L400. Said means 400 may already be situated in a driving cab of the vehicle 1 00. Said means may be fitted permanently in the vehicle. Said means may be a mobile electronic unit. Said means may for example comprise a viewing screen.

The first control unit 200 is adapted to using said presentation means 400 to present a measure pertaining to the method according to the invention for adaptation of a vehicle's pace to running surface characteristics. The first control unit is adapted to sending to said presentation means 400 via said link L400 a signal S400 which contains information about said measure. The first control unit 200 is arranged for communication with a communication unit 410 via a link L410. The location of said communication unit may for example be a service station, workshop, haulage operator or a so-called fleet management system.

Said communication unit 410 may be situated in a driving cab of the vehicle 100. It may be permanently fitted in the vehicle. It may be a mobile electronic unit. It may for example comprise a keyboard, button set or a touchscreen. The first control unit 200 may be arranged to be controlled via said communication terminal 410. In one embodiment the method according to the invention is initiated via said communication terminal. In one embodiment the method according to the invention is ended via said communication terminal. Said communication terminal is adapted to generating and sending, on the basis of manual input of information, to the first control unit via said link L410 a signal S410 which contains for example information about initiating or ending the method according to the invention.

A second control unit 210 is arranged for communication with the first control unit 200 via a link L210. This second control unit may be detachably connected to the first control unit. It may be situated externally to the vehicle 100. It may be arranged to conduct the innovative method steps according to the invention. It may be used to crossload software to the first control unit, particularly software for conducting the innovative method. It may alternatively be arranged for communication with the first control unit via an internal network on board the vehicle. It may be adapted to performing substantially similar functions to the first control unit, such as

- monitoring a roadway structure,

- adopting on the basis of the roadway structure thus monitored at least one measure for adaptation of the vehicle's pace.

Figure 3a illustrates schematically a steering system 399 according to an embodiment of the invention. Said system comprises a steering wheel 499, a first link element 101 , a steering gear 300, a second link element 201 , a first wheel spindle 310, a third link element 301 and a second wheel spindle 320. Said system 399 connects said steering wheel 499 to the vehicle's wheels (not depicted). Said first link 101 is also called a steering column. Said second link 201 is also called a draglink. Said third link 301 is also called a track rod. In one embodiment a means 220 for continuous or intermittent monitoring of roadway structure by detection of angle deflections is situated on the upper steering column 101. In one embodiment it is situated on the output shaft of the steering gear 300. In one embodiment it is situated on said first wheel spindle 310. In one embodiment it is situated on said second wheel spindle 320.

Certain vehicles have more links and wheel spindles than the example illustrated in Figure 3a. In such cases, sensors are provided at corresponding appropriate locations. These vehicles are also covered by the method according to the invention.

Figure 3b illustrates schematically a steering system 399 according to an embodiment of the invention. Said system comprises a steering wheel 499, a first link element 101 , a steering gear 300, a second link element 201 , a first wheel spindle 310, a third link element 301 and a second wheel spindle 320. In one embodiment a means 230 for continuous or intermittent monitoring of roadway structure by detection of force deflections is situated on said second link element 201 . In one embodiment said means 230 is situated on said third link element 301 . Figure 3c illustrates schematically a steering system 399 according to an embodiment of the invention. Said system comprises a steering wheel 499, a first link element 101 , a steering gear 300, a second link element 201 , a first wheel spindle 310, a third link element 301 and a second wheel spindle 320. In one embodiment a means 240 for continuous or intermittent monitoring of roadway structure by detection of torque is situated on said first link element 101 . In one embodiment said means 240 is situated on the steering gear 300. Figure 4 is a schematic diagram illustrating an embodiment of the invention, showing the amplitude A on the y-axis as a function of time on the x-axis. The curve depicted might be recorded by any of said means/sensors 220, 230, 240, 250, 260, 270, 280. In this embodiment the roadway structure is placed in a predetermined class, class 2, when the amplitude over a certain predetermined period of time Tset exceeds a predetermined value Ath. In one embodiment the roadway structure is placed in a predetermined class when the amplitude over a certain predetermined period of time Tset exceeds a predetermined value Ath a predetermined number of times.

Said period Tset and said predetermined value Ath may be adapted to which parameter is detected and where the sensor recording it is situated. Said period Tset and said predetermined value Ath may be adapted to the speed at which the vehicle is travelling.

One embodiment takes into the account the frequency of the curve recorded, i.e. number of peaks and troughs over a certain period Tset. When this number exceeds a predetermined value, the roadway structure is placed in a predetermined class.

One embodiment takes into account as a first step the amplitude within a certain predetermined period Tset of a curve recorded. When the amplitude exceeds a predetermined value Ath a predetermined number of times, said curve is analysed within said period Tset with respect to frequency. The roadway structure is placed in a predetermined class with respect to the amplitude and frequency of the curve.

One embodiment takes into account as a first step the frequency within a certain predetermined period Tset of a curve recorded. When the frequency, i.e. the number of peaks and troughs over said period Tset, exceeds a predetermined value Ath, said curve is analysed within said period Tset with respect to the amplitude A. The roadway structure is placed in a predetermined class with respect to the frequency and amplitude of the curve. In another embodiment the roadway structure may be placed in two or more different classes.

In one embodiment, classification is based on at least one of said parameters, e.g. angle deflections. In one embodiment it is based on more than one of said parameters. The classification for each individual parameter is taken into account in determining an overall classification for the roadway structure.

In one embodiment the roadway structure's class decides which measure should be adopted.

In one embodiment the roadway structure's class and the vehicle's speed decide which measure should be adopted. Figure 5a is a schematic flowchart of a method for adaptation of a vehicle's pace to running surface characteristics, comprising a first step s501 of

- monitoring a roadway structure, and

- adopting on the basis of the roadway structure thus monitored at least one measure for adaptation of the vehicle's pace.

The method ends after step s501 .

Figure 5b is a schematic flowchart of part of a method for adaptation of a vehicle's pace to running surface characteristics. The method comprises a step s510 of continuous monitoring of parameters which depend on the roadway structure. The method further comprises a step s520 of assessing said parameters.

The method further comprises a step s530 of classifying the roadway structure.

The method further comprises a step s540 of determining a measure. Said measure may be related to the roadway structure classification made. It may be related to the roadway structure classification made and to the vehicle's speed.

The method further comprises a step s550 of effecting said measure determined.

The method ends after step s550.

Figure 6 is a diagram of a version of a device 600. The control units 200 and 210 described with reference to Figure 2 may in one version comprise the device 600. The device 600 comprises a non-volatile memory 620, a data processing unit 610 and a read/write memory 660. The non-volatile memory 620 has a first memory element 630 in which a computer programme, e.g. an operating system, is stored for controlling the function of the device 600. The device 600 further comprises a bus controller, a serial communication port, I/O means, an A/D converter, a time and date input and transfer unit, an event counter and an interruption controller (not depicted). The non-volatile memory 620 has also a second memory element 640.

A proposed computer programme P may comprise routines for adaptation of a vehicle's pace to running surface characteristics. The computer programme P may comprise routines for adaptation of a vehicle's pace to running surface characteristics, comprising the steps of - monitoring a roadway structure, and - adopting on the basis of the roadway structure thus monitored at least one measure for adaptation of the vehicle's pace.

The computer programme P may comprise routines for adaptation of a vehicle's pace to running surface characteristics, using the roadway structure thus monitored as a basis for roadway structure classification in terms of roadway unevenness.

The computer programme P may comprise routines for adaptation of a vehicle's pace to running surface characteristics, said at least one measure comprising at least one of the following:

- delivering warning signals to the vehicle's operator,

- reducing the vehicle's speed,

- increasing the vehicle's speed.

The computer programme P may comprise routines for adaptation of a vehicle's pace to running surface characteristics, said at least one measure being related to the roadway structure classification thus made. The computer programme P may comprise routines for adaptation of a vehicle's pace to running surface characteristics, said at least one measure being related both to the roadway structure classification thus made and to the vehicle's speed. The computer programme P may comprise routines for adaptation of a vehicle's pace to running surface characteristics, the roadway structure being continuously monitored by at least one device for detection of angle deflections in the vehicle's steering system. The computer programme P may comprise routines for adaptation of a vehicle's pace to running surface characteristics, the roadway structure being continuously or intermittently monitored by at least one device for detection of force deflections in the vehicle's steering system.

The computer programme P may comprise routines for adaptation of a vehicle's pace to running surface characteristics, the roadway structure being or intermittently monitored by at least one device for detection of torque in the vehicle's steering system.

The computer programme P may comprise routines for adaptation of a vehicle's pace to running surface characteristics, the roadway structure being continuously or intermittently monitored by at least one accelerator device for detection of vehicle's movements.

The computer programme P may comprise routines for adaptation of a vehicle's pace to running surface characteristics, the roadway structure being continuously or intermittently monitored by at least a distance sensor for detection of vehicle's movements.

The computer programme P may comprise routines for adaptation of a vehicle's pace to running surface characteristics, the roadway structure being or intermittently monitored by vibration monitoring means for detection of vibrations of the vehicle's shock-absorber arrangements.

The computer programme P may comprise routines for adaptation of a vehicle's pace to running surface characteristics, the roadway structure being continuously or intermittently monitored by a fuel level sensor in the form of changes in fuel level in the vehicle's fuel container.

The computer programme P may comprise routines for adaptation of a vehicle's pace to running surface characteristics, the specific roadway's structure thus monitored being reported externally for recording. The computer programme P may be stored in an executable form or in compressed form in a memory 660 and/or a read/write memory 650.

Where the data processing unit 61 0 is described as performing a certain function, it means that it conducts a certain part of the programme stored in the memory 660 or a certain part of the programme stored in the read/write memory 650.

The data processing device 61 0 can communicate with a data port 699 via a data bus 615. The non-volatile memory 620 is intended for communication with the data processing unit 610 via a data bus 612. The separate memory 660 is intended to communicate with the data processing unit via a data bus 61 1 . The read/write memory 650 is arranged to communicate with the data processing unit via a data bus 614. The data port may for example have the links L210, L220, L230, L240, L250, L260, L270, L280, L290, L400 and L410 connected to it (see Figure 2).

When data are received on the data port 699, they are stored temporarily in the second memory element 640. When input data received have been temporarily stored, the data processing unit 610 is prepared to conduct code execution as described above.

In one version, signals received on the data port 699 contain information about angle deflections in the vehicle's steering system 399. In one version, signals received on the data port contain information about force deflections in the vehicle's steering system 399. In one version, signals received on the data port contain information about torque in the vehicle's steering system 399. In one version, signals received on the data port contain information about vehicle movements detected by at least one accelerometer device 250. In one version, signals S270 received on the data port contain information about vehicle movements detected by at least one distance sensor 260. In one version, signals received on the data port contain information about vehicle movements detected by a vibration monitoring means 270 for continuously or intermittently monitoring of vibrations of the vehicle's shock- absorber arrangements. In one version, signals S280 received on the data port contain information about vehicle movements detected by a fuel level sensor 280 for continuous detection of changes in fuel level in the vehicle's fuel container.

The signals received on the data port 699 may be used by the device 600 to adapt the pace of a vehicle to running surface characteristics. Parts of the methods herein described may be conducted by the device 600 by means of the data processing unit 610 which runs the programme stored in the memory 660 or the read/write memory 650. When the device 600 runs the programme, methods herein described are executed. The foregoing description of the preferred embodiments of the present invention is provided for illustrative and descriptive purposes. It is not intended to be exhaustive, nor to restrict the invention to the variants described. Many modifications and variations will obviously suggest themselves to one skilled in the art. The embodiments have been chosen and described in order best to explain the principles of the invention and their practical applications and thus make it possible for one skilled in the art to understand the invention for different embodiments and with the various modifications appropriate to the intended use.