TECHNICAL FIELD

The present invention relates to a method for improving the drivability of a motor vehicle. 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 device and a motor vehicle equipped with the device.

BACKGROUND

Vehicles today are controlled automatically by a multiplicity of different parameters and degrees of freedom. A number of different sensors are adapted to providing information to one or more different control units for conducting control on the basis of that information. As an example, fuel injection in a vehicle engine has developed radically over recent years.

Development work to optimise various methods for control of motor vehicles is ongoing.

There is constant need to improve the control of motor vehicles in order in various ways to achieve improved drivability.

US 7,117,075 B1 describes a method for logging and reporting driver activity and vehicle operation, comprising the step of identifying a driver of a vehicle and recording operating data. Operating data are recorded by a device for recording data on board the vehicle, which device is connected to a data bus for an engine control unit of the vehicle and coupled to a distance measuring system which is linked to a GPS system. Information about current time, date and vehicle position is provided by the GPS system. SUMMARY OF THE INVENTION

An object of the present invention is to propose a novel and advantageous method for improving the drivability of a motor vehicle.

Another object of the invention is to propose a method, a device and a computer programme for improving the drivability of a motor vehicle.

A further object of the invention is to propose a method and computer programme for implementing a user-friendly method for improving the drivability of a motor vehicle.

These objects are achieved with a method for improving the drivability of a motor vehicle, which method comprises the steps according to claim 1.

With advantage, improved drivability of a motor vehicle which caters for the legal requirements and climate prevailing in the area where the vehicle is driven is made possible.

Improved drivability may for example take the form of better fuel economy. Improved drivability may for example take the form of lower emissions from the vehicle when in motion. Improved drivability may for example take the form of better overall driving experience for the driver.

The method may comprise the step of manually putting information about the vehicle's location into a tachograph. The term "vehicle's location" means a geographical area within which the vehicle is for the time being. The method may comprise the step of providing current time and date in a tachograph in the vehicle by means of a time recording device.

Controlling the vehicle on the basis of the information about its location which has been put into its tachograph makes it possible for this information to be regarded as correct from a legal perspective, since there are legal requirements that the information in the tachograph has to be correct. A driver of the vehicle who actively puts information in about the area in which the vehicle is situated may therefore be held responsible for the information being correct.

Putting information in manually about the vehicle's location in a given geographical area represents a user-friendly and intuitive method for improving the drivability of the vehicle. Only one input will be necessary for a given area, as the vehicle will be controllable on the basis of that input for as long as it is being driven within that area. A new input of the vehicle's location may possibly be necessary for each new driving shift. A fresh input of information about the vehicle's location needs to be effected in due time after the vehicle has crossed a boundary to another area, e.g. a national frontier, in cases where the respective areas are governed by different legislation.

The information transmitted about current time, date and the vehicle's location makes it possible to use reference values and/or driving modes generated or stored in the control unit for a given vehicle location or time. These reference values include parameter values for regulators and are usable for controlling the vehicle in order to improve its drivability.

Using information from the tachograph makes it possible to reduce the number of further sensors for providing the same information, e.g. a GPS for providing the vehicle's location.

The method may further comprise the steps of:

- associating the information about the vehicle's location with information about legal requirements which apply for the geographical area corresponding to the vehicle's location; and - controlling the vehicle on the basis of the information about legal requirements which apply for the geographical area corresponding to the vehicle's location.

The advantage of this is that the vehicle can be driven in a manner which is optimum as regards legal requirements which apply within the area, e.g. as regards discharge of emissions.

The method may further comprise the steps of calculating a state by using a state model on the basis of the information transmitted from the tachograph about current time, date and the vehicle's location, and of controlling the vehicle on the basis of the calculated state. The state model may be a climate model.

The state may be any from among air humidity, ambient temperature or concentration of a certain substance in the surrounding air.

The step of controlling the vehicle on the basis of the information transmitted from the tachograph may comprise the step of controlling injection of fuel to the vehicle's engine, VGT position, throttle position, urea injection to an SCR catalyst and/or pressure of an exhaust brake.

The step of controlling the vehicle on the basis of the information transmitted from the tachograph comprises the step of controlling the vehicle so that emissions from the vehicle can be adjusted on the basis of legal requirements which apply for the geographical area which pertains to the vehicle's location. The vehicle may therefore be caused to adapt its emissions on the basis of legal requirements for the area in which the vehicle is at the time. Taking into account information about current time, date and the vehicle's location makes it possible for suitably adapted regulator settings or settings of reference values to be used for controlling the vehicle. An advantage of using data from the tachograph already present in the vehicle and of using state models, virtual sensors, regulators etc. stored in the control unit is that no extra sensors, such as a sensor for measuring air content, with associated periphery equipment, are needed to make it possible to improve the drivability of a motor vehicle as regards prevailing legal requirements. A driver of the vehicle can easily use the tachograph to input information about the vehicle's location and thereafter drive the vehicle which will automatically optimise, for example, emission discharges or fuel injection to the engine.

It will be easy for a driver of the vehicle to use the tachograph to input information about the vehicle's location and thereafter drive the vehicle which will automatically optimise after-treatment, including control of, for example, catalysts.

According to an embodiment, the information from the tachograph about the vehicle's location and/or current time and/or current date is used as a basis for indicating suitable intervals for changing of fluids and wearing items such as air filters, fuel filters, oil filters, engine oil and transmission oil.

According to an embodiment, the information from the tachograph about the vehicle's location and/or current time and/or current date can be used to cater for the type of fuel with which the vehicle is refuelled. The quality and content of fuel in different geographical areas may differ. Filling stations in different countries may supply fuel with, for example, different amounts of sulphur content. Using fuels of different quality may cause changes in engine torque and power output. Modelling of fuel quality in the control unit makes it possible to adapt the control of the vehicle. Improved drivability of the vehicle can thus be achieved.

With advantage, the drivability of a vehicle according to a version of the present invention can be improved by controlling the vehicle on the basis of legal requirements and climate within a given area. Improved drivability is achieved in a simple and cost-effective way by taking into account information transmitted from the tachograph to the control unit.

In a vehicle with a tachograph, a driver can achieve desired driving characteristics of the vehicle by input of information about the vehicle's location. These driving characteristics may be particularly desirable in situations where the driver drives the vehicle across boundaries between areas in which different legislation applies, e.g. as regards levels of permissible emission discharges.

Predetermined functionality of the control unit for controlling the vehicle may be activated for an area governed by specific legal requirements. It is thus possible for the behaviour of the motor vehicle to be modified for an area where given legal requirements apply and for the driver of the vehicle to achieve characteristics of the vehicle which are appropriate to driving the vehicle within that specific area.

Providing a method for easily adapting the control of the vehicle on the basis of legal requirements for the area in which the vehicle is situated results in a more versatile scope for use of the vehicle.

The method is easy to implement in existing motor vehicles which have a digital tachograph. Software for improving the drivability of a motor vehicle according to the invention can be installed in a control unit of the vehicle during 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, software which comprises programme code for executing the innovative method for improving the drivability of a motor vehicle may be installed in a control unit of the vehicle on the occasion of upgrading at a service station, in which case the software may be loaded into a memory of the control unit. Implementing the innovative method is therefore inexpensive, particularly as no further knobs, buttons or electronic components need be installed in the vehicle. Necessary hardware is currently already provided in the vehicle. The invention therefore represents a cost-effective solution to the problem of improving the drivability of a motor vehicle.

Software which comprises programme code for improving drivability by controlling the vehicle on the basis of information transmitted from the tachograph to the control unit is easy to update or replace. Different portions of software which comprise programme code for improving the drivability of the motor vehicle can also be replaced independently of one another. This modular configuration is advantageous from a maintenance perspective.

The method according to the invention represents a robust function which provides a driver of the vehicle with greater potential for driving the vehicle in a competitive way, particularly when crossing from an area governed by a first set of legislation to an area governed by a second set of legislation.

The objects indicated above are also achieved with a device for improving the drivability of a motor vehicle, which device comprises the features according to claim 10. Advantageous embodiments are indicated in the dependent claims 10-18.

The tachograph card may contain information about the driver who is driving the vehicle and his/her driving style. Stored settings associated with a specific driver may be activated when driving and affect the control of the vehicle. One or more emission patterns may also be calculated on the basis of that information.

An advantage of the device according to the invention is that a more competitive vehicle can be achieved. Automatic control based on manual input of information into the tachograph makes it possible for the vehicle to be controlled according to the greater or lesser severity of emission legislation in different geographical areas.

The innovative method and device provide greater potential for achieving good fuel consumption and drivability within prevailing legislation.

These objects are also achieved with a motor vehicle which comprises the features according to claim 19. The motor vehicle may be a truck, bus or passenger car.

These objects are also achieved with a computer programme for improving the drivability of a motor vehicle, which computer programme comprises programme code stored on a computer-readable medium in order to cause an electronic control unit or another computer connected to the electronic control unit to perform the steps indicated in claims 1-9.

These objects are also achieved with a computer programme product comprising a programme code stored on a computer-readable medium in order to perform the method steps according to claims 1-9.

Using information from the tachograph card or the tachograph, in combination with an internal memory (of the control unit) which comprises information about various countries' fuels, emission legislation and corresponding engine parameters, makes it possible for the control device to adopt settings according to those requirements and hence achieve improved drivability. Reduction of fuel consumption and lengthening of engine service life can be achieved.

Climate models stored in the control unit may be improved if they can be parameterised/adapted to the region in which they are used. Knowledge of the vehicle's location makes it possible to achieve improved drivability of the vehicle. 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 limited to the specific details described. Specialists who have access to the teachings herein will recognise further applications, modifications and incorporations within other fields, which are within the scope of the invention.

CONCISE DESCRIPTION OF THE DRAWINGS

For a more complete understanding of the present invention and further objects and advantages thereof, the detailed description set out below should be read together with the accompanying drawings, in which the same reference notations denote similar items in the various drawings, and in which:

Figure 1 illustrates schematically a vehicle according to an embodiment of the invention; Figure 2 illustrates schematically a subsystem for the vehicle depicted in

Figure 1 , according to an embodiment of the invention;

Figure 3 illustrates schematically a subsystem for the vehicle depicted in

Figure 1 , according to an embodiment of the invention;

Figure 4 illustrates schematically a flowchart according to an embodiment of the invention; and

Figure 5 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 exemplified vehicle 100 comprises a tractor unit 110 with a trailer 112. The vehicle may be a heavy vehicle, such as a truck or a bus. The vehicle may alternatively be a passenger car. The vehicle 100 is a motor vehicle with automated transmission. In this version the vehicle therefore lacks a conventional clutch pedal and the driver drives the vehicle by means of an acceleration control, e.g. an accelerator pedal, and a means of changing the transmission ratio as indicated below.

The term "link" refers herein to a communication link which may be a physical connection such as an opto-electronic communication line, or a non-physical connection such as a wireless connection, e.g. a radio link or microwave link.

Figure 2 depicts a subsystem 299 of the vehicle 100. The subsystem 299 is arranged in a tractor unit 110. The subsystem 299 has an engine 230. The engine 230 may be a combustion engine. The combustion engine may be an engine with six cylinders. The combustion engine may alternatively have four, five or eight cylinders. The combustion engine may be a diesel engine. The combustion engine may alternatively be a petrol, gas or ethanol engine.

The engine 230 has an output shaft 231 connected to a clutch 235. The clutch may for example be of a conventional disc type, such as a two-disc clutch. The clutch 235 is also connected to a shaft 236. The shaft 236 is an input shaft to a gearbox 240. The gearbox 240 has an output shaft 243 adapted to transmitting power from the engine to a number of vehicle wheels

245 in a conventional manner. The clutch 235 is adapted to being able to interrupt the power transmission in the driveline which comprises the shaft

231 , the clutch 235, the shaft 236, the gearbox 240 and the shaft 243.

According to a version, the control unit 200 is adapted to controlling both the clutch 235 and the gearbox 240. The control unit 200 is adapted to communication with the clutch 235 via a link 237. The control unit 200 is adapted to communication with the gearbox 240 via a link 239. According to a version, an existing tachograph 280 is provided in a driving cab of the tractor unit 110. The tachograph 280 is adapted to signal communication with the control unit 200 via a link 285. The tachograph 280 is adapted to accommodating and holding a tachograph card 281. The tachograph 280 is described in more detail with reference to Figure 3.

The tachograph 280 is also adapted to communication with a second control unit 210 via a link 286. The second control unit 210 is adapted to communication with the control unit 200 via a link 215. The second control unit 210 may be detachably connected to the control unit 200. The second control unit 210 may be a control unit external to the vehicle 100. The second control unit 210 may be adapted to performing the innovative method steps according to the invention. The second control unit 210 may be used for transferring software to the control unit 200, particularly software for implementing the innovative method. The second control unit 210 may alternatively be adapted to communication with the control unit 200 via an internal network in the vehicle. The second control unit 210 may be adapted to performing substantially similar functions to the first control unit, e.g. controlling the engine 230, the clutch 235 and the gearbox 240 on the basis of information received from the tachograph 280.

According to this version, the control unit 200 is also adapted to controlling the engine 230 via a link 233.

The control unit 200 is signal-connected via a link 251 , or connected in some other way, to operating means 250, e.g. injection valves for injection of fuel to the engine's cylinders. Other operating means may be actuators for VGT (variable geometry turbocharger), intake throttle and exhaust brake, and valves for urea injection to an SCR catalyst. Separate control units may of course be provided for the engine and the gearbox respectively, but in that case they need to be connected together to enable them to communicate relevant information between them.

According to this version, the control unit 200 is adapted to controlling the gearbox 240 via a link 239. To this end, the control unit 200 is signal- connected to operating means (not depicted) for changing of gear steps in the gearbox in response to command signals initiated by the operating means 250.

Sensors 260 are adapted to communication with the control unit 200 via a link 261. The sensors 260 may for example be sensors to measure temperature, speed, pressure, concentration and moisture content.

Figure 3 illustrates schematically a subsystem 300 of the vehicle 100. A number of the components of the subsystem 300 are also described with reference to Figure 2. Also illustrated is a speed sensor 270 adapted to communication with the tachograph 280 via a link 271. The speed sensor 270 is adapted to sending information at certain intervals of time about the vehicle's speed to the tachograph for storage therein.

For the sake of clarity it should be noted that tachograph 280 means the device which has by law in a number of countries to be installed in, for example, heavy trucks and buses involved in commercial traffic. The tachograph 280 is adapted to continuously recording, inter alia, vehicle speed and driving and rest times. The tachograph 280 is adapted to storing operating parameters generated during the operation of the vehicle. These operating parameters may comprise, for example, engine speed, vehicle speed etc.

The tachograph 280 is equipped with a communication device, e.g. a touch screen or keypad. The tachograph 280 is a digital tachograph. A driver of the vehicle can put information in manually about the geographical area in which the vehicle is situated, i.e. the vehicle's location, as regards geographical area. This information thus comprises information about the vehicle's location. Legal requirements in several different countries call for input of information about the vehicle's location according to certain criteria, e.g. at the beginning of a driving shift and/or when the driver drives the vehicle across a national frontier or some other area boundary. Information about the vehicle's location is also referred to as a first information INFO1.

The tachograph 280 is also equipped with a device for generating information about current time and date. Information about current time is also referred to as a second information INFO2. Current time may for example mean a time corresponding to the time of input of the first information or a time when a driver's driving shift begins. Information about current date is also referred to as a third information INFO3. Current date may for example mean a date when input of the first information INFO1 takes place or a date when a driver's driving shift begins.

The tachograph card 281 may be associated with a certain driver and contain information about him/her. The tachograph 280 is adapted to reading information from a chip c on the tachograph card 281. The tachograph 280 is also adapted to writing information to a chip c on the tachograph card 281.

For example, information about the vehicle's speed and the driver's driving time may be transcribed to a memory in the chip c. Information about the driver is referred to as a fourth information INFO4. The fourth information

INFO4 may comprise information about the driver's name, driving style and/or vehicle-specific settings.

According to a version, the tachograph 280 is adapted to sending to the control unit 200 a signal S1234 comprising the first, second, third and fourth information. Alternatively, the tachograph 280 is adapted to sending to the control unit 200 a signal comprising the first, second, third and fourth information in separate signals S1 , S2, S3 and S4 respectively. The tachograph may also be adapted to sending to the control unit 200 a signal comprising one or more of the first, second, third and fourth signals, e.g. a signal S123 which comprises the first, second and third information.

According to a version, the tachograph 280 is adapted to sending the first information INFO1 to the control unit 200 substantially immediately after a driver has put the information INFO1 into the tachograph 280. This has the effect that the control unit 200 can quickly start controlling, for example, the vehicle's engine and transmission in order to improve the drivability of the vehicle according to the invention.

The control unit 200 is adapted to receiving signals from the tachograph 280. The sending of information from the tachograph 280 to the control unit 200 may be initiated either by the tachograph itself or by a command signal delivered by the control unit 200.

The control unit 200 has a number of different state models stored in a memory. One such model is a climate model. There may be a plurality of different climate models. A climate model may be associated with a certain geographical area indicated by the first information INFO1. A climate model may be used for generating output data usable for influencing the operating means 250 in order to improve the vehicle's drivability, emissions or economics.

When the control unit receives the first information, it can select a climate model associated therewith and control the vehicle on the basis of output data from the climate model. A climate model may be applicable within the borders of a certain country. Another climate model may be applicable within a geographical area defined by parts of a country, more than one country or parts of different countries. The choice of a climate model on the basis of the first information may be made by a matching procedure, e.g. by means of a table.

According to an aspect of the invention it is advantageous to use the first information INFO1 for choice of climate model, since the driver may be held personally responsible for the first information being correct from a legal perspective.

According to an aspect of the invention, the first information INFO1 may be used for choosing a set of parameters usable as input for a climate model.

According to a version, the second INFO2 and/or third INFO3 information may also be used for choice of climate model.

According to a version, the first, second and third information is used for choice of state model to make it possible to improve the drivability of the vehicle according to an aspect of the invention. According to a preferred version, the first, second and third information is used for choice of climate model to make it possible to improve the drivability of the vehicle according to an aspect of the invention. A state model may generate a state, e.g. a moisture content of the air surrounding the vehicle. These states may be used by handling units (see below) in the control unit for controlling the vehicle in order to improve the drivability according to the invention.

According to an embodiment, the first, second and third information may be controlled by a comparison procedure using information from other sources than the tachograph, e.g. a GPS or an internal clock of the control unit. If the first, second or third information does not seem reasonable, an error message may be communicated to the control unit 200 and be displayed there on a screen. A number of sensors 260 are adapted to communication with the control unit 200. These sensors provide other information usable for driving the vehicle in a desired manner.

A number of so-called virtual sensors are stored in the control unit 200 in the form of software. Virtual sensors can calculate parameters which are expensive, difficult or impossible to measure with physical sensors. These parameters are usable as input in various state models or for handling units to make it possible to control operating means so that the drivability of the vehicle can be improved. The first, second and third information may be used as input to a virtual sensor. A virtual sensor may provide output data based on information which is legally binding for the driver about legal requirements within the area in which the vehicle is situated. In a similar way, a virtual sensor may provide output data based on information which is legally binding for the driver about the vehicle's location so that a correct driving mode or climate model can be adopted in order, for example, to minimise emissions from the vehicle.

A number of so-called handling units (also known as "managers") are stored in the control unit 200 in the form of software. Each of them is adapted to driving mode selection for the vehicle. One driving mode may relate to setting the vehicle in motion. Another driving mode may relate to warming up the vehicle's engine. A further driving mode may relate to driving the vehicle in a certain climate (which has a certain average temperature and air humidity). A handling unit may choose driving mode on the basis of one, or a combination or two or more, from among the first, second, third and fourth information.

Providing one or more from among the first, second, third and fourth information makes it possible for a driving mode to be selected for the vehicle so that the control unit can deliver correct reference values for regulators so that the latter may provide optimum actual values for operating means. Figure 4 illustrates schematically a flowchart of a method for improving the drivability of a motor vehicle, according to an embodiment of the invention.

The method comprises a first method step s401 comprising the steps of

- transmitting information about current time, date and the vehicle's location from a tachograph to a control unit, and of

- controlling the vehicle on the basis of the transmitted information so that improved drivability of the vehicle is achieved. The method ends after step s401.

Step s401 may alternatively comprise the steps of

- transmitting information about the vehicle's location, as regards geographical area, from a tachograph to a control unit, and of - controlling the vehicle on the basis of the transmitted information so that improved drivability of the vehicle is achieved.

According to an example, a driver has put said information about the vehicle's location manually into the tachograph 280.

Figure 5 depicts a diagram of a version of a device 500. The tachograph 280 and the device 210 may be of similar construction. It should be noted that the tachograph 280 is also equipped to accommodate a tachograph card which has a chip, or some other data storage medium. The tachograph 280 can read/write information from/to its chip. The control units 200 and 210 described with reference to Figure 2 may in a version comprise the device 500. The device 500 comprises a non-volatile memory 520, a data processing unit 510 and a read/write memory 550. The non-volatile memory 520 has a first memory element 530 in which a computer programme, e.g. an operating system, is stored for controlling the function of the device 200. The device 500 further comprises a bus controller, a serial communication port, I/O means, an A/D converter, a time and date input and transmission unit, an event counter and an interruption controller (not depicted). The non-volatile memory 520 has also a second memory element 540.

A computer programme P comprising routines for improving the drivability of a motor vehicle is provided. The programme P comprises routines for controlling, for example, the vehicle's engine, transmission, including clutch and gearbox, in accordance with the innovative method. Controlling the vehicle on the basis of information from the tachograph may involve data processing of virtual sensors, state models, handling units and regulators which may be stored in a memory in the control unit, e.g. the memory 550 or

560. The programme P may be stored in an executable form or compressed form in a memory of 560 and/or in a read/write memory 550.

Where it is stated that the data processing unit 510 performs a certain function, it means that the data processing unit 510 effects a certain part of the programme which is stored in the memory 560 or a certain part of the programme which is stored in the read/write memory 550.

The data processing device 510 can communicate with a data port 599 via a data bus 515. The non-volatile memory 520 is intended for communication with the data processing unit 510 via a data bus 512. The separate memory

560 is intended to communicate with the data processing unit 510 via a data bus 511. The read/write memory 550 is intended to communicate with the data processing unit 510 via a data bus 514. For example, the links 215, 233, 237, 239, 285, 288 and 291 may be connected to the data port 599 (see

Figure 2).

When data are received on the data port 599, they are stored temporarily in the second memory element 540. When input data received have been temporarily stored, the data processing unit 510 will be ready to effect code execution in a manner described above. According to a version, information signals, e.g. the signal S1234, received on the data port 599 contain information provided by the tachograph 280 (see Figure 2). The information may comprise the first, second, third and fourth information (see Figure 3). This information may be used by the device 500 for controlling, for example, the vehicle's engine and transmission in accordance with stored routines which cater for prevailing legal requirements and/or climate.

Parts of the methods herein described may be effected by the device 500 by means of the data processing unit 510 which runs the programme stored in the memory 560 or the read/write memory 550. When the device 500 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 or to limit the invention to the variants described. Many modifications and variants will obviously be apparent to one skilled in the art. The embodiments have been chosen and described in order best to make clear the principles of the invention and its practical applications and hence to make it possible for one skilled in the art to understand the invention for various embodiments and with the various modifications appropriate to the intended use.