WO2020002166A1

WO2020002166A1 - Method for generating an actuation signal for a vehicle, and device for same

Info

Publication number: WO2020002166A1
Application number: PCT/EP2019/066549
Authority: WO
Inventors: Urs Natzschka
Original assignee: Robert Bosch Gmbh
Priority date: 2018-06-25
Filing date: 2019-06-21
Publication date: 2020-01-02
Also published as: DE102018210295A1

Abstract

The invention relates to a method for generating an actuation signal (15) for a vehicle (1). Roadway information, comprising a roadway inclination (12) and a friction coefficient (13), is obtained for a route section to be traversed by the vehicle (1). The invention is characterized in that vehicle parameters (14) are obtained, the degree of risk of the vehicle (1) skidding, in particular skidding downhill, in or opposite the driving direction on the route section is determined from the obtained roadway information (12, 13) and the vehicle parameters (14), and if a risk threshold is exceeded, the actuation signal (15) is generated. The invention also relates to a device for carrying out the method and to a computer program.

Description

Method for generating a control signal for a vehicle and device therefor

State of the art

DE 101 26 459 CI discloses a system and a method for determining road friction values in the area of a vehicle. The system has a device for determining a current geographical position of the vehicle and at least one transmitting device for transmitting at least road surface friction data, in a further development also gradient data, in the area of the current geographical position of the vehicle to a receiving unit arranged internally or externally of the vehicle on. Also disclosed is the creation of a coefficient of friction map and a map with information about slope information based on the transmitted information. A combination with a navigation system is also disclosed, the current route condition being incorporated into an automatic route guidance of the vehicle, so that a selection of roads that can be driven safely can be made and at the same time the driving dynamics of the vehicles traveling on these roads are adjusted.

Advantages of the invention

The invention relates to a method and a device for controlling a vehicle, it being determined as a function of a coefficient of friction for a roadway in a section of the route to be traveled by the vehicle, an incline of the section of the route and relevant data of the vehicle whether there is liability between the vehicle and the roadway in the route section allows the route section to be driven safely without slipping in the longitudinal direction. For this purpose, a method for generating a control signal for a vehicle is proposed,

where, for a section of the route to be traveled by the vehicle, route information, including road gradient and coefficient of friction, is obtained,

which is characterized by

that vehicle parameters are obtained

that the level of a risk of slipping, in particular slipping, of the vehicle in or against the direction of travel on the route section is determined from the roadway information obtained and the vehicle parameters, and that the control signal is generated if a risk limit value is exceeded.

Furthermore, an apparatus for performing the method is proposed.

The section of the road to be traveled by the vehicle can in particular be understood to mean a section of a road which, based on a current vehicle position when the vehicle is moving forward, will be reached in the future and lies on a route of the vehicle. The vehicle position can advantageously be determined with a location component connected to the vehicle, such as a receiver for satellite signals from a satellite location system such as GPS, GLONASS or GALILEO. The vehicle position relative to the route section to be traveled can be determined in particular by comparing the vehicle position determined with the location component with a digital map, in which map a traffic route, in particular road network, including the route section to be traveled is depicted. The route section to be traveled then results as part of a route that is still in front of the vehicle, for example, from a vehicle navigation system starting from a current location to a specific destination or, for example, from an electronic horizon component based on possible and likely from the vehicle in the future route sections still to be driven is determined. The coefficient of friction of one and in particular the route section in question is understood to mean a coefficient of friction or coefficient of friction. With knowledge of the relevant parameters of a further friction partner involved, in the present case the vehicle parameters, the coefficient of friction enables the fleas of the frictional forces between the road surface and the vehicle contact points with the road surface to be determined, in the case of a motor vehicle, for example a truck, ie its tires with the road surface.

It is provided here that a friction between the vehicle or vehicle preparation and the section of the route is determined on the basis of the relevant vehicle parameters, in particular the vehicle weight, axle load distribution or absolute axle load and tires, and information about the gradient of the section of the route and its nature. The nature of the track of the route section includes conditions due to weather or pollution, such as a film of water, a frost, ice or snow or the like, or a layer of dust, an oil film or chemicals on the road or the like.

The information about the road gradient of the route section in question, if it is not already present in the digital map, can be recorded by vehicles traveling on the route section and reported via preferably wireless interfaces and then assigned to the route section on the map. In a similar way, information about the road surface condition of the route section of vehicles in traffic can also be recorded using on-board sensors and reported via preferably wireless interfaces.

On the one hand, the messages can be reported to other vehicles in the form of a so-called vehicle-to-vehicle, with particular preference being given to addressing other vehicles in the vicinity of a reporting vehicle. The messages can, however, also be transmitted to a central facility, here and hereinafter also referred to as the center, where these are consolidated and aggregated so that they can subsequently be transmitted wirelessly to affected traffic participants, including, for example, the vehicle that has to travel the section of the route. These aggregated messages can be transmitted to the vehicle concerned, for example via radio or mobile radio.

The fleas of a risk of slipping, in particular slipping, of the vehicle in or against the direction of travel on the route section in question to be driven can be determined from the information obtained from the roadway information and the vehicle parameters. If one assumes that, in addition to the coefficient of friction of the road surface, the current vehicle weight and the number of wheels are first and foremost determinative for determining a safe flow friction for a controlled ferry operation, the quality of the forecast can be increased by: empirical values are entered in advance on test tracks or field data are evaluated over time and these data are either stored in the vehicle for further calculations or made available via a cloud service. According to the invention, when the risk limit value is exceeded, the control signal is generated by the risk.

Slipping here means a brief standstill of the wheels of a braked axle or a brief slip of the wheels of a drive axle, so that the vehicle comes to a standstill when braking or starts or accelerates only when the accelerator pedal is pressed.

Slipping means an uncontrolled gliding of the vehicle, which cannot be controlled by drive or brake interventions, so that in the worst case the vehicle only comes to a standstill, for example when slipping onto a surface with a better grip. An initial slipping as a result of accelerator pedal actuation can often also result in slipping. A control signal is understood here to mean a signal which controls a component, which then carries out an action or which triggers a function.

The component can be, for example, a driver information system in the vehicle which, in response to the control signal, outputs a warning signal to the vehicle driver, which is preferably relevant to the upcoming critical situation.

The component can, for example, also be a driver assistance system, the control signal triggering, for example, locking of a transmission differential of the motor vehicle and thus preventing a wheel of a driven vehicle axle from rotating unilaterally, or which otherwise affects an adjustment of an existing anti-slip control or an anti-lock braking system. The control signal can for example also act on the vehicle drive, for example to influence or adapt the sensitivity of an anti-slip control. The control signal can also act to influence the mode of operation of a vehicle brake system, for example in order to bring the vehicle to a standstill reliably and in a controlled manner in the event of impending slipping by targeted braking interventions, if necessary also only on individual wheels of the vehicle or on different wheels of the vehicle with different parameters , And in a controlled manner it can be understood that the vehicle preferably does not position itself transversely to the direction of the course of the lane, but instead comes to a standstill in the longitudinal direction and thus blocks adjacent driving

The component can also be a vehicle navigation system, for example, which is triggered by the control signal, recalculates a driving route based on the current location, with notification and detour of the section of the route that is actually to be traveled, but which is rated as critical for the driving stability of the vehicle. Further components or functions that can be controlled by the control signal or further uses of the control signal are conceivable and are within the scope of the present invention.

The information about the coefficient of friction on the section of the route to be traveled can advantageously be received via a communication interface of a device installed and / or operated on the vehicle for generating the control signal.

The information about the coefficient of friction on the route section to be traveled can be received by one or more other vehicles which are located in the area of the route section to be traveled. As an alternative or in addition, the information about the coefficient of friction on the section of the route to be traveled can also be received by a control center external to the vehicle.

This has the advantage that information about the coefficient of friction of the road on the section of the route to be traveled is obtained with a high degree of topicality. This ensures that the risk calculation is highly reliable. To recognize the topicality of the coefficient of friction information, it can also be assigned time stamps or expiry dates, which can be taken into account in the receiving device for carrying out the method when determining the risk, in particular if information about the coefficient of friction or the coefficient of friction is also influencing Values, such as weather information, are more up-to-date from other sources.

In an advantageous embodiment, the vehicle parameters are obtained from a memory in the vehicle. The vehicle parameters can advantageously be recorded using vehicle-specific vehicle sensors and written to the memory. As a modification, the vehicle parameters can also be recorded continuously or immediately before the time of the risk calculation using vehicle-specific vehicle sensors. The vehicle parameters include the vehicle parameters relevant for the risk calculation. These include in particular a vehicle weight and / or an axle load distribution and / or an absolute axle load, in particular of one or more driven and / or braked vehicle axles, and / or information about the tires of the vehicle.

drawings

Embodiments of the invention are shown in the drawings and who explained the in more detail below.

Show it

FIG. 1 shows a block diagram of a system for carrying out the method according to the invention, comprising the device according to the invention, which is designed to carry out the method according to the invention,

Figure 2 is a flowchart of an embodiment of the inventive method.

Description of the embodiments

1 shows a vehicle 1, a second vehicle 2, a third vehicle 3 and a control center 4.

The vehicle 1 is a motor vehicle, for example a truck. The vehicle has a device 10, which is set up to generate a control signal 15 on the basis of input variables or information received about a section of the route to be traveled by the vehicle if a result of a summary of the information obtained results, that the vehicle 1 slips, in particular slips, on the route section to be traveled in the longitudinal direction, ie along or against the direction of travel.

Such slipping or slipping in the longitudinal direction often results in practice from a combination of high vehicle weight, a rising or falling road surface and insufficient friction between the road surface and the vehicle, here in particular the contact points of the vehicle with the road surface, in the case of a motor vehicle as a rule its tires. In practice, this can be observed in particular on trucks on inclines or downhill gradients in winter and both with regard to the effects on the flow of traffic, for example as a result of trucks standing overturned or tipping over, as well as the risk potential for the driver as well as the drivers nearby evaluate vehicles in a particularly critical manner.

The device 10 accesses information about route sections to be traveled via suitable communication interfaces. A section of the route to be traveled is in particular a section of the route which the vehicle will be able to travel in the future as part of its current journey. This can, for example, be part of a route calculated using a navigation system or part of a probable route that has been determined using an electronic horizon system.

To determine a current position 11, the device accesses a locating module 110. This can preferably be a satellite location module for receiving and evaluating GPS, GLONASS and / or GALILEO satellite signals and provides position data 11 of the current vehicle position at its output.

The device also accesses a map memory 120, in which a digital map including information about road gradients 12 of route sections depicted or represented in the map is contained. The Map memory 120 can be part of the vehicle or of a system operated in the vehicle, for example a navigation system. Alternatively, the card memory 120 can also be arranged externally with respect to the vehicle 1, for example at an online service provider, and can be connected to the device 10 via a radio communication interface or can be connected if required.

Device 10 also accesses information relating to the condition of road sections, in particular coefficients of friction 13 here. In a preferred embodiment, this information about friction coefficients 13 can be received via a wireless communication interface 130.

On the one hand, other vehicles in traffic, here a second vehicle 2 and a third vehicle 3, which are located on a section of the route with conspicuous, that is to say deviating from the normal road surface condition, can detect this road surface condition by means of their vehicle-side sensors 25 and 35, respectively or derive from the sensor data. The derived information about the road surface condition, in the present case in particular information relating to the friction coefficients of the affected route sections, is identified with identifiers for the affected route sections and as road condition reports 22 by the second vehicle via its second communication interface 21 and 32 by the third vehicle 3 via its third communication interface 31 , for example via mobile radio.

On the basis of the identification of the affected route sections, the friction values of the affected route sections, which are in the road condition reports 22 and 32 in the receiving units, lying in front of the device 10 of the vehicle 1 as well as in a control center 4, can be found in the digital map in the map memory 120 of the vehicle 1 and are mapped in a second card in a second card memory 420 of the control center.

The control center 4 is designed to create a coefficient of friction map or database 430 in which the coefficient of friction preferably also includes a time stamp indicating the receipt of the relevant road condition message 32 and / or assign a validity period or an expiry date. The control center 4 is also designed to send the information about sections of the route with conspicuous friction values as traffic reports 42 via a fourth communication interface 41, for example as part of digitally coded traffic reports via radio or alternatively or additionally via mobile radio or other transmission channels.

The vehicle 1 also has a memory 140 in which the vehicle parameters 14 are stored. In connection with the present invention, these vehicle parameters include those parameters which, in conjunction with the slope information for a section of the vehicle to be driven by, and the coefficient of friction information available for this section of the route enable a statement to be made as to whether slipping or it is even likely that the vehicle will slip on this section of the route to be traveled. In a preferred embodiment, these vehicle parameters include the vehicle weight, the axle loads of the individual vehicle axles, in particular the axle loads of driven and / or braked vehicle axles, axle load distribution or information about the tires of the vehicle 1, somewhat the tread depth, air pressure, rubber compound or age of the tires. Not all of this information must be available, and further information is also possible.

Parts of these vehicle parameters 14 stored in the memory 140 are recorded continuously or at regular intervals automatically by means of in-vehicle sensors 150. This applies in particular to vehicle weight taking into account an unladen weight, axle load and axle load distribution. Tire air pressure. Other information such as tread depth or age of the tires can be written into the memory 140 manually, for example, by the vehicle driver or another person, preferably at regular intervals.

From the information about the route sections to be traveled, including road gradients 12, coefficients of friction 13 of the road surface of the route sections and the relevant vehicle parameters, the device determines the level of a risk of slipping, in particular sliding of the vehicle 1 on these route sections. In the event that the determined risk for one of the considered route sections exceeds a risk limit value, the device 10 generates the control signal 15 for controlling a component 100 of the vehicle or for triggering a function of the vehicle, for example for issuing a warning message to the driver, which preferably also the type in addition to the affected route section indicates the hazard or the extent of the risk. Alternatively or in addition, a function can also be triggered automatically, which the vehicle driver would typically trigger manually in response to such a warning message. For example, a route recalculation can be triggered in a vehicle navigation system, whereby the section of the route that is critically assessed is avoided.

The sequence of the method is briefly outlined in FIG.

In step 200, a route from a current location to a destination is determined using a vehicle navigation system.

In step 210, preferably while the vehicle 1 is traveling, the current position of the vehicle 1 is determined on the basis of the position information 11 obtained from the locating unit 110 and compared with the map data from the digital map contained in the memory 120.

In step 220, information about route sections still to be traveled is retrieved from the memory 120 on the basis of the determined position of the vehicle 1 and the known driving route of the vehicle 1. This information includes slope data 12 in particular.

In step 230, information about friction values 13 is obtained via the communication interface 130. These can be distributed using the radio method and received by vehicle 1. In this case, these are compared with the information about route sections still to be traveled, which were loaded in step 220. However, these can also be specifically requested from the control center 4 for the route sections still to be traveled, for example via mobile radio. In step 240, the vehicle parameters 14 relevant for determining a slip or slip risk for the vehicle are retrieved from the memory 140.

In step 250, the risk of the vehicle 1 slipping or slipping on these sections of the route to be traveled is determined by looking at the incline information relating to the route sections still to be traveled ahead, the friction coefficients associated with the section and the vehicle parameters. In the event that this risk exceeds a risk limit on one of the sections of the route still to be traveled

In step 260, the control signal 15 is output, with which a component 100 of the vehicle 1 is triggered or a vehicle function, for example the output of the warning message, is triggered.

As already stated, a route recalculation can also be triggered. It goes without saying that in this case steps 200 to 260 are carried out on the basis of the newly calculated route and the sections of the route covered by it.

The method does not end, but runs repeatedly, preferably as long as the vehicle 1 is in motion.

The method can preferably be implemented in the form of a computer program which is executed on a computing unit or a processor which is part of the device 10.

Claims

claims:

1. Method for generating a control signal (15) for a vehicle (1), with lane information, including lane gradient (12) and coefficient of friction (13), being obtained for a section of the route to be traveled by the vehicle (1),

characterized,

that vehicle parameters (14) are obtained,

that from the roadway information (12, 13) and the vehicle parameters (14) received, the amount of a risk of slipping, in particular slipping, of the vehicle (1) in or against the direction of travel on the route section is determined

and that the control signal (15) is generated when a risk limit value is exceeded.

2. The method according to claim 1,

characterized in that the information about the coefficient of friction (13) on the route section to be traveled is received via a communication interface (130).

3. The method according to claim 2,

characterized in that the information about the coefficient of friction (13) on the route section to be traveled is received by one or more further vehicles (2, 3) located in the area of the route section to be traveled, and / or that the information about the Friction coefficient (13) on the route section to be traveled by a vehicle (1) external control center (4) received.

4. The method according to any one of the preceding claims,

characterized in that the vehicle parameters (14) are obtained from a memory (140) in the vehicle (1).

5. The method according to any one of the preceding claims, characterized in that the vehicle parameters (14) with vehicle's own vehicle sensors (150) are recorded or recorded and written into the memory (140).

6. The method according to any one of the preceding claims, characterized in that the vehicle parameters (14) include a vehicle weight and / or an axle load distribution and / or information about the tires of the vehicle (1).

7. The device, set up to generate a control signal (15) in a vehicle (1), set up to carry out the method according to one of the preceding claims.

8. Computer program with program code which is set up to execute the method according to one of claims 1 to 7 when it is executed on a computing unit or a processor.

9. A data carrier comprising a computer program according to claim 8.