METHOD AND DEVICE FOR ASSISTED, SEMI-AUTOMATED, HIGHLY AUTOMATED, FULLY AUTOMATED OR DRIVERLESS DRIVING OF A MOTOR VEHICLE

Description

[0001] The invention relates to a method and a device for automated or driverless driving of a motor vehicle. The method is based on the classifications of the German Automotive Industry Association (VDA) for automated driving (Level 1 - assisted, Level 2 - partially automated, Level 3 - highly automated, Level 4 - fully automated, and Level 5 - driverless). All of the above-mentioned levels of automation are collectively referred to below as "automated driving."

[0002] Motor vehicles with automated driving are already known. These vehicles can be passenger cars (PCs), trucks (HGVs), or buses.

[0003] What most of the proposed embodiments have in common is that they have at least one control unit responsible for navigation and trajectory planning. This can be a central control unit, or the functionality can be distributed across multiple control units. Furthermore, such motor vehicles have subsystems that implement the control unit's driving dynamics requirements or provide environmental data. For example, one subsystem is a service brake system, one subsystem is a parking brake system, one subsystem is a steering system, one subsystem is a drive system, and one subsystem is an environmental sensor system for detecting lanes, obstacles, and other motor vehicles. The control unit then generates control signals for the subsystems depending on the planned trajectory, which are then implemented by the subsystems. These subsystems are designed in such a way that a single error cannot lead to total failure of the subsystem.This can be achieved through redundancies or fallback systems. The latter often provide less than full performance in the event of a failure, but sufficient performance to bring the vehicle to a stop in a safe location.

[0004] Such a device for automated driving is known from WO 2010 / 048611 A1, wherein the subsystems are designed redundantly and an emergency stop is carried out in the event of a fault.

[0005] DE 10 2014 213 171 A1 discloses a system for autonomous vehicle guidance, comprising a plurality of electrical and / or electronic components, wherein the components are designed to cooperate to carry out autonomous vehicle guidance. Each of the components is assigned to a first set of components or a second set of components, wherein the components of the first set are designed to carry out at least limited and / or time-limited autonomous vehicle guidance even if the components of the second set fail. Furthermore, the components of the second set are designed to carry out at least limited and / or time-limited autonomous vehicle guidance even if the components of the first set fail. It is further disclosed that this emergency operation is transmitted to other participants via Car2x communication so that they can adapt to it.

[0006] EP 2 921 362 A1 discloses a method for automated, semi-automated, highly automated, fully automated, or driverless driving of a motor vehicle, using at least one control unit for navigation and trajectory planning and several subsystems, wherein the subsystems implement the control unit's driving dynamics requirements or provide environmental data. A monitoring function is assigned to the environmental data subsystem, which monitors the sensor failure probability. The monitoring function transmits the currently possible performance, or more precisely, the failure probability or the time of failure, to the control unit.The control unit is designed to adapt the navigation and trajectory planning depending on the transmitted performance in such a way that the journey can be continued despite reduced performance, for example by selecting an alternative route for which the probability of failure no longer exists.

[0007] DE 10 2013 021 872 A1 discloses a motor vehicle comprising a plurality of wheels and a braking system with hydraulically actuated brakes assigned to each wheel, at least one brake circuit via which the brakes can be actuated, a brake booster via which the brake circuit can be operated, the brake booster being actuated via a brake pedal actuated by the driver, and at least one pressure generating and / or pressure accumulating device controllable via a control device, via which the hydraulic pressure of the brake circuit can be modulated. Furthermore, at least one electric motor is provided, via which, in the event of a detected malfunction within the braking system, a deceleration torque for braking the vehicle to a standstill can be generated by automatically switching to a generator mode.

[0008] The invention is based on the technical problem of improving a method for automated driving of a motor vehicle in such a way that the availability of the function is improved. A further problem is the creation of a device for automated driving that also improves the availability of the function.

[0009] The solution to the technical problem results from a method having the features of claim 1 and a device having the features of claim 6. Further advantageous embodiments of the invention result from the subclaims.

[0010] The method for automated driving of a motor vehicle is carried out by means of at least one control unit for navigation and trajectory planning of an automated journey of the motor vehicle and several subsystems, whereby the subsystems implement driving dynamics requirements of the control unit.

[0011] At least one subsystem is assigned a monitoring function, which is used to determine the functionality of the subsystem. The monitoring function can be part of the subsystem or an external observer. For example, the braking system is activated in certain situations and the brake pressure is measured (e.g. when stationary at a red light). The monitoring function transmits the currently possible performance level to the control unit. The currently possible performance level can be transmitted qualitatively or quantitatively. Qualitatively, the message consists only of the information that performance is limited, whereas quantitatively, a specific number or range of numbers is specified, for example, the maximum possible braking deceleration currently.The specification of the currently possible maximum performance capability can also include a period within which the performance capability is still present. The control unit then adapts the navigation and trajectory planning depending on the transmitted performance capability such that the automated journey can be continued despite reduced performance. Trajectory planning represents the short-term future trajectory of the vehicle within the possible lanes, whereas navigation planning represents the longer-term route (driving the motorway from A to B). The adaptation can occur in both planning phases, but may be limited to one planning phase depending on the transmitted performance capability. All subsystems can be provided with a monitoring function and transmit their performance capability to the control unit.It may be provided that individual subsystems communicate the performance quantitatively, while others only qualitatively. The subsystems are a service brake system, a parking brake system, a steering system, a drive system, and a transmission system.

[0012] Furthermore, if a subsystem's performance is reduced, the control unit prepares at least one other system or subsystem so that it at least partially supports the subsystem with the reduced performance. For example, a retarder or an exhaust brake is prepared for use by, for example, changing the gear and / or speed to areas of greater efficiency for these systems. Such braking systems are used particularly in modern trucks. Another alternative system is a hybrid drive system, which is set to increased recuperative braking when performance is reduced. If the steering system's performance is reduced, steering interventions can also be implemented through asymmetrical braking interventions; for this, the speed may need to be adjusted beforehand so that the service brake is available for this purpose.

[0013] Furthermore, if the performance of at least one subsystem is reduced, road sections with predetermined characteristics are no longer considered in navigation planning. For example, if the performance of the service braking system is reduced, roads with a gradient greater than a threshold value are no longer driven on. If such roads were included in the navigation planning, the control unit calculates an alternative route excluding such roads. If the performance of the steering system is reduced, winding roads, for example, can be excluded. The basic idea is to use specific road sections in navigation planning that can be safely driven with the reduced performance, so that the automated journey can continue despite the reduced performance.

[0014] In one embodiment, at least one additional subsystem for providing environmental data is present, to which a monitoring function is assigned that transmits the current performance to the control unit. The additional subsystem is, for example, a sensor system for detecting lanes, obstacles, and other vehicles.

[0015] In one embodiment, the control unit additionally calculates stabilization functions (such as ESP interventions). If the performance of at least one subsystem is reduced, the navigation and trajectory planning are adjusted such that stabilization functions do not need to be performed. This can be achieved, for example, by a deliberately defensive driving style.

[0016] In another embodiment, the speed of the motor vehicle and / or the required safety distance from a vehicle traveling ahead are increased. Both measures ensure that the journey can be continued despite a reduced performance of the service brake system. Both measures represent changes to trajectory planning.

[0017] In a further embodiment, other vehicles in the vicinity of the vehicle are informed of the reduced performance and / or an adjusted driving style via a Car2Car interface. This allows the surrounding vehicles to adapt to the adjusted driving style and, for example, make adjustments regarding speed and safety distance or generally adjust trajectory planning.

[0018] In a further embodiment, the navigation planning determines a suitable stopping point for the motor vehicle depending on the reduced performance, for example a workshop that is still accessible, a suitable parking space or the next emergency stopping bay.

[0019] The invention is explained in more detail below using a preferred embodiment. The single figure shows a schematic block diagram of a device for automated driving of a motor vehicle.

[0020] In Fig. 11 shows a device 1 for the automated driving of a motor vehicle. The device 1 comprises a control unit 2, various subsystems 3-7, a car-to-car interface 8, and further systems 9-11. The control unit 2 is responsible for navigation and trajectory planning as well as stabilization functions of the automated driving. The control unit 2 can be a single central control unit or divided into several control units. The control unit 2 is bidirectionally connected to the subsystems 3-7. The subsystems 3-7 represent the sensors (e.g., camera, radar, ultrasound, lidar, etc.) and actuators of the device 1. For example, subsystem 3 is at least one sensor unit for detecting the surroundings of the motor vehicle, subsystem 4 is a service brake system, subsystem 4a is the parking brake system, subsystem 5 is a steering system, subsystem 6 is a drive system, and subsystem 7 is a transmission system.Subsystems 3-7 implement target specifications specified by control unit 2 based on navigation and trajectory planning as well as the stabilization functions. In advance, subsystems 3-7 transmit their performance capability to control unit 2. For this purpose, subsystems 3-7 have monitoring functions by means of which the available performance capability can be determined qualitatively or quantitatively. This information can, for example, consist of the maximum target specification that subsystem 3-7 can actually implement. In the service brake system, this can, for example, be a value for maximum deceleration. However, the information can also consist of the fact that a subfunction is not available (e.g. 4th gear is currently unavailable) or that a certain target specification is only available for a limited time and / or for a limited number of actions.Thus, control unit 2 can adapt the target specifications for subsystems 3-7 to the available performance of subsystems 3-7. Via the Car2Car interface 8, control unit 2 can inform other motor vehicles in the vicinity of its adjusted driving style. Furthermore, information from other vehicles can also be received via the Car2Car interface 8 (for example, that they have also adjusted their driving behavior due to reduced performance) and taken into account in navigation and trajectory planning in control unit 2. Control unit 2 is connected to the Car2Car interface 8 via a bus system 12, via which control unit 2 can receive further information from other control units and sensors. The other systems 9-11 are, for example, a retarder, an exhaust brake, and an electric motor or a hybrid control unit.Finally, the control unit 2 also outputs control signals S in advance for other systems such as direction indicators.

[0021] The operation of device 1 will be briefly explained using a scenario. It is assumed that the service braking system has reported reduced performance to control unit 2, whereas all other subsystems are operating at full capacity. Control unit 2 reacts to the reduced performance by reducing the speed as a target value to subsystem 6. In addition, control unit 2 adjusts the safety distance to a preceding vehicle during its trajectory planning. The transmission system is adjusted using an adjusted target value such that at least one of systems 9-11 can be operated at a high-efficiency operating point, if necessary, to provide additional braking power.This means that, despite reduced performance or even partial failure of a subsystem 3-7, the automated journey can be continued at least until a safe parking space is reached.

Claims

1. Method for assisted, partially automated, highly automated, fully automated or driverless driving of a motor vehicle, by means of at least one control unit (2) for navigation and trajectory planning of an assisted, partially automated, highly automated, fully automated or driverless journey of the motor vehicle, and a plurality of subsystems (4 - 7), wherein the subsystems (4 - 7) implement driving dynamics requirements of the control unit (2), wherein at least one subsystem (4 - 7) is assigned a monitoring function by means of which the functionality of the subsystem (4 - 7) is determined, wherein the monitoring function transmits a currently possible performance capability to the control unit (2), wherein the control unit (2) adapts the navigation and trajectory planning depending on the transmitted performance capability such that the assisted, partially automated, highly automated, fully automated or driverless journey can be continued despite a reduced performance capability, wherein the subsystems (4-7) are a service brake system, a parking brake system, a steering system, a drive system and a transmission system, wherein, in the event of a transmitted reduced performance capability of a subsystem (4-7), the control unit (2) prepares at least one further system (9-11) such that this at least partially supports the subsystem (4-7), wherein a retarder and / or an exhaust brake and / or a recuperative braking of an electric machine is prepared in the event of a reduced performance capability of the service brake system, characterized in that road portions having predetermined characteristics are no longer taken into account in the navigation planning, wherein a predetermined characteristic is a gradient greater than a limit value.

2. Method according to claim 1, characterized in that at least one further subsystem (3) for supplying environmental data is present, to which a monitoring function is assigned which transmits the current performance capability.

3. Method according to any of the preceding claims, characterized in that the speed of the motor vehicle is reduced and / or a safety distance to be maintained from a motor vehicle driving ahead is increased.

4. Method according to any of the preceding claims, characterized in that other motor vehicles in the vicinity of the motor vehicle are informed about the reduced performance capability and / or the adapted driving style via a Car2Car interface (8).

5. Method according to any of the preceding claims, characterized in that depending on the reduced performance capability, the navigation planning determines a suitable stopping point.

6. Device (1) for assisted, partially automated, highly automated, fully automated or driverless driving of a motor vehicle, the device comprising at least one control unit (2) for navigation and trajectory planning and a plurality of subsystems (4 - 7), wherein the subsystems (4 - 7) are designed to implement driving dynamics requirements of the control unit (2), wherein at least one subsystem (4 - 7) is assigned a monitoring function which is designed to determine a functionality of the subsystem (4 - 7), wherein the monitoring function is designed to transmit a currently possible performance capability to the control unit (2), wherein the control unit (2) is designed such that, depending on the transmitted performance capability, the navigation and trajectory planning is adapted such that the assisted, partially automated, highly automated, fully automated or driverless journey can be continued despite a reduced performance capability, wherein the subsystems (4-7) are a service brake system, a parking brake system, a steering system, a drive system and a transmission system, wherein the control unit (2) is designed such that, in the event of a transmitted reduced performance capability of a subsystem (4-7), at least one further system (9-11) is prepared such that it at least partially supports the subsystem (4-7), wherein the subsystem (4) is a service brake, wherein the at least one further system (9-11) is designed as a retarder and / or exhaust brake and / or as a recuperative brake of an electric machine, characterized in that the control unit is designed in such a way that, in the event of a reduced performance capability of the service braking system, road portions having predetermined characteristics are no longer taken into account in the navigation planning, wherein a predetermined characteristic is a gradient greater than a limit value.

7. Device according to claim 6, characterized in that the device (1) has at least one further subsystem (3) for supplying environmental data, to which a monitoring function is assigned which is designed to transmit a currently possible performance capability to the control unit (2).