WO2019091724A1

WO2019091724A1 - Method and driver assistance system for controlling the driving dynamics of a vehicle

Info

Publication number: WO2019091724A1
Application number: PCT/EP2018/078321
Authority: WO
Inventors: Tommy Ikonen; Roland Rehtanz; Costanza CASCELLI; Marcus Hiemer
Original assignee: Zf Friedrichshafen Ag
Priority date: 2017-11-10
Filing date: 2018-10-17
Publication date: 2019-05-16
Also published as: DE102017220004A1

Abstract

Disclosed are a method and a driver assistance system for controlling the driving dynamics of a trailing vehicle that follows a leading vehicle, wherein a distance between the trailing vehicle and the leading vehicle is determined, a directional angle between the trailing vehicle and the leading vehicle is determined, and the transverse dynamics of the trailing vehicle are controlled as a function of the distance and the directional angle.

Description

Method and driver assistance system for controlling the driving dynamics of a vehicle

Known methods for controlling the driving dynamics of a follower vehicle following a leader vehicle include determining a distance between the follower vehicle and the leader vehicle.

A regulation of the driving dynamics of a vehicle may also be understood to mean adapting, modifying or controlling the driving dynamics or driving dynamics characteristics of the vehicle during a drive of the vehicle.

Among the driving dynamics of a vehicle falls among other things the longitudinal dynamics of the vehicle. The longitudinal dynamics can also be defined as longitudinal movement or longitudinal regulation of the vehicle. For generating the longitudinal dynamics means for inducing a longitudinal movement, for example a drive or a brake, may be provided.

As a vehicle, basically any means of transporting people, goods or tools can serve. The vehicle may in particular be an agricultural machine, for example a tractor.

A lead vehicle can be understood as a leading vehicle. The Leader Vehicle may be a preceding vehicle in a vehicle fleet.

A follower vehicle may be another vehicle that follows the lead vehicle. Consequences may include both descendants of the follower vehicle behind the leader vehicle and ahead of the follower vehicle ahead of the leader vehicle. In other words, the following vehicle can travel in the direction of travel of the host vehicle behind or in front of this.

In determining a distance, a distance may be measured, estimated, or predetermined. Distance can also be understood as a distance or a distance.

Known driver assistance systems for controlling the driving dynamics of a following vehicle, which follows a lead vehicle, have or communicate with a distance meter for determining the distance between the following vehicle and the lead vehicle. A driver assistance system may be an electronic accessory in a vehicle to assist or replace the driver of the vehicle. The driver assistance system can partially autonomously or autonomously intervene in a drive, a control, for example gas or brake of the vehicle, or in a signaling device of the vehicle. The driver assistance system may also warn a driver through a man-machine interface prior to or during critical situations.

As a distance meter, a distance meter or a rangefinder may be provided.

Furthermore, an adaptive cruise control, which is also referred to as ACC (Adaptive Cruise Control) function, is known for regulating the longitudinal movement of a vehicle. Here, the distance of a behind-traveling vehicle is controlled to another vehicle with an engine intervention or a braking intervention. The steering of the following vehicle is actively carried out by a driver.

Solutions are provided to improve known methods for controlling vehicle dynamics and known driver assistance systems. In particular, solutions are to be provided which enable an autonomous following of a vehicle, that is to follow without driver intervention.

Such a solution for a method for controlling the driving dynamics of a follower vehicle comprises determining a direction angle from the follower vehicle to the leader vehicle and controlling the lateral dynamics of the follower vehicle based on the distance between the follower vehicle and the leader vehicle and the directional angle.

The control of the lateral dynamics may cause an autonomous following of one or more following vehicles, which may also be referred to as an automatic vehicle following function of the following vehicle. The follower vehicle or the following vehicles can thus drive automatically in or offset from the track of the leader vehicle.

For example, a farmer with a vehicle can drive from his yard to his field with a first vehicle, a car, or an agricultural machine, and a second vehicle can autonomously follow him without a driver on board. The farmer can also work in the field with an agricultural machine while the other agricultural machine follows it autonomously. The agricultural machines can do the same or different jobs in the field. It can be the same or to trade various agricultural machines. For example, a farmer can work with two tractors on the field at the same time.

The driving dynamics of a vehicle also affect the lateral dynamics of the vehicle. The lateral dynamics can be defined as transverse control, transverse movement or transverse alignment of the vehicle transversely to the longitudinal axis of the vehicle movement. To generate the transverse dynamics, means for causing the transverse movement or cornering, for example a steering, may be provided.

A direction angle can be defined as an angle between a reference direction and a target direction. The direction angle can therefore also be a direction indication. The reference direction may be a compass direction or a geodetic direction indication, in particular the direction angle may be an azimuth. The direction angle from the follower vehicle to the leader vehicle may also be defined as an angle in the follower vehicle, starting from a reference direction to the leader vehicle as a destination. In other words, the direction angle can specify the direction of travel of the following vehicle.

The solutions provided are based on the finding that autonomous driving of a follower vehicle can not be carried out solely on the basis of a longitudinal control, since a following along curved trajectories always requires a necessary and additional intervention in the lateral control by the driver.

A basic idea can be seen to provide for a follower vehicle in addition to a longitudinal dynamics control and a lateral dynamics control, both regulations in situ, that is, during vehicle travel, carried out and this no predetermined dynamic information must be specified. The information and data necessary for the longitudinal dynamics control and the lateral dynamics control can be obtained on the following vehicle itself during the following drive of the following vehicle. This is advantageous since a follow-up drive, in particular a steering drive, does not have to be preprogrammed. Rather, a lateral dynamics control of the follower vehicle can also be based on a new, previously unknown and thus not preprogrammable route of the host vehicle.

One embodiment consists of determining a position of the follower vehicle, determining a trajectory of the follower vehicle to be traversed for controlling the lateral dynamics. mik the follower vehicle, wherein the trajectory to be traversed depending on the position of the follower vehicle, the distance and the direction angle is set. To determine the trajectory to be traveled, the position of the lead vehicle can be determined. The position can be determined by polar attachment, interpolation or extrapolation. The trajectory to be traveled can be determined between the position of the follower vehicle and the position of the leader vehicle. The trajectory can be determined straightforward for straight-ahead travel or curved for cornering of the following vehicle. A position of the follower vehicle or the host vehicle may be understood to mean coordinates in a local or global coordinate system of the follower vehicle or the host vehicle. A local coordinate system in the follower vehicle can also be referred to as a co-moving coordinate system, that is, a coordinate system traveling with the follower vehicle. A position of one of the vehicles may also be a relative position with respect to the other vehicle. The trajectory to be traveled can also be defined as the travel path or route of the following vehicle. An automatic lateral dynamics control of the follower vehicle can thus enable an autonomous follow-up run of the follower vehicle.

A further embodiment consists in determining a trajectory of the lead vehicle and determining a trajectory of the following vehicle to be traversed for controlling the lateral dynamics of the following vehicle as a function of the particular trajectory of the lead vehicle of the lead vehicle, the distance and the direction angle. The trajectory of the lead vehicle can be traced by the follower vehicle. The descend can also be offset, whereby the trajectory of the follower vehicle to be traversed can be parallel to the trajectory of the leader vehicle. The trajectory of the lead vehicle can be formed by determining the position of individual positions along the travel path of the lead vehicle. The trajectory of the lead vehicle can be specified or determined only by the driving behavior of a driver. Multiple work tasks may be performed by multiple vehicles along a trajectory or along parallel trajectories with the same or different tools. By staggered or parallel driving, identical or different field work can be carried out in parallel. A further embodiment consists in rules of the driving dynamics of the following vehicle, wherein the driving dynamics of the following vehicle is controlled along or parallel to a trajectory of the lead vehicle. The driving dynamics of the following vehicle may be the longitudinal dynamics of the following vehicle and / or the lateral dynamics of the following vehicle. The rules of driving dynamics can, in addition to the rules of lateral dynamics also have the rules of longitudinal dynamics of the follower vehicle. It is also possible to determine the speed of the lead vehicle and to control the longitudinal dynamics of the following vehicle on the basis of this speed. A distance between the vehicles can thus be maintained constant during the drive of the vehicles along a trajectory.

A further embodiment consists in providing a sensor system for determining the distance and the direction angle on the following vehicle and / or on the leader vehicle. The sensor system may also include sensors that are not provided on any of the vehicles. As a sensor system, a position indicator can be provided on the leader vehicle and the following vehicle, respectively. In particular, in each case a satellite positioning system, for example a GPS receiver, may be provided on the vehicles. Alternatively or additionally, a sensor system may be provided only on one of the vehicles, in particular, the sensor system may also be arranged solely on the follower vehicle.

A further embodiment consists in determining the distance with a distance meter, which is arranged on the follower vehicle. The distance meter may be any transmitter and / or receiver or a transmitter for measuring a distance. The distance meter can perform distance measurements contactless or by means of a reflector on the target object. The distance meter may be a radar or radar sensor, which can measure the distance between the following vehicle and leader vehicle. The follower vehicle may thus have a radar-based vehicle following function for following the leader vehicle. With the distance meter, the distance to the lead vehicle can be adjusted. The distance meter can also be a laser device, a laser scanner, a photogrammetric system or a camera system. It is also conceivable that the distance measurement is performed using a combination of several sensors in order to improve the redundancy and / or the accuracy of the measurement. The distance meter can measure in a measuring direction or in a fan-like manner measure an opened measuring range. The distance meter can be pivotable in order to detect the leader vehicle in the measuring direction or in the measuring range spanned by the distance meter. The distance measurement or a position determination can be improved.

A pivotable distance meter provided on the following vehicle, in particular a radar device which can be pivoted to the left and to the right, can be pivoted relative to the lead vehicle on the following vehicle. The distance meter can be swiveled with a servomotor. With the distance meter so a specific area, such as the tail or a reflector can be targeted on the leader vehicle. The distance meter can also be operated by a driver by hand or automatically controlled by a control device or a software algorithm.

Based on a distance measurement to the lead vehicle, a target speed for the following vehicle can be calculated. When driving the following vehicle with the target speed, a constant distance between the vehicles can be maintained. For controlling the target speed, the engine drag torque for accelerating or decelerating, the gas or the brake can be operated.

A further embodiment consists in determining the directional angle with a directional meter, which is arranged on the follower vehicle. The distance meter can also serve as a direction indicator. In particular, both the distance and the direction angle can be determined with a radar device. Optionally, a measuring device for determining a reference direction may be provided for this purpose, for example a compass-type sensor or an inertial measuring unit (IMU) or a micro-electro-mechanical system (MEMS). With a directional meter on the follower vehicle so an angle between a reference direction and the leader vehicle can be determined.

A further embodiment consists in a regulation of the longitudinal dynamics of the following vehicle and in an autonomous steering of the following vehicle along or parallel to a trajectory of the lead vehicle. The regulation of the longitudinal dynamics of the following vehicle can be done on the basis of the distance. The steering may trigger a tangential movement of the follower vehicle along a trajectory. The steering can be achieved with a pivoting wheels of the follower vehicle. A steering system on On the basis of a trajectory, the aboard of the following vehicle can adjust the steering angle of the wheels as a setpoint so that the trajectory is followed.

A further embodiment consists in recognizing an object between the follower vehicle and the leader vehicle and considering the detected object when controlling the lateral dynamics of the follower vehicle. Objects may be obstacles that are bypassed by the follower vehicle. Objects can also be target objects, which are targeted by the follower vehicle, wherein the trajectory can also be deviated. In particular, other vehicles, people or animals, which are in the trajectory to be traversed by the following vehicle, can also be detected with a distance meter.

In addition, a stop of the follower vehicle may be provided if an obstacle or an object is in front of him or in the trajectory to be traversed by him. A signal may then be transmitted to a portable unit or an optical or audible signal may be output and displayed to the driver in the leader vehicle.

A solution for driver assistance system for controlling the driving dynamics of a follower vehicle is to provide a directional gauge for determining a direction angle from the following vehicle to the leader vehicle and to provide a lateral dynamics controller for controlling the lateral dynamics of the following vehicle based on the distance and the direction angle.

Activation of the driver assistance system on the follower vehicle may be activated by the driver who is in a cabin on the leader vehicle. The activation may be remotely controlled by a portable terminal or a portable unit, such as a mobile phone or a tablet.

The lateral dynamics controller may have a vehicle steering and be defined as an autonomous steering system. Another solution is a vehicle with such a driver assistance system.

Embodiments are explained below with reference to the schematic figures 1 to 3 on.

Fig. 1 shows a driver assistance system for a follower vehicle which a

Leader vehicle follows along the trajectory of the lead vehicle. FIG. 2 shows a driver assistance system for a follower vehicle, which follows a lead vehicle along a trajectory which is parallel to the trajectory of the lead vehicle.

3 shows method steps for a method for regulating the driving dynamics of a follower vehicle.

FIG. 1 shows a follower vehicle 10 and a leader vehicle 20. The follower vehicle 10 follows the leader vehicle 20 along a trajectory T10, which corresponds to a trajectory T20 of the leader vehicle 20.

At the front of the follower vehicle 10, a distance meter 30 and a direction indicator 40 is arranged. The distance meter 30 measures a distance d to the lead vehicle 20 and the direction meter 40 determines a direction angle a starting from a reference direction 42 to the lead vehicle 20.

On the roof of the follower vehicle 10, a position gauge 12 is also provided, which detects a position P10 of the follower vehicle 10. Also on the roof of the lead vehicle 20, a position gauge 22 is also provided, which detects a position P20 of the lead vehicle 20. By means of calibration, each position of another component on a vehicle 10, 20 can be determined.

Further located on the follower vehicle 10 is a lateral dynamics controller 50 which controls the lateral dynamics of the follower vehicle 10. This can in particular communicate with the front wheels 14 of the follower vehicle 10 and drive and pivot them.

FIG. 2 also shows a follower vehicle 10 and a leader vehicle 20. The follower vehicle 10 follows the leader vehicle 20 along a trajectory T10, which is offset and parallel to the trajectory T20 of the leader vehicle 20.

At the front of the follower vehicle 10, a distance meter 30 and a direction indicator 40 is arranged. The distance meter 30 measures fan-like within an opening angle b a distance d (not shown) to the lead vehicle 20 and the direction meter 40 then determines a direction angle a (not shown) to the lead vehicle 20th

FIG. 3 shows method steps for a method for regulating the driving dynamics of a follower vehicle. Provided as method steps are determining S1 a distance d between the follower vehicle 10 and the leader vehicle 20, determining S2 a direction angle a from the follower vehicle 10 to the leader vehicle 20, and determining S3 a position P10 of the follower vehicle 10.

As a method step, it is then further provided that S4 defines a trajectory T10 of the follower vehicle 10 based on the steps S1, S2 and S3.

As further method steps are then further provided a rules S5 of the lateral dynamics of the follower vehicle 10, a rules S6 of the longitudinal dynamics of the follower vehicle 10 and based on these steps a rules S7 of the driving dynamics of the follower vehicle 10th

REFERENCE CHARACTERS

10 follower vehicle

12 position indicator follower vehicle

14 front wheels follower vehicle

20 lead vehicle

22 position indicator lead vehicle

30 distance meters

40 directional meters

42 reference direction

50 lateral dynamics controller

a directional angle

d distance

P10 position follower vehicle

P20 position master vehicle

T10 trajectory following vehicle

T20 trajectory Leader vehicle

51 determining a distance

52 Determining a directional angle

53 Determining a position

54 Defining a trajectory

55 Rules of lateral dynamics of the following vehicle

56 rules of the longitudinal dynamics of the follower vehicle

57 Rules of the driving dynamics of the following vehicle

Claims

claims

A method of controlling (S7) the driving dynamics of a follower vehicle (10) following a leader vehicle (20), comprising determining (S1) a distance (d) between the follower vehicle (10) and the leader vehicle (20) characterized by

Determining (S2) a directional angle (a) of the follower vehicle (10) to the leader vehicle (20) and rules (S5) of the lateral dynamics of the follower vehicle (10) on the basis of the distance (d) and the direction angle (a).

2. The method according to claim 1, characterized by determining (S3) a position (P10) of the follower vehicle (10), determining (S4) a trajectory (T10) of the follower vehicle (10) to be controlled for regulating (S5) the lateral dynamics of the follower vehicle (10 ), wherein the trajectory to be traversed (T10) is determined as a function of the position (P10) of the following vehicle (10), the distance (d) and the directional angle (a).

3. The method according to any one of claims 1 or 2, characterized by determining a trajectory (T20) of the leader vehicle (20) and defining a retractable trajectory (T10) of the follower vehicle (10) for regulating (S5) the lateral dynamics of the follower vehicle (10) Dependence of the determined trajectory (T20) of the lead vehicle (20), the distance (d) and the direction angle (a).

4. The method according to any one of claims 1 to 3, characterized by rules (S7) of the driving dynamics of the follower vehicle (10), wherein the driving dynamics of the follower vehicle (10) along or parallel to a trajectory (T20) of the lead vehicle (20) is controlled.

5. The method according to any one of claims 1 to 4, characterized by providing a sensor system for determining the distance (d) and the direction angle (a) on the follower vehicle (10) and / or on the lead vehicle (20).

6. The method according to any one of claims 1 to 5, characterized by determining (S1) of the distance (d) with a distance meter (30) which is arranged on the follower vehicle (10).

7. The method according to any one of claims 1 to 6, characterized by determining (S2) of the direction angle (a) with a direction indicator (40) which is arranged on the follower vehicle (10).

8. The method according to any one of claims 1 to 7, characterized by rules (S6) of the longitudinal dynamics of the follower vehicle (10) and autonomous steering of the follower vehicle (10) along or parallel to a trajectory (T20) of the lead vehicle (20).

9. The method according to any one of claims 1 to 8, characterized by recognizing an object between the follower vehicle (10) and the leader vehicle (20) and taking into account the detected object when controlling the lateral dynamics (S5) of the follower vehicle (10).

A driver assistance system for controlling the driving dynamics of a follower vehicle (10) following a leader vehicle (20), comprising a range finder (30) for determining the distance (d) between the follower vehicle (10) and the leader vehicle (20), characterized by Direction indicator (40) for determining a direction angle (a) from the follower vehicle (10) to the leader vehicle (20) and a lateral dynamics controller (50) for controlling the lateral dynamics of the follower vehicle (10) on the basis of the distance (d) and the direction angle (a).

11. vehicle with a driver assistance system according to claim 10.