METHOD OF OPERATING A MOTOR VEHICLE DRIVEN ELECTRICALLY AT LEAST TEMPORARILY ON A ROADWAY, CONTROL UNIT FOR A MOTOR VEHICLE, AND CORRESPONDING MOTOR VEHICLE

Abstract

In a method of operating a motor vehicle driven electrically, at least temporarily, on a roadway, the motor vehicle is moved fully autonomously by a control unit in response to a command for automatic operating mode. After a charging arm of the motor vehicle has been extended, a lateral control of the motor vehicle is executed to bring the extended charging arm into electric contact with a charging line arranged at or on the roadway. As a result, electric energy provided from the charging line to the charging arm is used for charging an energy accumulator of the motor vehicle and/or operating a drive device of the motor vehicle for moving the motor vehicle. A longitudinal control of the motor vehicle is executed to thereby maintain a predefined longitudinal speed of the motor vehicle until a distance of the motor vehicle reaches a predefined minimum distance to a leading vehicle.

Claims

1. A method of operating a motor vehicle driven electrically at least temporarily on a roadway, said method comprising: moving the motor vehicle fully autonomously by a control unit in response to a command for automatic operating mode; executing a lateral control of the motor vehicle to electrically contact an extended charging arm with a charging line arranged at or on the roadway to generate electric energy for charging an energy accumulator of the motor vehicle and/or operating a drive device of the motor vehicle for moving the motor vehicle; and executing a longitudinal control of the motor vehicle to thereby maintain a predefined longitudinal speed until a distance of the motor vehicle reaches a predefined minimum distance to a leading vehicle.

2. The method of claim 1, further comprising switching to a convoy operating mode, when the motor vehicle has reached the minimum distance to the leading vehicle, and adjusting the longitudinal speed of the motor vehicle to match a speed of the leading vehicle to thereby maintain the minimum distance.

3. The method of claim 1, further comprising adjusting the longitudinal speed of the motor vehicle to a first default speed after issuance of the command for automatic operating mode, and adjusting the longitudinal speed to a second default value once the charging line has been contacted by the charging arm.

4. The method of claim 1, further comprising reducing the longitudinal speed of the motor vehicle relative to the leading vehicle in response to an indication of a further motor vehicle to merge so as to increase the distance to the leading vehicle and thereby provide space for the further motor vehicle.

5. The method of claim 1, further comprising increasing the longitudinal speed of the motor vehicle relative to a trailing vehicle in response to an indication of a further motor vehicle to merge so as to increase a distance to the trailing vehicle and thereby provide space for the further motor vehicle.

6. The method of claim 1, further comprising reducing the longitudinal speed of the motor vehicle relative to the leading vehicle in response to an indication by the leading vehicle for a lane change so as to increase the distance to the leading vehicle.

7. The method of claim 1, further comprising increasing the longitudinal speed of the motor vehicle relative to a trailing vehicle in response to an indication of the trailing vehicle for a lane change so as to increase the distance to the trailing vehicle.

8. The method of claim 1, further comprising sending a lane change signal to the leading vehicle in response to an indication by the motor vehicle for a lane change.

9. The method of claim 1, further comprising sending a lane change signal to a trailing vehicle in response to an indication by the motor vehicle for a lane change.

10. The method of claim 1, further comprising increasing the distance from the motor vehicle to the leading vehicle in response to an indication by the motor vehicle for a lane change.

11. The method of claim 2, further comprising selecting a motor vehicle of a plurality of motor vehicles in the convoy operating mode as guidance vehicle, and positioning the guidance vehicle as lead vehicle in a travel direction through lateral control and/or longitudinal control.

12. The method of claim 1, further comprising determining a distance of the motor vehicle to an upcoming road junction, when the motor vehicle operates in automatic operating mode and/or convoy operating mode, and triggering a warning signal to a driver of the motor vehicle, when the distance to the road junction falls below a predefined distance.

13. The method of claim 12, wherein the distance of the motor vehicle to the upcoming road junction is monitored by a navigation system or determined on information derived from the charging line.

14. A control unit for operating a motor vehicle driven electrically at least temporarily on a roadway, said control unit configured to move the motor vehicle fully autonomously in response to a command for automatic operating mode; execute a lateral control of the motor vehicle to electrically contact an extended charging arm with a charging line arranged at or on the roadway to generate electric energy for charging an energy accumulator of the motor vehicle and/or operating a drive device of the motor vehicle for moving the motor vehicle; and execute a longitudinal control of the motor vehicle to thereby maintain a predefined longitudinal speed until a distance of the motor vehicle reaches a predefined minimum distance to a leading vehicle.

15. A motor vehicle, comprising: a drive device configured to move the motor vehicle electrically at least temporarily on a roadway; and a control unit configured to operate the motor vehicle fully autonomously in response to a command for automatic operating mode; execute a lateral control of the motor vehicle to electrically contact an extended charging arm with a charging line arranged at or on the roadway to generate electric energy for charging an energy accumulator of the motor vehicle and/or operating the drive device for moving the motor vehicle; and execute a longitudinal control of the motor vehicle to thereby maintain a predefined longitudinal speed until a distance of the motor vehicle reaches a predefined minimum distance to a leading vehicle.

Description

BRIEF DESCRIPTION OF THE DRAWING

[0031] Other features and advantages of the present invention will be more readily apparent upon reading the following description of currently preferred exemplified embodiments of the invention with reference to the accompanying drawing, in which:

[0032] FIG. 1 is a schematic plan view of a motor vehicle according to the present invention during travel on a roadway along a charging line;

[0033] FIG. 2 is a schematic illustration of a first travel situation for the motor vehicle;

[0034] FIG. 3 is a schematic illustration of a second travel situation for the motor vehicle; and

[0035] FIG. 4 is a block diagram showing the relationship and operation of a control unit with components of the motor vehicle.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0036] Throughout all the figures, same or corresponding elements may generally be indicated by same reference numerals. These depicted embodiments are to be understood as illustrative of the invention and not as limiting in any way. It should also be understood that the figures are not necessarily to scale and that the embodiments may be illustrated by graphic symbols, phantom lines, diagrammatic representations and fragmentary views. In certain instances, details which are not necessary for an understanding of the present invention or which render other details difficult to perceive may have been omitted.

[0037] Turning now to the drawing, and in particular to FIG. 1, there is shown a schematic plan view of a motor vehicle according to the present invention, generally designated by reference numeral 1 during travel on a roadway 2. The roadway 2 includes several lanes 3, 4, here two, by way of example. Lane 3 is bounded by a road surface marking 5 and a charging line 6. By way of example, the charging line 6 is configured as a charging rail and provided to supply electric energy to the motor vehicle 1.

[0038] To receive electric energy from the charging line 6, the motor vehicle 1 includes a charging arm 7 which is swingably mounted upon the motor vehicle 1 or sidewall of the motor vehicle 1 for pivoting about a rotation axis 8. On its side distal to the motor vehicle 1, the charging arm 7 has a contact region 9 for realizing the electric contact with the charging line 6. The charging arm 7 is maintained under tension by a spring force from a spring element 10. The spring force is applied so as to urge the contact region 9 in the direction of the charging line 6 so that the contact region 9 seeks the electric contact with the charging line 6.

[0039] FIG. 2 depicts the motor vehicle 1 in a first travel situation in which the motor vehicle 1 is initially operated manually for example. After receiving a command for executing an automatic operating mode from a driver of the motor vehicle 1 or from a driver assist system, a control unit 20 (FIG. 4) of the motor vehicle 1 assumes control of the motor vehicle 1 to operate the motor vehicle 1 in a fully autonomous manner. The motor vehicle 1 is hereby steered via a lateral control to enable the charging arm 7 to come into electric contact with the charging line 6. The lateral control effects a shift of the motor vehicle 1 into the lane 3 along which the charging line 6 is positioned, i.e. the motor vehicle 1 is steered to change from lane 4 to lane 3, as indicated by arrow 11. The motor vehicle 1 thus merges into lane 3 behind a leading vehicle 12 or behind several vehicles 12 travelling ahead so that the motor vehicle 1 forms with the leading vehicles 12 a convoy 13. In addition, a longitudinal control of the motor vehicle 1 is executed during the fully autonomous driving mode so as to maintain a predefined longitudinal speed of the motor vehicle 1 until the latter has reached a predefined minimum distance to the leading vehicle 12.

[0040] When the motor vehicle 1 during the automatic operating mode has been steered to establish electric contact between the charging line 6 and the charging arm 7 and the distance of the motor vehicle 1 to the leading vehicle 12 corresponds to the minimum distance, the control unit 20 switches from automatic operating mode to a convoy operating mode. In the convoy operating mode, the longitudinal speed of the motor vehicle 1 is adjusted to match the speed of the leading vehicle 12 so as to maintain the minimum distance.

[0041] Fully autonomous operation is also maintained in the convoy operating mode. Thus, both the lateral control and the longitudinal control are assumed by the control unit 20. Lateral control is executed for example to keep or substantially keep constant the distance of the motor vehicle 1 to the charging line 6. Longitudinal control involves an adjustment of the longitudinal speed to maintain the distance to the leading vehicle 12 constant.

[0042] FIG. 3 depicts the motor vehicle 1 in a second travel situation in which a convoy 13 is formed by the motor vehicle 1, the leading vehicle 12, and a trailing vehicle 14, which all travel in lane 3. Advantageously, the vehicles 12, 14 can be operated in a same way as the motor vehicle 1. In this travel situation, the motor vehicle 1 wishes to depart from the convoy 13 and to change lane. This intent is indicated by turn signals, and a lane change signal is sent to the leading and trailing vehicles 12, 14.

[0043] To ensure clarity and to distinguish between the motor vehicle 1 and the other motor vehicles 12, 14, each the other motor vehicles has been designated in the description as “vehicle” for the sake of simplicity and convenience.

[0044] The fully autonomous driving mode for the vehicles 12, 14 and the motor vehicle 1 is then executed in such a way that the distances from the vehicles 12, 14 to the motor vehicle 1 increase, as indicated by double arrows 15, 16. When the respective distances are adequate, the motor vehicle 1 is able to depart the convoy 13, as indicated by arrow 17. The lane change is also implemented advantageously during fully autonomous driving mode of the motor vehicle 1, i.e. fully automatic through corresponding execution of both the lateral control and the longitudinal control.

[0045] A motor vehicle 1 according to the present invention and a method for operating such a motor vehicle allow realization of a fully autonomous electric driving mode of the motor vehicle 1 also over longer stretches. The motor vehicle 1 may operate only electrically, involving electric energy supplied by the charging line 6 during automatic operating mode and/or convoy operating mode.

[0046] At the same time, an energy accumulator of the motor vehicle 1 can be charged with electric energy. The fully autonomous driving mode of the motor vehicle 1 and the possibility for the motor vehicle 1 and the vehicles 12, 14 to travel in the convoy 13 results in a particularly energy-saving driving mode. In addition, as the driver of the motor vehicle 1 has the visual impression that the motor vehicle 1 is guided by the charging line 6, acceptance of the fully autonomous driving mode of the motor vehicle 1 is enhanced.

[0047] While the invention has been illustrated and described in connection with currently preferred embodiments shown and described in detail, it is not intended to be limited to the details shown since various modifications and structural changes may be made without departing in any way from the spirit and scope of the present invention. The embodiments were chosen and described in order to explain the principles of the invention and practical application to thereby enable a person skilled in the art to best utilize the invention and various embodiments with various modifications as are suited to the particular use contemplated.

[0048] What is claimed as new and desired to be protected by Letters Patent is set forth in the appended claims and includes equivalents of the elements recited therein: