Method, device and computer program product for moving a vehicle in tension

Abstract

The invention relates to a method for tensilely moving a vehicle (10) having a drive unit (11) for accelerating the vehicle (10) and a brake unit (12) for braking the vehicle (10), the method having the steps of generating a tensile drive torque by means of the drive unit (11), generating a brake torque by means of the brake unit (12) in order to compensate for the tensile drive torque and thereby to generate a tensile torque in the vehicle (10), and braking the vehicle (10) by means of a reduction of the drive torque. The invention also relates to a device (13) and a computer program product (14) for carrying out the method according to the invention, and to a storage medium (15) on which the computer program product according to the invention is stored.

Description

[0001] This invention relates to a method and apparatus for accurately maneuvering a vehicle at a low speed in a confined space. The invention also relates to a computer program product and a storage medium for performing this method, the computer program product being stored on the storage medium.

[0002] Vehicle maneuvers must be performed with exceptional slowness and precision in various situations. This applies, for example, to maneuvers such as parking, driving over curbs, and attaching a vehicle to a tow bar. To enable slow and precise vehicle movement without errors, driving skills and / or assistive electronics are required. Furthermore, it is desirable to achieve the highest possible driving comfort during maneuvers. Known driver assistance systems can be found, for example, in CN 107237848B and FR 2856449 A1.

[0003] In known systems, attempts are typically made to regulate vehicle acceleration through corresponding driving torque and braking or deceleration through braking torque. However, known solutions always involve a certain degree of delay. Universal brakes, as deceleration actuators, are relatively imprecise and have significant delays because the physical volume must move before the desired braking effect takes effect. Furthermore, braking effectiveness is affected by various environmental factors such as ambient temperature, which diminishes the adjustability and makes it even more difficult to achieve.

[0004] The technical problem to be solved by the present invention is to at least partially address the above-mentioned problems. In particular, the present invention aims to provide a method and apparatus for moving a vehicle as accurately as possible within a small space.

[0005] The aforementioned technical problems are solved by means of the method according to the invention, the apparatus according to the invention, the computer program product according to the invention, and the storage medium according to the invention. Other advantages of the invention are given by preferred embodiments, the specification, and the drawings. Herein, the features described in connection with the method are of course also applicable to combinations with the apparatus according to the invention, the computer program product according to the invention, and the storage medium according to the invention, and vice versa; therefore, the disclosure of various aspects of the invention is always mutually referenced and / or can be mutually referenced.

[0006] According to a first aspect of the present invention, a method for tensioning the movement of a vehicle is provided, the vehicle having a drive unit for accelerating the vehicle and a braking unit for braking the vehicle. The method comprises the following steps:

[0007] - Tensioning driving torque is generated through the drive unit.

[0008] - A braking torque is generated by the braking unit to compensate for the tensioning drive torque and thereby generate a tensioning torque in the vehicle, and

[0009] - Braking the vehicle by reducing the driving torque.

[0010] By utilizing a defined tension, or corresponding preload torque, between the driving torque and braking torque, accurate and precise regulation of acceleration and the resulting vehicle speed and mileage can be achieved. This avoids delay losses caused by pressure buildup in the braking unit. The low delay during braking also contributes to a high level of driving comfort and safety.

[0011] The method according to the invention is particularly suitable for shunting and / or parking, especially for electronically assisted shunting and / or parking of vehicles. In these driving maneuvers, rapid and precise stopping is crucial. Currently, particularly high demands are placed on the accuracy of brake actuators during assisted shunting and / or parking. Using the proposed method, it is possible to ensure adherence to, for example, the maximum stopping distance desired by the parking function.

[0012] Tensioning a vehicle can be understood as causing the vehicle to move in a manner in which tensioning drive torque and braking torque are simultaneously applied to relevant components of the vehicle with the same magnitude but different positive and negative signs, while the vehicle moves with an additional drive torque. However, braking torque can be understood as a positive braking torque. Compensation for tensioning drive torque can be understood as generating braking torque to at least this extent, such that the braking torque balances the tensioning drive torque. Therefore, the braking torque has at least the magnitude of the tensioning drive torque with a different sign. The reduced drive torque for braking the vehicle can be understood as tensioning drive torque or additional drive torque, which can be referred to as acceleration drive torque. Instead of generating acceleration drive torque, the tensioning drive torque can also be increased to a value exceeding that generated for the desired tensioning torque. Both tensioning drive torque and acceleration drive torque are generated by the drive unit and are named differently herein, especially for better distinction of the different torque values. Braking torque can also be understood as tensioning braking torque. Therefore, braking torque should not be limited to the idea of ​​stopping the vehicle by means of braking torque. Rather, the braking torque according to the invention should be used to generate tension torque.

[0013] Vehicle braking can be understood as the braking and / or deceleration of the vehicle, possibly until the vehicle comes to a stop. That is, braking should not be limited to being considered a pure braking process in which only braking torque is at work. Crucially within the scope of this invention, during vehicle braking or deceleration, both the braking torque and the tensioning drive torque, i.e., the tensioning torque, are engaged as always as possible. The braking unit particularly includes the vehicle's brakes, especially in the form of friction brakes.

[0014] Similar to the tensioning motion of a vehicle, one can imagine a driver with one foot on the brake and the other on the accelerator pedal, or gas pedal, to counteract the applied braking torque, thus keeping the resulting vehicle acceleration and speed constant. Therefore, as the vehicle increases speed, a braking torque can be applied, and the driving torque increases by the same "negative" amount in parallel. Now, if, for example, a customer function in the category of parking assistance or trailer assistance for attaching the vehicle to a trailer hitch, requires a negative target acceleration, the vehicle can be quickly, precisely, and without delay to a stop simply by removing the driving torque.

[0015] Preferably, braking torque is requested or generated for an extended period, as long as the vehicle is in motion and / or until the vehicle stops again. The braking torque can be added to the existing drive torque and / or acceleration drive torque, and during adjustment, the braking torque is accompanied by a constant offset on the drive path. Thus, the vehicle's drivetrain can resist the operation of the braking unit in a defined manner. This seemingly paradoxical process yields the decisive advantage that, as described above, by removing the drive torque, the vehicle can be braked particularly quickly and without delay. Furthermore, there are advantages such as higher braking efficiency in terms of achievable pressure gradients and higher drive setting accuracy by moving to a more adjustable operating point beyond minimum load.

[0016] To end the shunting and / or parking process, the vehicle is first brought to a stop by a negative target acceleration, or braking. Once the vehicle stops, the tension, or the tensioning torque, can be reduced. Preferably, the braking torque is set to always be greater than the tensioning drive torque. Therefore, it can be ensured that the vehicle can reliably remain in the desired position even after braking has ended and / or when the vehicle has come to a stop. Furthermore, this method always prevents unintended acceleration of the vehicle.

[0017] The tensioning drive torque and the braking torque can be generated simultaneously or sequentially. That is, compensating for the tensioning drive torque with the braking torque can also be understood as compensating for the braking torque with the tensioning drive torque. Preferably, the braking torque is generated first, and then, or almost simultaneously, preferably while the braking torque is still being generated, the tensioning drive torque is generated. During the acceleration process used to accelerate the vehicle, the braking torque and the tensioning drive torque can be established simultaneously to generate the tensioning torque.

[0018] According to another embodiment of the invention, in the method, the vehicle can be accelerated by an acceleration drive torque, and then a tension torque can be generated. Therefore, a desired acceleration and / or desired speed can be set first, and then the desired tension torque can be applied. This approach offers the advantage that a direct transition to tensioned operation and subsequent vehicle braking adjustments can be made without stopping the vehicle. In practice, customer functions such as intelligent parking assist or trailer assist can be activated first. Once the function specifies a positive target acceleration and the vehicle begins or has already accelerated, the tension torque can be generated.

[0019] Furthermore, in the method according to the invention, a tension torque can be generated when the vehicle stops, followed by an acceleration drive torque for accelerating the vehicle. Therefore, it is particularly effective in preventing unintended acceleration and / or unexpected braking of the vehicle during driving maneuvers. During the generation of the tension torque, the braking torque or tension drive torque may be excessively high for a short period, potentially leading to a corresponding braking or acceleration process. This can be prevented or at least reduced by establishing the tension torque first when the vehicle stops, especially in cases with a predefined excessively high braking torque, i.e., a braking torque that is always slightly greater than the tension drive torque at least during the stopping period.

[0020] In the method according to the invention, the braking torque can also be changed according to the varying adjusted tension drive torque and / or the varying adjusted acceleration drive torque. That is, the braking torque can be changed and / or adjusted depending on how the tension drive torque and / or the acceleration drive torque changes or is changed. The braking torque and the resulting tension torque can be calculated based on the slope, or rather, based on the slope the vehicle is on or the slope in which the vehicle is moving. Therefore, simply by reducing the drive torque, it is possible to reliably decelerate or brake the vehicle to a stop. The related changes and / or adjustments to the braking torque can be understood as dynamically adjusting the braking torque according to the varying adjusted and / or changing tension drive torque and / or the varying adjusted and / or changing acceleration drive torque. Furthermore, the tension drive torque and / or the changing acceleration drive torque can be dynamically changed or adjusted based on the adjusted and / or changing braking torque. Therefore, for example, when the ground has different slopes and braking or acceleration is required, different torques can be continuously adapted to the corresponding driving conditions. If the set tension torque is insufficient, additional braking torque can be requested at the braking unit, for example.

[0021] It may also be advantageous that, in the method according to the invention, the tension torque is reduced when the vehicle stops. Therefore, unexpected acceleration and / or braking processes can be prevented, at least as much as possible, during vehicle operation. Consequently, corresponding driving adjustments can be performed with high driving comfort and high driving safety. It may also be advantageous to limit the vehicle speed to less than 2 km / h, especially less than 1 km / h, during the tensioning operation. Therefore, it is particularly advantageous to eliminate the need to change the set tension torque during driving.

[0022] According to another embodiment of the invention, in the method, for driving maneuvers used to position the vehicle, particularly for maneuvering and / or parking, the vehicle can be accelerated to a speed of less than 10 km / h, particularly less than 5 km / h, in a predefined holding position by means of an acceleration driving torque. This ensures that the tension torque becomes sufficiently small to prevent, for example, damage to the vehicle and / or to avoid uncontrolled movement of the vehicle. For example, if the vehicle is to be moved with tension throughout the parking process guided by intelligent parking assistance, the tensioned movement of the vehicle can be limited to a maximum of 4 km / h. Here, after activating parking assistance, a basic tension torque can be established during the starting process. During the acceleration process, the tension torque can be continuously increased until the basic tension torque has been reached. As mentioned above, this process can be increased to a value determined for the application based on the gradient.

[0023] Furthermore, in the method according to the invention, in order to generate the tensioning torque, a gradient braking torque can be generated with a torque greater than the tensioning drive torque. That is, the braking torque is established or generated faster and / or stronger than the tensioning drive torque. Therefore, it is particularly effective in preventing unintended acceleration of the vehicle. Furthermore, this can avoid accidents that may occur, for example, due to late braking and / or excessive acceleration. Possible short-term vehicle stops can be taken into account by gradient limiting the braking torque, which leads to a continuous increase or rise in the tensioning torque. It may also be advantageous to set a gradient limit for the drive torque that is larger than the braking torque.

[0024] Additionally or alternatively, it may be advantageous that, in the method according to the invention, the braking torque is reduced in a decreasing gradient with a torque smaller than the tensioning drive torque, so as to reduce or lower the tensioning torque. Therefore, it is also possible to ensure that there is always sufficient braking torque to reliably prevent unintended acceleration of the vehicle. Furthermore, reliable stopping of the vehicle can thus be ensured. Alternatively and / or additionally, in the method according to the invention, to generate the tensioning torque, the braking torque can be started in time before the tensioning drive torque is generated. In other words, the drive torque can be established with a time delay relative to the braking torque. Here, a gradient limit on the braking torque can also be implemented to avoid undesirable acceleration of the vehicle. To reduce the tensioning torque, the braking torque can also be reduced in time after the tensioning drive torque is reduced. Thus, the advantages already mentioned can be achieved in a similar manner.

[0025] According to another aspect of the invention, a device for tensioning a vehicle according to the method described above is provided. The device includes a drive unit for accelerating the vehicle, a braking unit for braking the vehicle, and an adjustment unit for adjusting the tension torque by means of the drive unit and the braking unit, and for braking the vehicle by means of the braking unit. Therefore, the device according to the invention has the same advantages as described in detail with reference to the method according to the invention. The braking unit has a friction brake, which is particularly common for vehicles, especially road vehicles such as cars or trucks. The acceleration unit preferably has a universal drivetrain or is designed as part of a drivetrain. The adjustment unit particularly has a universal vehicle control device or is designed as part of such a vehicle control device.

[0026] Furthermore, a computer program product is provided, comprising instructions that, when implemented by a computer, cause the computer to perform the method described in the detailed description using the apparatus as described above. The computer may be considered a vehicle control device, may include part of a vehicle control device, or may have other functional components besides a vehicle control device. The computer program product can be implemented as computer-readable instruction code in any suitable programming language and / or machine language (e.g., JAVA, C++, C#, and / or Python). The computer program product can be stored on a computer-readable storage medium such as a data disk, removable drive, volatile or non-volatile memory, or built-in memory / processor. The instruction code can be programmed onto a computer or other programmable device such as a vehicle control device to perform the desired function. Furthermore, the computer program product can be provided and / or offered on a network such as the Internet, and users can download it from the network on demand. The computer program product can be implemented and / or implemented not only by means of software but also by means of one or more specific electronic circuits (i.e., in hardware) or any hybrid form (i.e., by means of software components and hardware components).

[0027] Within the scope of this invention, a computer-readable storage medium is also proposed, on which a computer program product, as described in detail above, is stored. The storage medium is provided, in particular, in the form of a non-volatile storage medium. Therefore, the storage medium and the computer program product according to the invention possess the advantages described above.

[0028] Further improvements to the invention are given in the following description of various embodiments of the invention, which are schematically illustrated in the accompanying drawings. All features and / or advantages arising from the claims, description, or drawings, including structural details and spatial arrangements, are essential to the invention both in themselves and in their various combinations.

[0029] In the attached diagram:

[0030] Figure 1 The illustration shows a method for illustrating a first embodiment of the present invention.

[0031] Figure 2 A flowchart illustrating the method according to the first embodiment is shown.

[0032] Figure 3 Illustrations are shown illustrating a method according to a second embodiment of the present invention, and

[0033] Figure 4 A block diagram is shown for representing a storage medium on which a computer program is stored according to the present invention.

[0034] Components with the same function and mode of operation are respectively given the same reference numerals in the accompanying drawings.

[0035] Figure 1 A vehicle 10 is shown, which has a drive unit 11 for accelerating the vehicle 10 and a braking unit 12 for braking the vehicle 10. The vehicle 10 is designed in the form of a sedan. The drive unit 11 includes the engine and other drive components of the vehicle 10, and the braking unit 12 includes friction brakes for the vehicle 10. The vehicle 10 also has a vehicle control unit 20, which has adjustment units for controlling the drive unit 11 and the braking unit 12. In addition, the vehicle 10 has a trailer coupling 17, to which the tow bar 18, or the coupling section of the tow bar 18 of the trailer 16, can be fixed.

[0036] refer to Figure 1 and Figure 2The method for tensioning the vehicle 10 to connect the trailer coupling 17 to the drawbar 18, or to connect the vehicle 10 to the trailer 16, is then described. In the first step S1, a braking torque is first generated by the braking unit 12. Furthermore, in step S2, a tensioning driving torque is generated by the drive unit 11. Steps S1 and S2 may also be performed simultaneously, substantially simultaneously, or at least partially simultaneously in reverse order. The braking torque and driving torque are generated as similarly in magnitude and with different positive and negative signs as possible, such that the braking torque and driving torque compensate for or balance each other to generate a tensioning torque in the vehicle 10. In the third step S3, an acceleration driving torque is now generated to accelerate the vehicle 10 to a predefined shunting speed, approximately 2 km / h in this embodiment. In the fourth step S4, the vehicle 10 is now braked within the scope of the shunting process by reducing the driving torque, particularly reducing the acceleration driving torque or exceeding the driving torque used to generate the desired tensioning torque. The braking process is performed, especially when the trailer coupling 17 is on the drawbar 18 and / or the drawbar 18 is close to a predefined distance.

[0037] The braking torque can be changed according to the varying adjusted tension drive torque and / or the varying adjusted acceleration drive torque. To generate the tension torque according to steps S1 and S2, a gradient braking torque is generated with a torque greater than the tension drive torque. Furthermore, the braking torque is generated shortly before the tension drive torque is generated. To reduce the tension torque, the braking torque is reduced with a torque smaller than the tension drive torque. Furthermore, the braking torque is reduced after the tension drive torque has decreased. The adjustment unit (not shown) of the vehicle control device 20 is configured to perform this method using existing vehicle components. To perform this method, in Figure 1 The vehicle shown has a device 13, which includes a drive unit 11, a braking unit 12, and an adjustment unit.

[0038] refer to Figure 3 Another embodiment of the method is described, in which vehicle 10 will drive over a curb or kerb on a slope. Here, the tension torque should first be set such that vehicle 10 can be maintained accordingly solely by the braking torque set during tensioning, so that the withdrawal of the driving torque causes vehicle 10 to stop under any circumstances. In this case, the maximum driving speed is limited to 4 km / h. A speed of 0.5 m / s is considered here. 2 The vehicle may decelerate. This results in a force of 1050N with a vehicle mass of 2100kg. This generates a tension torque of approximately 327Nm. This value should now be kept applicable so that it can be adapted to another vehicle project. Now, if we assume that the vehicle is to stop not far from the curb from a driving speed of 4km / h or 1.1m / s, it must stop at 0.5m / s.2 The vehicle is braked by deceleration. This takes approximately 2.2 seconds. Depending on the slope in which the vehicle 10 is moving, the tension torque can be adjusted accordingly to ensure a stop when the drive torque is turned off alone. In the current situation, the additional torque required on this slope can be calculated as follows. First, determine the climbing resistance, which has a value of approximately 1580 N. Now, to determine or calculate the required tension torque from this, the climbing resistance can be multiplied by the wheel radius, and the tension torque in the plane can be added. This yields a tension torque of approximately 818 Nm.

[0039] However, the total torque of the tensioning drive torque and the acceleration drive torque should not exceed 2 m / s². 2 The equivalent. If the customer's function requires a maximum acceleration of 0.5 m / s² for parking assistance. 2 Then the tensioning or tensioning torque is limited to 1.5 m / s². 2 The equivalent of this is approximately 980 Nm of tension torque. This ensures that when the braking torque cannot be set in a fault condition, the resulting acceleration will not cause uncontrolled and / or uncontrollable movement of the vehicle 10. Furthermore, it can be configured to shut off the drive torque as quickly and / or directly as possible upon detection of a fault condition. Using this method, the vehicle 10 can safely and accurately move to and cross the curb 19 even on an incline. The forces and torques generated during crossing the curb can be calculated and adjusted accordingly in a similar manner to those described in detail above regarding inclines.

[0040] Figure 4 A computer-readable non-volatile storage medium 15 is shown, having a computer program product 14 stored thereon. The computer program product 14 includes instructions that, when implemented by a computer such as a vehicle control unit 20, cause the computer to implement the methods described in detail above in the vehicle 10.

[0041] In addition to the embodiments shown, the present invention allows for further design principles. That is, the present invention should not be considered as limited to the embodiments described with reference to the accompanying drawings.

[0042] List of reference numerals

[0043] 10 vehicles

[0044] 11 Drive Unit

[0045] 12 Braking Units

[0046] 13 devices

[0047] 14 Computer program products

[0048] 15 Storage Media

[0049] 16 trailers

[0050] 17 Trailer Coupling

[0051] 18. Towing bar

[0052] 19. Roadside stones

[0053] 20 Vehicle control devices

Claims

1. A method for tensioning a vehicle (10), the vehicle having a drive unit (11) for accelerating the vehicle (10) and a braking unit (12) for braking the vehicle (10), the method comprising the steps of: - A tensioning driving torque is generated by the drive unit (11). - A braking torque is generated by the braking unit (12) to compensate for the tensioning drive torque and thereby generate a tensioning torque in the vehicle (10), and - Braking the vehicle (10) by reducing the acceleration driving torque, in, To reduce the tension torque, the braking torque is reduced by a gradient with a torque smaller than the tension driving torque.

2. The method according to claim 1, Its features are, The vehicle (10) is accelerated by the acceleration driving torque, and then the tensioning torque is generated.

3. The method according to claim 1, Its features are, A tensioning torque is generated when the vehicle (10) stops, and then an acceleration driving torque is generated to accelerate the vehicle (10).

4. The method according to any one of claims 1 to 3, Its features are, The braking torque is changed according to the varying tension driving torque and / or the varying acceleration driving torque.

5. The method according to any one of claims 1 to 3, Its features are, The tension torque is reduced when the vehicle (10) stops.

6. The method according to any one of claims 1 to 3, Its features are, For driving maneuvers used to position the vehicle (10), the vehicle (10) is accelerated to a speed of less than 10 km / h in a predetermined holding position by means of an acceleration driving torque.

7. The method according to any one of claims 1 to 3, Its features are, In order to generate the tension torque, a gradient is generated with a torque greater than the tension driving torque to generate the braking torque.

8. The method according to any one of claims 1 to 3, Its features are, In order to generate the tension torque, the braking torque is generated before the tension driving torque is generated.

9. The method according to any one of claims 1 to 3, Its features are, In order to reduce the tension torque, the braking torque is reduced after the tension driving torque is reduced in time.

10. A device (13) for tensioning a vehicle (10) according to any one of claims 1 to 9, the device having a drive unit (11) for accelerating the vehicle (10), a braking unit (12) for braking the vehicle (10), and an adjustment unit for adjusting the tension torque by means of the drive unit (11) and the braking unit (12) and for braking the vehicle (10) by means of the braking unit (12).

11. A computer program product (14) comprising instructions that, when implemented by a computer, cause the computer to implement the method according to any one of claims 1 to 9 using the apparatus (13) according to claim 10.

12. A computer-readable storage medium (15) having a computer program product (14) according to claim 11 stored thereon.

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