Control Based on Reference Sensor Data

Abstract

To improve control of a vehicle that autonomously or semi-autonomously travels.SOLUTION: A method for controlling a vehicle (101) includes the steps of: manually controlling the vehicle (101) while storing sensor data from at least one sensor; and autonomously controlling the vehicle (101) while acquiring sensor data from at least one sensor and comparing the sensor data to the stored sensor data.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a control method according to the upper concept part of claim 1, a computer program according to claim 8, and a data processing device according to claim 9.

Background Art

[0002] Patent Document 1 (German Patent Application Publication No. 3408720) discloses a trackless floor conveying system for transporting small packages in a warehouse. The floor conveying system is composed of a motor vehicle having a steering drive and a guiding system for guiding individual vehicles on a predetermined lane. In order that individual vehicles can travel on arbitrarily selectable lanes without a time-consuming setup operation, the guiding system has a plurality of fixedly arranged transmitters and receivers with computers installed on each vehicle, or transmitters with receivers installed on the vehicles and at least two receivers with computers fixedly arranged above the floor. Each lane of each vehicle is learned by manually controlling each vehicle when a human operator travels on these lanes. The data generated in the process is used as reference data. Thereby, during subsequent travel, the vehicle position is determined by comparing with current sensor data, and the vehicle is navigated along a predetermined lane.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] An object of the present invention is to improve the control of a vehicle that travels autonomously or semi-autonomously.

Means for Solving the Problems

[0005] This problem is solved by the control method according to claim 1, the computer program according to claim 8, and the data processing device according to claim 9. Preferred configurations are described in the dependent claims and will become apparent from the embodiments described below and shown in the drawings.

[0006] The control method according to the present invention is used to control a vehicle that travels autonomously or semi - autonomously. A vehicle that travels autonomously or semi - autonomously has one or more control devices, and these control devices enable the vehicle to be controlled at least partially autonomously, i.e., without a human operator.

[0007] The vehicle controlled by the control method according to the present invention is preferably an industrial truck such as a forklift.

[0008] In the control method of the present invention, first, it is assumed that the vehicle is manually controlled, i.e., controlled by a human operator, for example, a driver or a person who affects the vehicle from outside the vehicle using remote control. During that time, sensor data from at least one sensor in the vehicle is stored.

[0009] In the present invention, the stored sensor data can be used as reference data for autonomous driving. In the corresponding method step, it is assumed that the vehicle is autonomously controlled, i.e., controlled without a human operator. During that time, sensor data from at least one sensor is acquired. The acquired data is compared with the stored data.

[0010] By the control method according to the present invention, driving is manually learned and then the driving is autonomously reproduced based on the comparison of sensor data. This is advantageous compared to known methods in that the already installed vehicle sensors can be used. There is no need to provide additional sensors to identify the vehicle position in the surrounding environment.

[0011] In a preferred embodiment, it is desirable to match as closely as possible the stored sensor data and the sensor data acquired during the autonomous control of the vehicle. The vehicle is autonomously controlled so that the acquired sensor data matches the recorded sensor data. That is, the vehicle is autonomously controlled so that the deviation between the acquired sensor data and the stored sensor data is as small as possible. This can be achieved, for example, by measuring the deviation. As a measurement of the deviation, for example, the arithmetic mean of the differences between the individual acquired sensor data and the stored sensor data corresponding to each other is suitable. Preferably, the vehicle is autonomously controlled so that the deviation becomes zero, that is, the acquired sensor data matches the stored sensor data.

[0012] In an even more preferred embodiment, the sensor data stored while the vehicle is manually controlled and the sensor data acquired during autonomous driving and compared with the recorded sensor data relate to at least one amount of movement in the vehicle or a part of the vehicle. Preferably, only the amount of movement of the vehicle or a part of the vehicle is acquired and compared.

[0013] The amount of movement of the vehicle or a part of the vehicle is a physical quantity that at least partially describes the movement of the vehicle or a part of the vehicle. Suitable sensors include, for example, an accelerator pedal sensor, a hydraulic pressure sensor, a wheel speed sensor, or a steering angle sensor. The accelerator pedal sensor detects the position of the accelerator pedal. The driving force of the vehicle is affected by the position of the accelerator pedal. The hydraulic pressure sensor detects the position of at least a part of the hydraulic pressure in the vehicle. Instead of such a hydraulic pressure sensor, the position of a part of the hydraulic pressure, particularly the position of the lifting (lift) device, can also be determined based on the operation of the valve corresponding to the relevant hydraulic cylinder. The wheel speed sensor of the vehicle measures the wheel speed of the vehicle. The steering angle sensor detects the steering angle, that is, the rotation angle of the steering in the vehicle, or the steering angle of the wheel of the steerable axle in the vehicle.

[0014] This embodiment is advantageous because the sensors for detecting the amount of movement are relatively inexpensive. Many such sensors are already installed in conventional vehicles and do not need to be retrofitted. In particular, in this embodiment, it is not necessary to use expensive optical sensors.

[0015] In a more preferred embodiment, a manually controlled operation sequence is reproduced based on the stored sensor data. The manually controlled operation sequence is the operation sequence that the vehicle executes during manual control. The operation sequence means a series of movements of the vehicle with respect to a fixed reference system such as a road or a building, and / or a series of movements of one or more parts of the vehicle with respect to a vehicle-fixed reference system such as a vehicle body or a frame.

[0016] The autonomous control of the vehicle is performed based on a pre-reproduced manually controlled operation sequence. In this case, the vehicle autonomously executes the reproduced operation sequence. The vehicle is autonomously controlled to execute the reproduced operation sequence. This means that the autonomously controlled operation sequence is matched with the manually controlled operation sequence.

[0017] However, it is also possible to assume that the control of the vehicle is not autonomous but automated. That is, the vehicle executes a pre-reproduced manually controlled operation sequence, but is under the supervision of an operator at that time. In particular, the operator can handle (unexpected or unplanned) obstacles and dangerous situations. Thereby, the function can be realized particularly easily. This is because it is not necessary to provide additional sensors for detecting obstacles. Therefore, the automatic control of the vehicle can be regarded as an assisted driving function system or a driver assistance function system that uses sensor signals from already installed sensors.

[0018] In one embodiment, it is assumed that a warning is issued when the deviation between the current value and the target value for autonomous control exceeds the allowable range. In this regard, an unexpected slip value in the wheel or block wheel is assumed as an example. By issuing a warning, the operator can take corrective measures when a deviation exceeding the allowable range occurs, or terminate the autonomous control and shift to manual control. Also, if appropriately configured, when a deviation exceeding the allowable range is detected, the automatic control of the vehicle can be terminated autonomously rather than by the operator. An unacceptable deviation is a deviation exceeding the allowable value. The allowable value may be zero. In this case, even a slight deviation is not allowed.

[0019] The starting position of the vehicle in the manually controlled operation sequence preferably coincides with the starting position of the vehicle in the autonomously controlled operation sequence. That is, before executing an autonomous operation sequence, the vehicle moves to the position it occupied at the start of the manually controlled operation sequence.

[0020] According to a further embodiment, the vehicle executes an autonomously controlled operation sequence from the starting position of the reproduced operation sequence. Thereby, the autonomous control of the vehicle is performed to match the previously defined manual control.

[0021] In one embodiment, it is conceivable that the autonomously controlled operation sequence also includes the operation of a lifting device or a hydraulic actuator. In this case, not only the distance from the starting position to the ending position but also the movement and operation of the hydraulic actuator are acquired. In particular, it is suitable for an industrial truck to move goods from one place to another. An industrial truck typically has a lifting device that operates hydraulically or in another manner, and can load and unload goods with that lifting device. An industrial truck typically has a lifting mast with forks attached for loading pallets, containers, or other small goods / containers. Thereby, it can load at one place, move to another place, and unload there.

[0022] In an alternative and preferred embodiment, after the vehicle reproduces an operation sequence manually controlled based on the stored sensor data, the vehicle executes the operation sequence in the reverse direction. That is, the vehicle is autonomously controlled to execute the manually controlled operation sequence in the reverse direction. This means that the manually controlled operation sequences are executed in the opposite order under the opposite premises respectively. Thereby, the execution of each individual operation is performed at the same speed in the reverse direction.

[0023] In this embodiment, the reverse movement of the vehicle is performed autonomously. While the vehicle is moving backward, it moves in the reverse direction along the previously manually traveled trajectory. This is advantageous because it reduces the driver's burden and the risk of the vehicle colliding with obstacles.

[0024] Regarding the operation of the lifting device, when the reverse operation sequence is executed, the control can be extended to include an adjustment function. With this adjustment function, the hydraulic actuator or the lifting device does not operate completely opposite to the previous operation sequence. Rather, after unloading, the hydraulic actuator or the lifting device initially maintains the last state. For example, the fork can be withdrawn from the pallet when the reverse operation sequence is executed. Without considering this adjustment function, after the lifting device is lowered to unload, the lifting device will rise again and reloading will be performed again.

[0025] Alternatively or additionally, the adjustment function can be configured to determine whether the fork is still located within or below the cargo based on the acquired distance. When it is confirmed that the travel distance during reverse travel is greater compared to the length of the fork, the hydraulic actuator or the lifting device operates in the reverse operation sequence described above. In this case, it is conceivable that the execution of the reverse operation sequence for the hydraulic actuator or the lifting device is performed faster than the execution of the reverse operation sequence for the travel of the industrial truck. Thereby, the offset of the operation of the lifting device or the hydraulic actuator caused by the adjustment function can be compensated. Also, after the adjustment function is completed, it is also conceivable to interrupt, temporarily stop, or decelerate the execution of the reverse operation sequence for travel until the offset due to the adjustment function is compensated. In other words, this ensures that the offset between the travel parameter and the hydraulic operation parameter is minimized to an acceptable level or completely eliminated.

[0026] Similarly, after loading, an adjustment function that also offsets the operation of the hydraulic actuator or the lifting device is conceivable. Thereby, when the reverse operation sequence is executed, it is avoided that the loaded cargo is unloaded again. The offset can be considered as a variable or constant parameter.

[0027] Instead of the automatic operation of the adjustment function based on distance evaluation, the adjustment function may be manually operated, such as by the operator actuating a corresponding input element / switch.

[0028] Furthermore, the execution of a hybrid function is conceivable. This means that while the autonomous reverse travel is performed by the vehicle or appropriate control, the operation of the hydraulic actuator or the lifting device is performed by the operator.

[0029] Goods are often loaded and unloaded in storage areas with limited space. Examples include high-bay warehouses with narrow spaces. Therefore, when loading and unloading goods, a great deal of attention from the operator who operates the hydraulic actuator or lifting device is required. Accordingly, it is also conceivable to initially execute the reverse operation sequence at a lower speed. This can be instructed either by automatic control or by the operator. After the goods are taken out from the relevant storage location, the execution speed of the reverse operation sequence can be increased.

[0030] In one embodiment, the operator can always abort or invalidate the execution of the reverse operation sequence by operating the accelerator pedal, brake pedal, hydraulic actuator or lifting device, and / or the steering.

[0031] Furthermore, a limiting function can be added to the accelerator pedal or brake pedal, so that the reverse operation sequence is executed at different speeds according to the operating state. In an alternative embodiment that can be envisioned, the reduction in the execution speed of the reverse operation sequence can be continuously adjusted in the range of 0% to 100% via another input element.

[0032] Similarly, the reverse operation sequence can be executed at a speed exceeding 100% to accelerate the function. This function can also be temporarily assigned to the accelerator pedal or brake pedal instead of using another input element.

[0033] In a preferred embodiment, the vehicle position after reversing corresponds to the above-described vehicle position at the start of the manually controlled operation sequence. This means that the vehicle position at the start of the autonomously controlled operation sequence corresponds to the above-described end position of the manually controlled operation sequence.

[0034] According to one embodiment, the manually controlled operation sequence and the autonomously controlled operation sequence coincide on the contrary premise.

[0035] The computer program according to the present invention is used to execute the method or preferred embodiment according to the present invention. The computer program according to the present invention is designed to cause the data processing apparatus to implement the method or preferred configuration according to the present invention when executed on the data processing apparatus.

[0036] The data processing apparatus according to the present invention is adapted to implement the method or preferred embodiment according to the present invention. For example, a data processing apparatus including the computer program according to the present invention is thus adapted. This is particularly applicable when the computer program is loaded into the working memory of the data processing apparatus for execution.

[0037] Preferred embodiments of the present invention are shown in the drawings. The same reference numerals denote the same or functionally identical objects.

Brief Description of the Drawings

[0038]

Figure 1

Figure 2

Modes for Carrying Out the Invention

[0039] The forklift 101 shown in FIG. 1 travels along the track 103. The track 103 connects the starting point 105 to the ending point 107. That is, the forklift 101 departs from the starting point 105 and travels along the track 103 to the ending point 107.

[0040] The track 103 is selected such that the forklift 101 passes between the obstacles 109. In this case, the forklift 101 advances in the first traveling direction 111.

[0041] While the forklift 101 travels along the track 103, the sensor data of the forklift 101 is recorded and stored. When the forklift 101 reaches the end point 107, the forklift 101 turns back.

[0042] As shown in Figure 2, the forklift 101 reverses in the second traveling direction 201 along the same track 103. In this case, the forklift uses the sensor data collected during forward travel to confirm its orientation. The forklift compares this sensor data with the corresponding sensor data obtained during reverse travel. The forklift 101 determines the track 103 during reverse travel so that the sensor data quantitatively matches.

Explanation of Signs

[0043] 101 Forklift 103 Track 105 Starting point 107 End point 109 Obstacle 111 First traveling direction 201 Second traveling direction

Claims

1. A method for controlling a vehicle (101), in a method of manually controlling the vehicle (101) while storing sensor data from at least one sensor in the vehicle (101), acquire sensor data from the at least one sensor and compare it with the stored sensor data, while autonomously controlling the vehicle (101), reproduce the operation sequence of the vehicle (101) based on the stored sensor data, the operation sequence including the operation of a hydraulic actuator or a lifting device in addition to passing through a track, and a adjustment function is provided to offset the operation of the hydraulic actuator or the lifting device, when the vehicle (101) moves backward from the end point to the start point, compare the sensor data stored during forward movement with the sensor data acquired during backward movement, and determine the track so that the two sensor data match quantitatively during backward movement, thereby executing the operation sequence in the reverse direction. A method characterized by that.

2. The control method according to claim 1, characterized in that the vehicle (101) is autonomously controlled so that the acquired sensor data matches the stored sensor data.

3. The control method according to claim 1 or 2, characterized in that at least one operation amount in the vehicle or a part of the vehicle (101) is acquired and stored as sensor data.

4. The control method according to any one of claims 1 to 3, characterized in that the operation sequence of the vehicle (101) is reproduced based on the stored sensor data, and the vehicle (101) autonomously executes the operation sequence.

5. The control method according to any one of claims 1 to 4, characterized in that the vehicle (101) executes the operation sequence from the end position (107) of the reproduced operation sequence.

6. A computer program for implementing the method according to any one of claims 1 to 5.

7. A data processing device adapted to implement the method according to any one of claims 1 to 5.

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