Detection of Unsecured Load in Automatically Drivable Vehicles

Abstract

Disclosed is a method for detecting an unsecured load in an especially automatically drivable vehicle by means of a controller, wherein measurement data in the form of lateral accelerations and/or linear accelerations of the vehicle acquired by at least one acceleration sensor are received, a time interval for detecting the unsecured load is started when the measured lateral accelerations or linear accelerations exceed a threshold value, during the time interval started measurement data acquired by at least one sensor are received and derivatives with respect of time of the received measurement data are calculated, an event is counted when the derivatives with respect of time of the measurement data exceed the one threshold value, and the presence of an unsecured load is detected when a minimum number of counted events is reached that are counted during the started time interval.

Claims

1. A method for detecting an unsecured load in a vehicle that can be operated in an automated manner, using a controller, the method comprising: receiving measurement data including at least one of lateral accelerations and longitudinal accelerations of the vehicle acquired by at least one acceleration sensor; starting a time interval in response to a threshold value being exceeded by one of the lateral accelerations and longitudinal accelerations; during the time interval, receiving measurement data acquired by at least one sensor and calculating derivatives with respect to time of the received measurement data; counting an event in response to the derivatives with respect to time of the received measurement data exceeding the threshold value; and detecting the unsecured load in the vehicle in response to a minimum number of events being counted during the time interval.

2. The method according to claim 1, wherein the time interval one of (i) has a start time with a time offset of t.sub.0=√{square root over (b.sub.ia.sub.y)} and an end time of t.sub.end=√{square root over (3b.sub.ia.sub.y)} when the threshold value is exceeded by the lateral acceleration, and (ii) has a start time with a time offset of t.sub.0=√{square root over (l.sub.ia.sub.x)} and an end time of t.sub.end=√{square root over (3l.sub.ia.sub.x)} when the threshold value is exceeded by the longitudinal acceleration, where l is a length of a cargo space and b is a width of the cargo space of the vehicle.

3. The method according to claim 1, the calculating further comprising: calculating the derivatives with respect to time of the measurement data using at least one differentiator.

4. The method according to claim 1, the receiving measurement data further comprising: receiving, during the time interval, the measurement data from at least one of the at least one acceleration sensor, a sound sensor, a microphone, and a travel sensor.

5. The method according to claim 1, further comprising: in response to the minimum number of events being counted during the time interval, generating control commands configured to output a warning message.

6. The method according to claim 1 further comprising: in response to the minimum number of events being counted during the time interval, at least one of (i) bringing the vehicle to a safe state and (ii) reducing vehicle dynamics.

7. A controller for detecting an unsecured load in a vehicle that can be operated in an automated manner, the controller being configured to: receive measurement data including at least one of lateral accelerations and longitudinal accelerations of the vehicle acquired by at least one acceleration sensor; start a time interval in response to a threshold value being exceeded by one of the lateral accelerations and longitudinal accelerations; during the time interval, receive measurement data acquired by at least one sensor and calculate derivatives with respect to time of the received measurement data; count an event in response to the derivatives with respect to time of the received measurement data exceeding the threshold value; and detect the unsecured load in the vehicle in response to a minimum number of events being counted during the time interval.

8. A non-transitory machine-readable storage medium that stores a computer program for detecting an unsecured load in a vehicle that can be operated in an automated manner, the computer program comprising commands that, when executed by one of a computer and a controller, cause the one of the computer and the controller to: receive measurement data including at least one of lateral accelerations and longitudinal accelerations of the vehicle acquired by at least one acceleration sensor; start a time interval in response to a threshold value being exceeded by one of the lateral accelerations and longitudinal accelerations; during the time interval, receive measurement data acquired by at least one sensor and calculate derivatives with respect to time of the received measurement data; count an event in response to the derivatives with respect to time of the received measurement data exceeding the threshold value; and detect the unsecured load in the vehicle in response to a minimum number of events being counted during the time interval.

9. The controller according to claim 7, wherein the controller executes a computer program stored on a non-transitory machine-readable storage medium.

10. The method according to claim 4, wherein the travel sensor is a travel sensor of a wheel suspension of the vehicle.

Description

[0031] Preferred exemplary embodiments of the invention are explained in more detail below with reference to highly simplified schematic representations. In the drawings:

[0032] FIG. 1 shows a plan view of a vehicle having a cargo space for illustrating a method according to one embodiment, and

[0033] FIG. 2 shows a schematic flowchart for illustrating the method according to one embodiment.

[0034] FIG. 1 shows a plan view of a vehicle 1 with a cargo space 2 for illustrating a method 4 according to one embodiment. The method 4 is explained in more detail in FIG. 2.

[0035] The vehicle 1 has a controller 6 which can receive and evaluate measurement data from different sensors 8, 10, 12. For example, the vehicle 1 can have an acceleration sensor 8, which can use measurement data for an initial load securing check. The acceleration sensor 8 can be arranged, for example, in the chassis of the vehicle 1.

[0036] In the cargo space of the vehicle 1, a transport item or a load 14 is located for example. In the exemplary embodiment shown, the cargo space 2 is designed in the form of a rear seat bench or trunk of the vehicle 1. According to the BASt standard, the vehicle 1 can be designed as a fully automated vehicle and thus operated without a driver.

[0037] A further sensor 10 can be designed, for example, as a microphone or interior microphone. Furthermore, measurement data from sensors 12 configured as travel sensors can be received by the controller 6.

[0038] The controller 6 can furthermore establish a communication connection 16 with a teleoperator 18.

[0039] In the exemplary embodiment shown, the communication connection 16 can be designed in the form of an LTE or WLAN connection. In particular, the communication connection 16 can be used to receive instructions or to transmit warning messages.

[0040] FIG. 2 shows a schematic flowchart for illustrating the method 4 according to one embodiment. The method 4 is used to detect an unsecured load 14 in a vehicle 1 and can preferably be carried out by a controller 6.

[0041] The method 4 can substantially be divided into several stages. In a first stage, a time interval in which events are counted is opened.

[0042] Based on the counted events collected during a second stage, an unsecured or loose load 14 can be detected.

[0043] The third stage of the method 4 is designed to generate a response to a determined unsecured load 14. A response can be realized, for example, in the form of a warning message and/or by bringing the vehicle 1 to a safe state.

[0044] In a first step 20, measurement data in the form of lateral accelerations ay and/or longitudinal accelerations ax acquired by at least one acceleration sensor 8 are received.

[0045] The acquired measurement data are compared with a predefined threshold value by a threshold value detection 22. The threshold value can be defined in advance as part of a calibration.

[0046] If a threshold value is exceeded by the measured lateral accelerations a.sub.y and/or longitudinal accelerations a.sub.x, a time interval 24 for detecting the unsecured load 14 is started within the scope of an event counting period.

[0047] The threshold value can be exceeded, for example, if the unsecured load 14 is pushed against the cargo space 2 of the vehicle 1. The time interval 24 can have an immediate start time or a delayed start time t.sub.0. Accordingly, the time interval 24 can have an adjusted end time tend.

[0048] The start time t.sub.0 and the end time t.sub.end can be calculated according to the following formulas:

t.sub.0=√{square root over (b.sub.ia.sub.y)} and t.sub.end=√{square root over (3b.sub.ia.sub.y)}

if the lateral acceleration ay has exceeded the threshold value.

t.sub.0=√{square root over (l.sub.ia.sub.x)} and t.sub.end=√{square root over (3l.sub.ia.sub.x)}

if the longitudinal acceleration a.sub.x has exceeded the threshold value. In this case, b.sub.i equals a width of the cargo space 2, and l.sub.i equals a length of the cargo space 2.

[0049] For example, in the middle of the event counting window or of the time interval 24, the point in time at which a loose object or the load 14 in the case of an applied lateral acceleration a.sub.y can shift from a left to a right interior side of the cargo space 2 and hit the wall there.

[0050] During the started time interval 24, measurement data acquired by at least one sensor 8, 10, 12 are received and temporal changes or time derivatives 26, 28, 30 of the received measurement data are calculated. This can be implemented by a plurality of differentiator amplifiers 26, 28, 30, which are integrated, for example, into the controller 6.

[0051] Each sensor 8, 10, 12 can have a separate differentiator amplifier 26, 28, 30, which transforms the corresponding measurement data into derivatives with respect to time of the measurement data.

[0052] Measurement data from a plurality of travel sensors 12 of the wheel suspension are evaluated. For example, each of the four wheel suspensions can have its own travel sensor 12. The respective path sensors 12 can acquire measurement data in the form of paths or routes d.sub.1, d.sub.2, d.sub.3, d.sub.4.

[0053] The at least one interior microphone 10 can acquire measurement data in the form of sound signals which are converted to sound pressure levels L.sub.p by means of a sound pressure level calculation 32.

[0054] The respective temporal measurement data are then temporally derived 26, 28, 30 during the active time interval 24. As a result of the derivative 26 of the lateral accelerations a.sub.y and/or longitudinal accelerations a.sub.x with respect to time, a jerk j.sub.y is produced in the lateral direction and/or a jerk j.sub.x is produced in the longitudinal direction.

[0055] Subsequently, the derivatives with respect to time of the measurement data are subjected to a threshold value detection 34, 36, 38. If the derivatives with respect to time of the received measurement data exceed a threshold value, an event is counted.

[0056] The counting of the events can take place using an event counter 40 which is active during the time interval 24.

[0057] An unsecured load is detected when a minimum number 42 of counted events is reached that are counted during the started time interval 24.

[0058] If an unsecured load is detected, a response 44 can be initiated by the controller 6. For this purpose, the controller 6 can generate control commands which generate a warning message or which can bring the vehicle 1 into a secure state.