Method and device for checking a screw connection at a vehicle, in particular a wheel nut

Abstract

An apparatus (6) for inspecting helical elements (8) at a vehicle (2), particularly wheel nuts (8) of a wheel (4), comprises: at least one camera (10) configured to capture at least one image of the vehicle (2) such that the helical element (8) to be inspected is included in the captured image; and an evaluation device (14). The evaluation device (14) is configured to: identify the helical element (8) to be inspected in at least one captured image; determine the orientation of the helical element (8) to be inspected in at least one captured image; compare the determined orientation of the helical element (8) to be inspected with a pre-given orientation of the helical element (8) to be inspected; and output an error report if the previously determined orientation of at least one of the helical elements (8) to be inspected deviates from the pre-given orientation of the corresponding helical element (8) by more than a pre-given tolerance.

Description

Technical Field

[0001] The present invention relates to a method and an apparatus for inspecting helical connections, particularly wheel nuts, in vehicles. Background Technology

[0002] In particular, regulations stipulate that before starting a trip, the wheel nuts at the vehicle's wheels must be checked to ensure they are securely in place.

[0003] For automated motor vehicles, from a legal perspective and from the perspective of the operator's own interests, daily start-up inspections and other condition monitoring should be maintained or even strengthened on a larger scale.

[0004] Vehicles may also have other externally visible spiral connections that must be inspected regularly.

[0005] To date, these inspections have been performed manually or optically by personnel, such as the vehicle's driver, who walks around the vehicle before the trip begins and inspects the helical connections / wheel nuts. Summary of the Invention

[0006] The purpose of this invention is to simplify and speed up the inspection of helical connections on vehicles, especially wheel nuts at the wheels of vehicles, and to improve the reliability of the inspection.

[0007] This invention includes a machine method for inspecting the orientation of helical elements, particularly wheel nuts, in a vehicle. The method according to the invention includes: capturing at least one image of the vehicle using a camera, such that the helical element to be inspected is included in the captured image; identifying the helical element to be inspected in the at least one captured image; determining the orientation of the helical element to be inspected in the at least one captured image; comparing the determined orientation of the helical element to be inspected with a pre-given orientation of the helical element to be inspected; and outputting an error report if the previously determined orientation of at least one of the helical elements to be inspected deviates from the pre-given orientation of the corresponding helical element by more than a pre-given tolerance.

[0008] The present invention also includes an apparatus for inspecting the orientation of helical elements, particularly wheel nuts, in a vehicle. The apparatus according to the invention includes: at least one camera and an evaluation device. The at least one camera is configured to capture at least one image of the vehicle such that the helical element to be inspected is included in the captured image. The evaluation device is configured to: identify the helical element to be inspected in the at least one captured image; determine the orientation of the helical element to be inspected in the at least one captured image; compare the determined orientation of the helical element to be inspected with a pre-given orientation of the helical element to be inspected; and output an error report if the previously determined orientation of at least one of the helical elements to be inspected deviates from the pre-given orientation of the corresponding helical element by more than a pre-given tolerance.

[0009] The method and apparatus according to the present invention enable rapid, reliable, and convenient inspection of helical connections on vehicles, particularly wheel nuts at the wheels. It also improves the reliability of the inspection by preventing human error, which can occur during manual inspection of helical connections.

[0010] The predetermined orientation of the helical element (compared to its current orientation) can be the result of a previous inspection. In particular, the predetermined orientation of the helical element can be the result of an initial reference measurement performed after the helical element has been placed in its ideal state, for example, immediately after the wheel has been installed on the vehicle.

[0011] In one embodiment, the method according to the invention is performed at a stationary vehicle.

[0012] In one implementation, the method according to the invention is performed while the vehicle to be inspected passes by at least one camera. This allows the method to be performed particularly quickly, for example, within seconds. In particular, it enables the method to be performed without delaying the departure of the vehicle.

[0013] In one embodiment, the device according to the invention includes at least two cameras. In this way, spiral elements, particularly wheel nuts, arranged on both sides of the vehicle can be inspected simultaneously as the vehicle passes between the at least two cameras in a single pass. This further accelerates the method.

[0014] In an alternative embodiment, two devices for inspecting spiral elements according to the invention can be used, each of which has a camera, and the devices are respectively placed on each of the two sides of the vehicle.

[0015] In one embodiment, determining the orientation of the helical element to be inspected includes: determining the relative orientation of at least two adjacent helical elements with respect to each other, and comparing it with a pre-given relative orientation of an adjacent helical element. Determining and comparing the orientations of adjacent helical elements allows for a particularly simple and reliable inspection of the orientation of the helical elements.

[0016] In one embodiment, an indicating element, such as a wheel nut indicator, is mounted on a screw element. In this case, determining the orientation of the screw element to be inspected includes determining the orientation of the indicating element mounted on the corresponding screw element. Because the indicating element is specifically designed for this purpose, the orientation of the indicating element can be identified and determined by machine in a particularly simple and reliable manner.

[0017] In one embodiment, the method further includes identifying the absence of a helical element in at least one captured image, and outputting an error report if at least one missing helical element is identified. By identifying missing helical elements, vehicle safety can be further improved using the method according to the invention.

[0018] In one embodiment, the method includes illuminating the spiral element to be inspected in order to improve the quality of at least one captured image. In one embodiment, the device according to the invention correspondingly has at least one illumination device configured to illuminate the spiral element to be inspected. The illumination device may include at least one LED.

[0019] The orientation of the spiral element can be identified particularly well and reliably by machine in images taken of a well-lit spiral element. In this way, the quality and reliability of the method according to the invention can be further improved.

[0020] In one embodiment, the method includes storing at least one captured image of the spiral element for recording purposes. For this purpose, the device according to the invention can be equipped with a storage device capable of storing the captured images and recalling them at a later time when needed.

[0021] By storing and machine-evaluating images taken at different times, it is possible to identify, particularly well, the gradual changes in the orientation of the spiral element.

[0022] As an alternative or additional option, the captured images can be stored outside the device according to the invention, for example, in a central server or virtual cloud.

[0023] In one embodiment, the device according to the invention is configured to output an error report to a higher-level instance, such as a central system, which further processes the information. The higher-level instance may, for example, be configured to inform the driver, vehicle driver, inspector, and / or other personnel of the identified error. The higher-level instance may also be configured to store information related to the performance of inspections and the inspection results in a fleet management system.

[0024] In one implementation, the device itself has an output device that enables the device to output an error report.

[0025] The output device can be integrated into the testing equipment or camera. Alternatively, the output device can be constructed separately from the testing equipment and / or camera.

[0026] The device can be equipped with an optical output device, such as a display and / or a signal light, which enables the device to output an optical error report.

[0027] As an alternative or additional option, the device can be equipped with acoustic output devices, such as speakers, buzzers, and / or horns. This enables the device to output acoustic error reports.

[0028] If no error is identified, an optical and / or acoustic confirmation (“OK message”) can be output to indicate that the vehicle’s spiral components have been inspected and are in normal condition. Attached Figure Description

[0029] Embodiments of the present invention will now be described with reference to the accompanying drawings. Wherein: Figure 1 A schematic top view shows a vehicle with a device according to the invention for inspecting a spiral element of the vehicle positioned thereon. Figure 2 A schematic side view of a device for inspecting a spiral element at a vehicle according to the present invention is shown; Figure 3 An example of an indicator element configured as a wheel nut indicator is shown, which can be mounted on a wheel nut; Figure 4 A wheel with multiple wheel nuts is shown, on which wheel nut indicators are mounted; Figure 5 Showing from Figure 4 A magnified view of the area shows two adjacent, correctly oriented wheel nuts. Figure 6 Showing from Figure 4 A magnified view of the area reveals two adjacent wheel nuts that are not correctly oriented. Detailed Implementation

[0030] Figure 1 The diagram illustrates a vehicle 2, particularly a motor vehicle 2 with four wheels 4. A device 6, according to the invention, for inspecting wheel nuts 8 (screw elements) of the wheel 4 is positioned at one of the wheels 4.

[0031] Vehicle 2 can be, for example, a passenger car, a truck, or a bus. Vehicle 2 can also be a trailer, not shown in the figure. Vehicle 2 can also be a rail transport vehicle or an aircraft.

[0032] Figure 2 The schematic diagram shows a device 6 according to the invention for inspecting a spiral element 8, in particular a wheel nut 8, together with a wheel 4, the wheel nut 8 of which is to be inspected.

[0033] Device 6 includes at least one image capturing device, or camera 10. Camera 10 is set up and configured to capture at least one image of wheel 4, such that the wheel nut 8 of wheel 4 to be inspected is included in the image captured by camera 10.

[0034] like Figure 2 As exemplarily shown, at least one camera 10 can be mounted on a bracket or support 12. Alternatively, the camera 10 can also be mounted on the ceiling or wall of a room in a measurement site or garage (not shown). Alternatively, the camera 10 can also be a mobile user terminal, such as a smartphone camera 10.

[0035] Optionally, the device 6 may additionally include an illumination device 15, which is configured and constructed to illuminate the wheel 4 having the wheel nut 8 to be inspected.

[0036] The device 6 also includes an evaluation device 14, which is set up and constructed to identify the wheel nut 8 to be inspected in at least one captured image and to determine the orientation of the wheel nut 8 to be inspected in at least one captured image.

[0037] This can be done using known methods of automatic image recognition and / or artificial intelligence methods.

[0038] The testing device 14 is further configured to compare the determined orientation of the wheel nut 8 to be inspected with the predetermined orientation of the wheel nut 8 to be inspected, and to output an error report if the previously determined orientation of the wheel nut 8 to be inspected deviates from the predetermined orientation by more than a predetermined tolerance.

[0039] This can also be done using known methods of automatic image recognition and / or artificial intelligence methods.

[0040] The testing device 14 may be configured to output an error report to a central system 16, which further processes the error report. The central system 16 may be configured to inform the driver of the motor vehicle 2, or the vehicle driver, inspector, and / or other responsible personnel of the error identified.

[0041] The device 6 and / or central system 16 according to the present invention can be equipped with storage devices 24 and 26 respectively, in which the captured images can be stored and recalled at a later time when needed.

[0042] Error reports can be transmitted to the central system 16 via wired or wireless means, such as via WLAN or Bluetooth data connection.

[0043] The testing equipment 14 and the central system 16 are each equipped with corresponding transmitting and receiving devices 17.

[0044] As an alternative or additional option, an output device 18 can be provided in the device 6 according to the invention itself, which is configured and constructed to output error reports.

[0045] The output device 18 can be integrated into the testing device 14 or the camera 10. Alternatively, the output device 18 can be constructed separately from the testing device 14 and / or the camera 10.

[0046] The output device 18 may include an optical output device 18a, such as a display and / or a signal light, which is configured and constructed to output an optical error report.

[0047] As an alternative or additional option, output device 18 may include acoustic output device 18b, such as a speaker, buzzer and / or horn, wherein acoustic output device 18b is configured and constructed to output acoustic error reports, such as warning tones and / or acoustic prompts.

[0048] In one embodiment of the invention, the indicator element 20, also known as a wheel nut indicator, can be mounted on the wheel nut 8.

[0049] Figure 3 An example of a wheel nut indicator 20 is shown, which can be mounted on a wheel nut 8. The wheel nut indicator 20 has a protrusion 22 in particular, which facilitates determining the spatial orientation of the wheel nut indicator 20, and thus also facilitates determining the orientation of the wheel nut 8 on which the wheel nut indicator 20 is mounted.

[0050] Indicator element / wheel nut indicator 20 in Figure 3The structural form shown is merely exemplary. Other structural forms of the indicator element / wheel nut indicator 20 can also be used.

[0051] Figure 4 An exemplary illustration shows a wheel 4 of a motor vehicle 2, which has a plurality of wheel nuts 8 on which are mounted objects such as... Figure 3 The indicator element / wheel nut indicator 20 shown is shown.

[0052] Figure 5 and Figure 6 The following are respectively shown from Figure 4 The magnified part shows two adjacent wheel nuts 8, on which indicator elements 20 are installed respectively.

[0053] exist Figure 5 In the center, the protrusions 22 of the two indicator elements 20 are oriented along a common line, so that they point towards each other. This indicates that the two wheel nuts 8 are correctly oriented and fully tightened.

[0054] exist Figure 6 In this case, the protrusions 22 of the two indicator elements 20 are not oriented relative to each other along a common line. Specifically, the wheel nut 8 shown on the left is relative to... Figure 5 The orientation shown is rotated counterclockwise by approximately 45°. The indicator element 20 shown on the left, and therefore the wheel nut 8 on the left where the indicator element 20 is mounted, no longer has the pre-defined orientation. This indicates that the wheel nut 8 on the left has loosened.

[0055] If the testing equipment 14 identifies the wheel nut 8 or the indicator element 20, such as... Figure 6 If the orientation shown in the example is incorrect, the testing device 14 will output an error report indicating that at least one wheel nut 8 at the wheel 4 being inspected is not in the set position, but may have been loose.

[0056] Indicator element 20 in Figure 5 and Figure 6 The orientation shown can be identified particularly well using automatic image recognition methods. Therefore, it is particularly reliable to identify whether the indicator element 20 and, consequently, the wheel nut 8 on which the indicator element 20 is mounted, are in the set orientation.

[0057] However, as an alternative, the orientation of the wheel nut 8 can also be identified based on the geometry of the wheel nut 8, which is typically constructed as a hexagonal nut and does not have an indicator element 20 installed on it.

[0058] If there is no indicator element 20 on the wheel nut 8, it is possible that the wheel nut 8 may have accidentally rotated around its own axis to such an extent between two inspections that the wheel nut, although loosened, cannot be visually identified due to the symmetry of the wheel nut 8, since the current orientation of the wheel nut coincides with the previous reference image.

[0059] While statistically possible, it is extremely unlikely that the wheel nut 8 will gradually loosen, provided that the method according to the invention is performed periodically. Therefore, in this case, it can also be considered that the wheel nut 8 can be reliably identified before it is completely loosened.

[0060] The lower the rotational symmetry of the wheel nut 8, or the helical element 8, the more reliable the identification according to the present invention.

Claims

1. A method for machine inspection of a helical element (8), particularly a wheel nut (8), at a vehicle (2), wherein, The method includes: At least one image of the vehicle (2) is captured using a camera (10) such that the spiral element (8) to be inspected is included in the captured image; The machine identifies the spiral element (8) to be inspected in at least one captured image; In the at least one captured image, the machine determines the orientation of the spiral element (8) to be inspected; The determined orientation of the helical element (8) to be inspected is compared with the pre-given orientation machine of the helical element (8) to be inspected; Furthermore, if the previously determined orientation of at least one of the spiral elements (8) to be inspected deviates from the pre-given orientation of the corresponding spiral element (8) by more than a pre-given tolerance, an error report is output.

2. The method according to claim 1, wherein, The machine determination of the orientation of the helical element (8) to be inspected includes: determining the relative orientation of adjacent helical elements (8) relative to each other, and comparing it with a pre-given relative orientation of adjacent helical elements (8).

3. The method according to any one of the preceding claims, wherein, The indicator element (20) is mounted on the spiral element (8), and the machine determination of the orientation of the spiral element (8) to be inspected includes: the machine determining the orientation of the indicator element (20) mounted on the corresponding spiral element (8).

4. The method according to any one of the preceding claims, wherein, The method includes capturing at least one image of the vehicle (2) while the vehicle (2) passes by at least one camera (10).

5. The method according to any one of the preceding claims, wherein, The method includes the machine identifying the absence of a spiral element (8) and outputting an error report if at least one spiral element (8) is identified as missing.

6. The method according to any one of the preceding claims, wherein, The method includes illuminating the spiral element (8) to be inspected.

7. The method according to any one of the preceding claims, wherein, The method includes storing the at least one captured image for recording purposes.

8. A device (6) for inspecting spiral elements (8), particularly wheel nuts (8), at a vehicle (2), wherein, The device includes: At least one camera (10) configured and constructed to capture at least one image of the vehicle (2) such that the spiral element (8) to be inspected is included in the captured image; and Testing equipment (14), which is set up and constructed for, Identify the spiral element to be inspected (8) in the at least one captured image; The orientation of the spiral element (8) to be inspected is determined in at least one captured image; The determined orientation of the helical element (8) to be inspected is compared with the predetermined orientation of the helical element (8) to be inspected; and If the previously determined orientation of at least one of the spiral elements (8) to be inspected deviates from the pre-given orientation of the corresponding spiral element (8) by more than a pre-given tolerance, an error report is output.

9. The device according to claim 8, comprising: Optical output device (18a), which is configured and constructed for outputting optical error reports; and / or An acoustic output device (18b) is configured and constructed to output acoustic error reports.

10. The device according to claim 8 or 9, wherein, The testing device (14) is set up and constructed to determine the relative orientation of adjacent spiral elements (8) relative to each other and to compare them with a pre-given relative orientation.

11. The device according to any one of claims 8 to 10, wherein, The testing device (14) is configured to identify the indicator element (20) mounted on the spiral element (8) and determine the orientation of the indicator element (20) mounted on the spiral element (8).

12. The device according to any one of claims 8 to 11, wherein, The device includes a lighting device (15) which is configured and constructed to illuminate the spiral element (8).

13. The device according to any one of claims 8 to 12, wherein, The at least one camera (10) is set up and configured to capture at least one image of the vehicle (2) while the vehicle (2) is passing by the at least one camera (10).

14. The device according to any one of claims 8 to 13, wherein, The testing device (14) is set up and constructed to identify the absence of a spiral element (8) and to output an error report if at least one spiral element (8) is identified as missing.

15. The device according to any one of claims 8 to 14, wherein, The device includes a storage device (24) configured and constructed for storing the at least one captured image.

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