Method for calibrating a tachograph device for use in a vehicle and calibration device

Abstract

The invention relates to a method for calibrating a tachograph device (10) for use in a vehicle (11), comprising the following steps, which are carried out by a calibration device (12): receiving pulse signals (29) from a pulse sensor (23) of a speedometer (22) of the vehicle (11); receiving distance data (16) from a laser measuring device (13) describing distances between the laser measuring device (13) and a predefined reference point of the vehicle (11); receiving tire measuring device data from a tire measuring device (17) describing a rotation of the wheel (18) and a circumference of the wheel (18) of the tire; calculating, on the basis of the distance data (16), a traveled distance; calculating, on the basis of the wheel circumference and the rotation of the wheel (18), a circumferential distance of the wheel (18);Calculating, on the basis of the travelled distance and a number of pulse signals (29), a tachograph constant for the tachograph device (10) which describes a relationship between a number of pulses and a distance travelled by the vehicle (11);

Description

[0001] The invention relates to a method for calibrating a tachograph device for use in a vehicle and a calibration device for calibrating a tachograph device for use in a vehicle.

[0002] According to current Brazilian law, all transport vehicles with a gross vehicle weight exceeding 4.536 tons, vehicles transporting dangerous goods, vehicles transporting students, and vehicles carrying more than ten passengers must have a calibrated tachograph installed. Calibration must be performed every two years by an authorized workshop. There are two calibration procedures: the roll test, which is applicable to most standard vehicles, and the short-distance test, which is used as an exception for special vehicles where the roll test cannot be performed. These vehicles include special vehicles such as cranes, construction vehicles, trolleybuses, and oversized / overweight vehicles that are not suitable for the roll test.The roller test is carried out using equipment installed on a floor where the drive wheels can run over the moving rollers and simulate driving on the road.

[0003] Roller testing requires significant investment in equipment, infrastructure, and regular maintenance. Short-distance testing is currently a manual process, involving driving the vehicle on a 20-meter track with distance markers on the ground. Later, the calibration calculations are also performed manually. This process is inaccurate and prone to errors and fraud. Furthermore, newer vehicles equipped with safety features, such as ESP (Electronic Stability Program), cannot be driven on roller testing equipment because this causes driver error and the wheels lose traction. Performing calibration on these vehicles would require disabling the ESP module, which would introduce further errors into other electronic modules and create safety issues if the process is performed incorrectly.

[0004] An example of a role check is described in the following document.

[0005] EP 0 837 332 A2 describes a device for determining the device constants in a control unit installed in a vehicle. A pulse generator arranged in the vehicle is connected to the control unit to record the distance traveled by the vehicle. The determination of the device constants, which are to be set in the control unit based on the vehicle's characteristics, is performed on a roller dynamometer. The roller dynamometer supplies a signal relating to the distance traveled to a measuring computer by detecting the roller speed and a wheel circumference signal by detecting the number of revolutions of a vehicle wheel driven by the roller dynamometer.

[0006] Examples of short-distance tests are provided in the following documents.

[0007] DE 10 2004 047 506 B4 describes a method and a device for image-based calibration of tachographs in vehicles. In this method, at least one marking arranged on a vehicle wheel is detected by an image sensor while the vehicle is moving. A rotational movement of the marking is analyzed using at least two consecutive image recordings, with the position of the marking in the respective image recordings being taken into account. The rotational movement is related to the distance traveled by the vehicle.

[0008] DE 10 2009 038 742 A1 describes a device for verifying parameters of a tachograph, comprising a tachograph, a measurement evaluation device, a sensor barrier, a sensor associated with the sensor barrier, and a path length measuring device. The path length measuring device is an electronic measuring device, preferably an optoelectronic measuring device. The path length measuring device is arranged on a vehicle.

[0009] DE 10 2007 019 367 A1 describes an image-based calibration of a tachograph. In this method, an image sensor detects an angle-coded marking on a vehicle wheel during vehicle movement, and a further device detects the distance traveled by the vehicle. The tachograph can then be calibrated based on an evaluation of the rotational movement of the marking.

[0010] It is an object of the present invention to provide a method for calibrating a tachograph device without using a chassis dynamometer, which provides a required accuracy and which is resistant to fraud.

[0011] This object is achieved by the subject matter of the independent claims. Advantageous developments with expedient and non-trivial further embodiments of the invention are precisely specified in the dependent claims, the following description, and the drawings.

[0012] The invention also includes embodiments that provide additional technical advantages.

[0013] The present invention relates to a method for calibrating a tachograph device for use in a vehicle. In other words, the method is intended to calibrate the digital tachograph device so that it is calibrated for use in the vehicle. The method comprises the following steps, which are performed by the calibration device. The calibration device can be configured as a user device, such as a smartphone or a handheld device.

[0014] A first step involves receiving pulse signals from a pulse sensor of a speedometer of the vehicle during a calibration movement period of the vehicle. In other words, to calibrate the tachograph device for the vehicle, the vehicle performs the calibration movement over the calibration movement period. During the calibration movement period, the speedometer's pulse sensor transmits the pulse signals. The calibration device receives the pulse signals and counts the number of pulse signals received during the calibration movement period.

[0015] During the vehicle's calibration movement, a laser measuring device determines distances between the laser measuring device and a predefined reference point on the vehicle. The laser measuring device sends distance data, which includes the determined distances between the laser measuring device and the predefined reference point on the vehicle, to the calibration device, and the calibration device receives the distance data.

[0016] The calibration device receives tire gauge data from a tire gauge for a wheel of the vehicle. The tire gauge data describes the wheel's rotation during the vehicle's movement and the tire's circumference. The diameter records the wheel's rotation during the calibration movement and transmits the recorded rotation to the calibration device. The tire gauge further determines the tire's circumference and transmits the tire's circumference to the calibration device.

[0017] The calibration device calculates the distance traveled by the vehicle during the calibration movement period based on the distance data. In other words, the calibration device uses the distances between the laser measuring device and the predefined reference point of the vehicle, measured during the calibration movement, to determine the distance traveled by the vehicle.

[0018] The calibration device calculates the wheel's orbital distance during the calibration movement period based on the wheel circumference and wheel rotation. In other words, the calibration device calculates the wheel's orbital distance based on the wheel circumference and wheel rotation recorded by the tire measuring device.

[0019] In the next step, the calibration device verifies the travel distance calculated based on the distance data provided by the laser measuring device with the orbital distance calculated based on the tire measuring device data provided by the tire measuring device. Successful verification of the travel distance may require a difference between the travel distance and the orbital distance that is below a predefined threshold.

[0020] If the verification condition is not met, the calibration device can terminate the calibration process. After successfully verifying the travel distance with the orbital distance, the calibration device calculates a tachograph constant for the tachograph device based on the travel distance and the number of pulse signals received during the calibration movement period. This constant describes a correlation between the number of pulses and the distance traveled by the vehicle. In other words, once the travel distance has been verified, the calibration device calculates the relationship between the distance traveled during the calibration movement period and the number of pulse signals received during the calibration movement period.

[0021] The invention has the advantage that the use of the laser measuring device allows for the automated determination of the route. Using the circular route allows the route to be checked for errors and fraud. Therefore, the method allows for reliable calibration of the tachograph device.

[0022] According to a further embodiment of the invention, the method comprises sending the calibration signal, which includes the tachograph constant, to the tachograph device. In other words, the tachograph constant calculated by the calibration device is delivered to the tachograph device via the calibration signal. This embodiment has the advantage that the calibration device is designed to calibrate the tachograph device.

[0023] According to a further embodiment of the present invention, the method comprises checking whether the traveled distance is above a predefined threshold distance. In other words, it is necessary for the vehicle to travel at least the predefined threshold distance during the calibration process. The calibration device checks whether the traveled distance traveled by the vehicle is above the predefined threshold distance. The calibration device can terminate the calibration process or can indicate that the traveled distance is below the predefined threshold distance. If the traveled distance is reached, the calibration device can continue with the calibration process.

[0024] According to a further embodiment of the present invention, the method comprises receiving camera data from a camera device by the calibration device. The camera data includes images and / or a video recorded by the camera device during the calibration movement period. In other words, the camera device is used during the calibration process. The camera device can be arranged in a predefined position to have a view of the vehicle during the calibration movement. Therefore, the movement of the vehicle is recorded by the camera device, and the video is delivered to the calibration device. This embodiment has the advantage that the calibration process is recorded. The recording allows for reliable documentation of the calibration process. An inspector can therefore use the camera data to check whether the calibration was performed correctly.

[0025] According to a further embodiment of the present invention, the method comprises detecting the movement of the vehicle in the camera data. In other words, the calibration device can track the movement of the vehicle in the media provided in camera data. The method comprises determining a detected route of the vehicle based on the tracked movement of the vehicle. In other words, the calibration device can monitor the movement of the vehicle to determine the detected route of the vehicle during calibration based on the camera data. Verifying the route comprises verifying the route with the detected route. In other words, the detected route determined by the calibration device based on the camera data is used to verify the route.Verification of the route may require that the route meets a predefined condition regarding the detected route.

[0026] According to a further embodiment of the present invention, the method comprises detecting the movement of the camera data by the calibration device. The method comprises the step of determining a route of the vehicle during the calibration movement based on the detected movement of the vehicle. In other words, the calibration device tracks the movement of the vehicle in the camera data. Based on the tracked movement, the calibration device determines the path of the vehicle during the calibration process. In a next step, the calibration device determines whether the route satisfies the predefined route condition. In other words, in order to proceed with the calibration method, it may be necessary for the route evaluated for the vehicle to satisfy the predefined route condition.The predefined route condition may require that the vehicle's route be straight or follow a specific path with respect to the laser device.

[0027] According to a further embodiment of the present invention, the method comprises sending a cloud signal to a server device by the calibration device. The cloud signal comprises the tachograph constant evaluated by the calibration device for the tachograph device and the data received by the calibration device. In other words, the calibration device delivers the distance data, the tire gauge data, and the camera data, as well as the calculated tachograph constant, to the server device via the cloud signal. This embodiment has the advantage that the calibration process can be verified by the server device. Therefore, it may be possible to detect errors or fraud during the calibration process by the server device.

[0028] According to a further embodiment of the present invention, the method comprises performing a user authorization process. In other words, to perform the calibration method, the calibration device may require the user to perform the predefined authorization process. The authorization process may comprise identifying and authorizing the user. The authorization process may comprise authorizing the user using a secure card.

[0029] According to a further embodiment of the present invention, the method comprises receiving an approval message from the server device by the calibration device. In other words, the calibration device provides the tachograph constant and the data received by the calibration device to the server device. The server device can analyze the data and the calculated tachograph constant. If the data and the tachograph constant are verified by the server device, the server device sends the approval message to the calibration device. The approval message can indicate that the calibration is accepted.If the server device fails to verify the tachograph constant, the server device may refuse to provide the authorization message and / or may provide an error message indicating that the tachograph constant verification has failed. The error message may include a request to repeat the calibration process.

[0030] A second aspect of the present invention relates to a calibration device. The calibration device is designed to receive pulse signals from a pulse sensor of a speedometer of the vehicle during a calibration movement period of the vehicle.

[0031] The calibration device is configured to receive distance data from a laser measuring device, wherein the distance data describes distances between the laser measuring device and a predefined reference point of the vehicle during the calibration movement period of the vehicle. The calibration device is configured to receive tire measuring device data of the vehicle. The diameter data describes a rotation of a wheel during the movement and a wheel circumference of the tire. The calibration device is configured to calculate a distance traveled by the vehicle during the calibration movement period based on the distance data. The calibration device is configured to calculate a rotational distance of the wheel during the calibration movement period based on the wheel circumference of the tire and the rotation of the wheel.The calibration device is designed to verify the traveled distance with the circulating distance. The calibration device is designed to calculate a tachograph constant for the tachograph device based on the traveled distance and a number of pulse signals received during the calibration movement period. This constant describes a relationship between a number of pulses and the distance traveled by the vehicle.

[0032] For use cases or application situations that may occur during the method and which are not explicitly described here, it may be provided that, in accordance with the method, an error message and / or a request for user feedback is output and / or a default setting and / or a predefined initial state is set.

[0033] The invention also includes combinations of the features of the described embodiments.

[0034] An exemplary implementation of the invention is described below. The figures show: Fig. 1 shows a schematic representation of the structure of the calibration procedure; Fig. Figure 2 shows another schematic representation of the setup of the calibration procedure; and Fig. Figure 3 shows a schematic representation of the process.

[0035] The embodiment explained below is a preferred embodiment of the invention. However, in the embodiment, the described components of the embodiment each represent individual features of the invention, which are to be considered independently of one another and each develop the invention independently of one another and are therefore also to be considered a component of the invention, either individually or in a combination other than that shown. Furthermore, the described embodiment can also be supplemented by other, already described features of the invention.

[0036] In the figures, elements that provide the same function are marked with identical reference numerals.

[0037] Fig. 1 shows a schematic representation of the structure of the calibration procedure.

[0038] The method can be used to determine the tachograph constant for a tachograph device 10 to be used in the vehicle 11. The tachograph constant can describe the relationship between a number of pulses and a distance traveled by the vehicle 11. Therefore, it may be necessary to determine a travel distance and the number of pulses while traveling along the travel route. To determine the tachograph constant, a calibration process can be performed, wherein the vehicle 11 travels at least a predefined distance. While the vehicle 11 is traveling, a number of pulse signals 29 are recorded. The calibration can be performed by a calibration device 12, which can be configured as a tablet, smartphone, or handheld device.

[0039] Since distance measurements are prone to fraud and error, a laser measuring device 13 is provided. The laser measuring device 13 can be configured to emit laser pulses 14 that can be reflected by a reflector device 15 attached to the vehicle 11. The laser measuring device 13 can be configured to record the laser pulses 14 reflected by the reflector device 15 and to determine respective distances between the laser device and the reflector device 15, which can be used as a predefined reference point of the vehicle 11. The laser measuring device 13 can send distance data 16 comprising the measured distances to the calibration device 12. The calibration device 12 can receive the distance data 16 and can determine the distance of the vehicle 11 during calibration based on the measured distances.

[0040] To provide a reliable travel distance, the travel distance can be compared with other distances. Therefore, during calibration, a tire gauge 17 can be attached to a wheel 18 of the vehicle 11. The tire gauge 17 can be configured to evaluate a wheel circumference of the wheel 18. The tire gauge 17 can further be configured to record a rotation of the wheel 18 during the movement of the vehicle 11. The tire gauge 17 can provide tire gauge data 19, including the rotations of the wheel 18 and the circumference of the wheel 18, to the calibration device 12. Based on the rotations and the circumference of the wheel 18, the calibration device 12 can determine a rotation distance of the wheel 18 during the calibration movement period. The calibration device 12 can use the rotation distance to verify the travel distance in a verification process.

[0041] To further verify the route, the calibration process setup may further include a camera device 20 configured to record images and / or a video of the vehicle 11 during the calibration movement and to provide camera data 21 to the calibration device 12. The calibration device 12 may identify and track the vehicle 11 in the images and / or videos and may calculate a video route describing the distance traveled by the vehicle 11 during the calibration process according to the camera data 21. The calibration device 12 may further determine a route of the vehicle 11 during the calibration process and check whether the route meets a predefined route condition.

[0042] The calibration device 12 can be configured to verify the driving route during the verification process. During the verification process, the calibration device 12 can compare the driving route with the circulating route and / or the video driving route. Successful verification can require that the driving route fulfill a predefined verification condition regarding the circulating route and the video driving route. The verification condition can include a difference between the driving route and the circulating route and / or the video driving route that is below a predefined threshold difference.

[0043] The vehicle 11 may include a speedometer 22 having a pulse sensor 23 configured to provide pulse signals 29 during the movement of the vehicle 11. The calibration device 12 may be configured to receive the pulse signals 29 from the pulse sensor 23 of the speedometer 22. The transmission of the pulse signals 29 from the pulse sensor 23 to the calibration device 12 may be via a workshop connection device 24.

[0044] The calibration device 12 may be configured to use the number of pulse signals 29 received during the movement of the vehicle 11 and the distance traveled by the vehicle 11 to calculate a tachograph constant for the tachograph device 10 for the vehicle 11, which constant describes a relationship between the pulse signals 29 and the distance traveled. Calculating the constant of the speedometer 22 may require successful verification of the distance traveled.

[0045] If the verification condition is not met, the calibration device 12 may reject the calculation of the tachograph constant and request that the distance measurement be repeated.

[0046] The calibration device 12 can be configured to send a cloud signal 25 to an external server device 26. The cloud signal 25 can include the tachograph constant calculated by the calibration device 12 and the data received by the calibration device 12. The server device 26 can store the data. The server device 26 can further be configured to verify the tachograph constant calculated by the calibration device 12. Therefore, the server device 26 can recalculate the routes and / or check the video and / or images for a valid execution of the calibration process.

[0047] If the verification of the tachograph constant is successful, the server device 26 can send an approval message 27 to the calibration device 12. Otherwise, the server device 26 can send a message requesting a repeat calibration to the calibration device 12. The calibration device 12 can be configured to receive the approval message 27. The calibration device 12 can be configured to send a calibration message 28 comprising the tachograph constant to the tachograph device 10 after calculating the tachograph constant or after receiving the approval message 27 from the server device 26.

[0048] Fig. Figure 2 shows another schematic representation of the setup of the calibration procedure.

[0049] The main objective of the setup is to improve the short-distance testing option so that it can be safely applied to all vehicles 11, i.e. standard and special vehicles, old and new vehicles, while avoiding the high investment in conventional roller testing, improving the accuracy of the test, avoiding the need to turn off the ESP module, and greatly minimizing the risk of manual errors and fraud in the calibration process.

[0050] A new set of measuring devices is proposed to replace the manual process currently used in short-distance testing. A core of the setup may be a calibration device 12, which may be a rugged portable computer, such as a tablet, running calibration software with an intuitive and easy-to-use application. With this software, a workshop operator can follow a standard procedure, recording all test data electronically. The calibration device 12 may be connected to external accessories that may form a test setup. A workshop connection device 24 may be a wireless device connected to a front-panel connector of the tachograph device 10 of the vehicle 11.It may be configured to send and receive data, including speed pulse signals 29, from / to the tachograph device 10 to / from the calibration device 12 during the test. A laser measuring device 13 may be equipped with a wireless interface. The laser device can automatically measure the distance traveled by the vehicle 11 during the test, enabling high accuracy and replacing manual measurement by markings on the ground. A tire measuring device 17 may be a wireless device attached to a drive wheel 18 of the vehicle 11. The tire measuring device 17 can measure a number of rotations of the wheel 18, including a partial rotation, and can calculate a circumference of the wheel 18. It can operate as redundant information to perform a cross-check on the calibration results and register the actual size status of the wheel 18.

[0051] Device functions during the calibration process: The workshop connection device 24 can be installed in the tachograph device 10 inside a cabin of the vehicle 11. The workshop connection device 24 can read the number of pulse signals 29 generated by the pulse sensor 23 connected to the tachograph and send them to the calibration device 12 via the wireless interface. The tire measuring device 17 can be installed in a drive wheel 18, mounted at any position / angle on its side. The tire measuring device 17 can measure a number of rotations of the wheel 18, even if it is a partial rotation, and send them to the calibration device 12 via the wireless interface. The laser measuring device 13 can be installed at one end of a test track, in front of the vehicle 11, and point at a white reflector installed in front of the vehicle 11.The laser measuring device 13 can measure the distance to the reflector and send it to the calibration device 12 via the wireless interface. The laser measuring device 13 can measure the distance before the vehicle 11 begins moving (initial distance), can continue measuring while the vehicle 11 is moving (intermediate distance), and can measure at the end of the test when the vehicle 11 is stopped (final distance). The calibration device 12 can calculate the distance traveled by the vehicle 11 as follows: Final Distance - Initial Distance. Meanwhile, an intermediate distance can be used to confirm whether the vehicle 11 has already traveled the defined minimum distance for the test, which can be between 15 m and 20 m. To increase the robustness of this operation, an operator must be identified and authorized in the system before starting the calibration process.This authorization function can also run on the calibration device 12. When the vehicle 11 is stopped, the calibration device 12 can extract all information from the sensors, including the distance traveled, the rotations of the wheel 18, and the number of pulse signals 29, and can calculate the tachograph constant, also called the W factor of the vehicle 11. The W factor translates the dynamics of the vehicle 11 into the displayed speed signal. The calibration device 12 can normalize the entire mechanical configuration to a standard speed signal output.

[0052] The proposed system has several key features, including: no need for manual calculations or measurements, high measurement accuracy due to the tight tolerances of the laser measuring device 13, and the ability to use the front-mounted calibration device 12 to record a video of the test, providing a high level of protection against fraud during the entire process. At the end of the test, all collected information, including raw sensor data, video, and final test reports, can be stored in the cloud on a server device 26. The data can be processed in the server device 26 and a digital certificate can be generated, making it possible to issue a certificate much faster than with the existing solution. The waste of paper and resources required to complete all this paperwork is reduced.The proposed idea can transfer the tachograph calibration process into the digital world, giving agility, accuracy and traceability to all generated data.

[0053] This invention can be used as an official calibration device in all workshops authorized for tachographs. Furthermore, since it is a portable device, it can also be used on the premises of fleet companies or at the location of any special-purpose / heavy vehicle 11, eliminating the need to transport the vehicles 11 to the workshop. The proposed invention can be applied to all electronic types of tachograph devices 10 of vehicles 11 currently on the market.

[0054] Fig. Figure 3 shows a schematic representation of the process.

[0055] A first step S1 of the method may comprise a reception of pulse signals 29 of a pulse sensor 23 of a tachograph of the vehicle 11 by the calibration device 12 during a calibration movement period of the vehicle 11.

[0056] A second step S2 may include receiving distance data 16 from a laser measuring device 13 by the calibration device 12. The distance data 16 may describe measured distances between the laser measuring device 13 and a predefined reference point of the vehicle 11 during the calibration movement period of the vehicle 11.

[0057] A third step S3 may include receiving tire gauge data from a tire gauge 17 on a wheel 18 of the vehicle 11 by the calibration device 12. The data from the tire gauge 17 may describe a rotation of the wheel 18 during the movement of the vehicle 11 and the circumference of the wheel 18 of the tire.

[0058] A fourth step S4 may include receiving camera data 21 by the calibration device 12. The camera data 21 may include images and / or a video of the vehicle 11 recorded by the camera device 20 during the calibration movement.

[0059] A fifth step S5 may include a calculation by the calibration device 12 of a distance traveled by the vehicle 11 during the calibration movement period based on the distances provided in the distance data 16.

[0060] A sixth step S6 may include a calculation of a revolution distance of the wheel 18 during the calibration movement period by the calibration device 12 based on the circumference of the wheel 18 and the rotation of the wheel 18.

[0061] A seventh step S7 may include calculating a camera travel distance traveled by the vehicle 11 based on the video and / or images supplied to the calibration device 12.

[0062] An eighth step S8 may include a verification of the travel distance based on the orbital distance and the camera travel distance by the calibration device 12. Successful verification may require that a difference between the travel distance and the orbital distance and the camera travel distance be below a predefined threshold difference.

[0063] If the verification condition is not met, the calibration device 12 may send a signal indicating that the calibration should be repeated in a ninth step S9.

[0064] If the verification is successful, the calibration device 12 can, in a tenth step S10, calculate a tachograph constant for the tachograph device 10, which describes the relationship between the number of pulses and the distance traveled by the vehicle 11, based on the travel distance and the number of pulse signals 29 received during the calibration movement.

[0065] In an eleventh step S11, the calibration device 12 may send a cloud signal 25 to a server device 26. The cloud signal 25 may include the tachograph constant and the data received by the calibration device 12 during the calibration.

[0066] In a twelfth step S12, the calibration device 12 may receive an approval message 27 indicating that the tachograph constant is accepted from the server device 26.

[0067] In a thirteenth step S13, the calibration device 12 may send a calibration signal comprising the tachograph constant to the tachograph device 10 in order to calibrate the tachograph device 10.

[0068] Overall, the example shows how an optimized and fraud-protected vehicle tachograph calibration method for short-distance tests is provided by the invention. Reference symbol 10 Tachograph device 11 vehicles 12 Calibration device 13 Laser measuring device 14 laser pulses 15 Reflector device 16 Distance data 17 Tire measuring device 18 wheel 19 Tire measuring device data 20 Camera device 21 Camera data 22 speedometers 23 Pulse sensor 24 Workshop connection device 25 Cloudsignal 26 external server device 27 Approval message 28 Calibration message 29 Pulse signal S1-S13 steps

Claims

[1] Method for calibrating a tachograph device (10) for use in a vehicle (11), the method comprising the following steps which are carried out by a calibration device (12): - Receiving pulse signals (29) from a pulse sensor (23) of a speedometer (22) of the vehicle (11) during a calibration movement period of the vehicle (11); - Receiving distance data (16) from a laser measuring device (13), wherein the distance data (16) describe distances between the laser measuring device (13) and a predefined reference point of the vehicle (11) during the calibration movement period of the vehicle (11); - Receiving tire pressure monitoring data from a tire pressure monitoring device (17) of a wheel (18) of the vehicle (11), wherein the data of the tire pressure monitoring device (17) describe a rotation of the wheel (18) during the movement of the vehicle (11) and a circumference of the wheel (18) of the tire; - Calculate, based on the distance data (16), a distance traveled by the vehicle (11) during the calibration movement period; - Calculate, based on the circumference of the wheel (18) and the rotation of the wheel (18), a revolution distance of the wheel (18) during the calibration movement period; - Verifying the route with the circuit; and - after successful verification of the distance traveled, a tachograph constant for the tachograph device (10) is calculated on the basis of the distance traveled and a number of pulse signals (29) received during the calibration movement period, which describes a relationship between a number of pulses and a distance traveled by the vehicle (11). [2] Method according to claim 1, wherein the method comprises the following step, which is carried out by the calibration device (12): - Sending a calibration message (28) which includes the tachograph constant to the tachograph device (10). [3] Method according to claim 1 or 2, wherein the method comprises the following step, which is carried out by the calibration device (12): - Check if the driving distance is above a predefined threshold. [4] Method according to any of the preceding claims, wherein the method comprises the following step, which is carried out by the calibration device (12): - Receiving camera data (21) from a camera device (20), wherein the camera data (21) comprises a video recorded by the camera device (20) during the calibration movement period. [5] Method according to claim 4, wherein the method comprises the following steps, which are carried out by the calibration device (12): - Detecting the movement of the vehicle (11) in the camera data (21); and - based on the detected movement of the vehicle (11), determining a video driving path of the vehicle (11); and - Verifying the route using the video route. [6] Method according to claim 4 or 5, wherein the method comprises the following steps, which are carried out by the calibration device (12): - Detecting the movement of the vehicle (11) in the camera data (21); - based on the detected movement of the vehicle (11), determining a route for the vehicle (11); and - Determine whether the route meets a predefined condition. [7] Method according to any of the preceding claims, wherein the method comprises the following steps, which are carried out by the calibration device (12): - Sending a cloud signal (25) to a server device (26), wherein the cloud signal (25) includes the tachograph constant for the tachograph device (10) and the data (16, 19) received by the calibration device (12). [8] Method according to any of the preceding claims, wherein the method comprises the following step, which is carried out by the calibration device (12): - Performing a user authorization process. [9] Method according to claim 7, wherein the method comprises the following step, which is carried out by the calibration device (12): - Receiving an approval message (27) from the server device (26). [10] Calibration device (12) for calibrating a tachograph device (10) for use in a vehicle (11), characterized by , that the calibration device (12) is designed for the following: - Receiving pulse signals (29) from a pulse sensor (23) of a speedometer (22) of the vehicle (11) during a calibration movement period of the vehicle (11); - Receiving distance data (16) from a laser measuring device (13), wherein the distance data (16) describe distances between the laser measuring device (13) and a predefined reference point of the vehicle (11) during the calibration movement period of the vehicle (11); - Receiving tire pressure monitoring data from a tire pressure monitoring device (17) of a wheel (18) of the vehicle (11), wherein the data of the tire pressure monitoring device (17) describe a rotation of the wheel (18) during the movement of the vehicle (11) and a wheel circumference of the tire; - Calculate, based on the distance data (16), a distance traveled by the vehicle (11) during the calibration movement period; - Calculate, based on the circumference of the wheel (18) and the rotation of the wheel (18), a revolution distance of the wheel (18) during the calibration movement period; - Verifying the route with the circuit; and - Calculate, based on the distance traveled and a number of pulse signals (29) received during the calibration movement period, a tachograph constant for the tachograph device (10) which describes a relationship between a number of pulses and a distance traveled by the vehicle (11), after successful verification of the distance traveled.

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