Method for monitoring the quality of a vehicle sensor

Abstract

The invention relates to a method for monitoring the quality of a component and for adapting at least one manufacturing parameter on the basis of the quality monitoring, the method comprising: - providing (S1) end-of-line quality measurement data of a predetermined batch of components; - determining (S2) a mean value of the end-of-line quality measurement data; - comparing the mean value with a predetermined batch threshold interval; and - if the mean value lies within the predetermined batch threshold interval, adapting (S3) the at least one manufacturing parameter on the basis of the mean value; and - if the mean value lies outside the predetermined batch threshold interval, adapting (S4) the at least one manufacturing parameter on the basis of a predetermined adaptation value.

Description

[0001] Description

[0002] title

[0003] Method for quality monitoring of a vehicle sensor

[0004] The invention relates to a method and / or a device for quality monitoring of a component and preferably for adjusting at least one manufacturing parameter based on the quality monitoring. Furthermore, the invention relates to a computer program with program code and a computer-readable data carrier with program code of a computer program.

[0005] State of the art

[0006] In modern vehicle technology, steering systems play a crucial role in safety and the driving experience. To ensure precise and responsive steering, modern steering systems are equipped with sophisticated steering angle and steering force sensors. These steering angle and steering force sensors are the heart of the steering system and must meet extremely precise requirements to achieve the desired steering precision.

[0007] The production of such sensors presents a significant technical challenge. Each steering angle and steering force sensor must be manufactured using a precise production process and undergo rigorous quality control. A key quality feature is the measurement of the torque deviation, which must be within a specified quality interval to ensure the functionality and reliability of the steering angle and steering force sensor and thus the steering system.

[0008] Particular attention is paid to symmetry testing within the production line for steering angle and steering force sensors. The steering angle and steering force sensors should meet a symmetry value of, for example, ± 2 Nm to meet the high quality standards. If a steering angle and steering force sensor fails to meet these requirements, it is automatically considered scrap and disposed of. While this strict procedure results in high reliability of the finished steering angle and steering force sensors, it also results in considerable scrap costs, which place both a financial and logistical burden on production. Therefore, solutions to improve quality control in the manufacture of steering angle and steering force sensors, and in particular to reduce scrap, are desired.

[0009] The invention is therefore based on the object of specifying a method and / or a device for quality monitoring of a component and preferably for adapting at least one manufacturing parameter on the basis of the quality monitoring.

[0010] The problem is solved by a method according to the features of patent claim 1. The problem is solved by a device according to the features of patent claim 10.

[0011] Disclosure of the invention

[0012] According to a first aspect, a method is proposed for quality monitoring of a component, in particular a steering angle and steering force sensor, and for adjusting at least one manufacturing parameter based on the quality monitoring. The method comprises the following steps:

[0013] - Providing end-of-line quality measurement data of a predetermined batch of components;

[0014] - Determination of an average of the end-of-line quality measurement data;

[0015] - comparing the mean value with a predetermined batch limit interval; and

[0016] - if the mean value lies within the predetermined batch limit interval, adjusting the at least one production parameter based on the mean value; and - if the mean value lies outside the predetermined batch limit interval, adjusting the at least one production parameter based on a predetermined adjustment value.

[0017] It is understood that the steps according to the invention, as well as other optional steps, do not necessarily have to be performed in the order shown, but can also be performed in a different order. Furthermore, additional intermediate steps can be provided. The individual steps can also comprise one or more substeps without thereby departing from the scope of the method according to the invention.

[0018] According to a second aspect, a device for quality monitoring of a component, in particular a steering angle and steering force sensor, and for adjusting at least one manufacturing parameter based on the quality monitoring is proposed. The device comprises an evaluation and computing device configured to perform the following steps:

[0019] - Providing end-of-line quality measurement data of a predetermined batch of components;

[0020] - Determination of an average of the end-of-line quality measurement data;

[0021] - comparing the mean value with a predetermined batch limit interval; and

[0022] - if the mean value is within the predetermined batch limit interval, adjusting the at least one manufacturing parameter based on the mean value; and

[0023] - if the mean value lies outside the predetermined batch limit interval, adjusting the at least one production parameter based on a predetermined adjustment value.

[0024] The statements made for the method apply accordingly to the device. It is understood that linguistic variations of features formulated in a method-related manner can be reformulated for the device in accordance with common linguistic practice, without such formulations having to be explicitly listed here. The present method focuses on the batch effect in sensor production. The method is particularly applicable when components are manufactured in a production line, in particular consisting of several production stations, and for which quality measurement data are recorded for at least one component parameter whose normal distribution within a production batch lies within a global limit interval or close to one of the limit values ​​defined thereby, and only some of the components lie outside this limit interval.The method, which is preferably based on static formulas, preferably carries out the adjustment step for adjusting the at least one manufacturing parameter automatically and thus preferably brings the distribution of the current batch of components into the middle of the normal distribution.

[0025] The invention relates to the manufacturing and testing of components. It improves the quality measurement process for components by reducing the NOK fractions in components that previously led to rejects. The core of this lies in the dynamic adjustment of the threshold or the mean value between the OK / NOK fractions within a continuously changing batch. Overall, rejects can thus be minimized.

[0026] Quality measurement data is preferably collected and made available at the end of the manufacturing process (end-of-line) for a continuous batch (lot) of components. This data is crucial for assessing the quality of the produced parts. The quality measurement data can preferably be recorded using a sensor. An average value (mean value) is preferably continuously calculated from this quality measurement data. This mean value serves as a representative key figure for the overall quality of the continuously changing batch. The mean value is compared with a defined quality interval. This interval defines the acceptable limits for the quality of the batch. Based on the comparison result, at least one production parameter is adjusted. If the mean value lies within the limit interval, the adjustment is made based on the mean value.If the mean value lies outside the limit interval, the manufacturing parameter is adjusted based on a predetermined adjustment value. This indicates a significant deviation from the desired quality that must be corrected. In one embodiment, a number of components in the predetermined batch of components is determined by a production line for manufacturing the components, wherein the number of components in the predetermined batch of components preferably indicates how many components are manufactured simultaneously between a start of the production line and an end of the production line.

[0027] The "number of components in a predetermined batch" refers to the specific quantity of components that are processed as a group or batch on the production line. A batch here is the number of components that are processed together. The number of components in the batch is determined by the capacity or configuration of the production line. This means that the production line is designed to process a certain number of components at the same time. The number of components refers to the quantity that is processed simultaneously between the start point (beginning) and the end point (end) of the production line.

[0028] In this case, the running average of the last N components is preferably monitored. The mean / average of these last N components is determined, and a fine-tuning of at least one production parameter is performed based on the mean. This is preferably based on the assumption that an N+1 component will be the same as the average of the last N components, so that the production parameter can be set to the absolute zero point, preferably from a symmetry perspective. Based on the large numbers of the overall production, this solution helps to bring the N+1 component within the OK symmetry range of a global quality limit interval of the production.

[0029] In one embodiment, the end-of-line quality measurement data of the predetermined batch of components is extracted from manufacturing quality measurement data comprising a plurality of batches of components.

[0030] End-of-line quality metrics are specific metrics that evaluate the quality of components at the end of the production line. They are crucial for assessing whether the components meet quality standards. A predetermined batch of components refers to a specific group or series of components considered as a single unit in production. End-of-line quality metrics for a specific batch are extracted from a larger dataset containing quality metrics for multiple batches of components. This means that quality data is first collected for multiple batches and then specific data for a single batch is extracted. Preferably, standard production samples and / or the associated quality limits are also monitored. Furthermore, average values ​​for each batch are calculated.For each batch, a small number of components, preferably more than 10 and fewer than 20, is always considered to calculate the mean value. This is preferred if such speculations are carried out based on the most recent batch volume. Furthermore, an intervention formula is preferably determined based on a failure pattern within the quality measurement data, which provides the few NOK pieces from a large volume of historical data.

[0031] In one embodiment, the predetermined batch boundary interval is within a manufacturing quality interval applicable to the manufacturing quality measurement data.

[0032] The "predetermined batch limit interval" refers to a defined range of values ​​considered acceptable for the quality of the components in a specific batch. The batch limit interval thus specifies the quality standards that the components of a specific batch must meet. The "manufacturing quality interval for manufacturing quality metrics" is a broader quality interval that applies to all manufacturing quality metrics. It represents the general quality standards applied across different batches in production. The position of the batch limit interval within the manufacturing quality interval defines that the specific interval for a batch lies within the more general manufacturing quality interval. This means that the quality requirements for a specific batch are consistent with the overall manufacturing quality standards, but may be modified.are narrowed down to take into account the specific characteristics of the batch in question. In one embodiment, the predetermined batch of components each comprises a predetermined number of recently manufactured components, and wherein the determination of the mean value comprises determining a running or moving average over the respective predetermined number of recently manufactured components.

[0033] The "predetermined batch of components with a predetermined number" defines that each predetermined batch consists of a fixed number of recently manufactured components. This number is specific to each batch and defined in advance. These are the "most recently manufactured components," indicating that the analysis focuses on the most recent components in the production line. The "determination of the mean over the predetermined number of components" means that an average is calculated for quality control purposes. However, this average is not determined from all components in a batch, but from the predetermined number of most recently manufactured components within that batch. The "running or moving average" is calculated. This means that the average is continuously updated by recalculating it for a new group of "most recently manufactured components" as more components are produced.This method enables a more dynamic and up-to-date assessment of product quality, as it reflects changes in production in a timely manner.

[0034] In one embodiment, the predetermined batch boundary interval is determined by a statistical evaluation of historical and current manufacturing quality measurement data, and wherein the predetermined adjustment value is determined by a statistical evaluation of historical and current manufacturing quality measurement data.

[0035] The batch limit interval, a range of quality standards to be applied to a specific batch of components, is established through the statistical analysis of quality measurement data. This interval specifies which quality values ​​are considered acceptable for the components in a batch. The batch limit interval can also be continuously adjusted using statistical methods. Both historical and current manufacturing quality data can be used to determine the batch limit interval. Historical data provides insight into past manufacturing results and trends, while current data provides the latest information about the manufacturing process. The data is statistically analyzed to determine the batch limit interval. This analysis can include various statistical methods to determine meaningful, reliable limits.Likewise, the predetermined adjustment value used to adjust the manufacturing parameters if the quality data falls outside the limit interval is also determined through a statistical evaluation of historical and current manufacturing quality measurement data. This ensures that the adjustments are based on sound data and take into account both past experience and current manufacturing conditions.

[0036] In one embodiment, the component comprises a steering angle and steering force sensor, wherein the at least one manufacturing parameter comprises a sensor center position correction value, wherein the end-of-line quality measurement data of the predetermined batch of components comprises torque measurement data, wherein the mean value comprises a torque mean value, wherein the predetermined batch boundary interval comprises a torque boundary interval, wherein the sensor center position correction value is determined by the torque mean value and an angle-torque constant of the manufacturing when the mean value lies within the predetermined batch boundary interval, and wherein the predetermined adjustment value comprises a maximum sensor center position correction value.

[0037] The component in this embodiment is a sensor that can measure the steering angle and / or steering force. An important manufacturing parameter is the correction value for the sensor's center position, which can be adjusted during assembly or press-fitting of the sensor components. This value is used to ensure precise alignment and calibration of the sensor. The quality measurement data at the end of the production line for a specific batch of components includes torque measurement data. This data provides information about the sensor's performance and quality with regard to torque measurement. The calculated mean value from the quality measurement data refers specifically to the mean torque value. This value is crucial for assessing the average performance of the sensors in the batch. The limit interval defined for the batch refers specifically to torque values.This interval establishes the acceptable limits for the torque values ​​considered qualitatively satisfactory within the batch. If the mean torque value lies within the specified torque limit interval, the sensor center position correction value is determined by taking into account this mean value and a manufacturing angle-torque constant. This constant reflects the relationship between angle and torque in the manufacturing process. If the mean torque value lies outside the limit interval, a predetermined maximum correction value for the sensor center position is used as the adjustment value.

[0038] The invention also claims a computer program with program code for executing at least parts of the method according to the invention in one of its embodiments when the computer program is executed on a computer. In other words, the invention provides a computer program (product) comprising instructions that, when executed by a computer, cause the computer to execute the method / steps of the method according to the invention in one of its embodiments.

[0039] According to the invention, a computer-readable data carrier with program code of a computer program is also proposed for executing at least parts of the method according to the invention in one of its embodiments when the computer program is executed on a computer. In other words, the invention relates to a computer-readable (storage) medium comprising instructions which, when executed by a computer, cause the computer to execute the method / steps of the method according to the invention in one of its embodiments.

[0040] The described designs and further training courses can be combined as desired.

[0041] Further possible embodiments, refinements, and implementations of the invention also include combinations of features of the invention described above or below with respect to the exemplary embodiments that are not explicitly mentioned. Brief description of the drawings

[0042] The accompanying drawings are intended to provide a further understanding of embodiments of the invention. They illustrate embodiments and, in conjunction with the description, serve to explain principles and concepts of the invention.

[0043] Other embodiments and many of the aforementioned advantages will become apparent upon review of the drawings. The elements illustrated in the drawings are not necessarily drawn to scale.

[0044] They show:

[0045] Fig. 1 is a schematic flow diagram of an embodiment of the present method;

[0046] Fig. 2 shows an exemplary representation of manufacturing quality measurement data without an adjustment;

[0047] Fig. 3 shows an exemplary representation of production quality measurement data with an adjustment of a production parameter; and

[0048] Fig. 4 shows an exemplary production line for manufacturing a component in a schematic plan view.

[0049] In the figures of the drawings, the same reference symbols designate the same or functionally equivalent elements, parts or components, unless otherwise stated.

[0050] Figure 1 shows a schematic flow diagram of a method for quality monitoring of a component, in particular a steering angle and steering force sensor, and for adapting at least one manufacturing parameter based on the quality monitoring. In any embodiment, the method can be carried out at least partially by a device 100, which for this purpose can comprise several components not shown in detail, for example one or more provision devices and / or at least one evaluation and computing device. It is understood that the provision device can be designed jointly with the evaluation and computing device or can be different from it. Furthermore, the device can comprise a storage device and / or an output device and / or a display device and / or an input device.

[0051] According to the invention, the computer-implemented method comprises at least the following steps:

[0052] In a step S1, end-of-line quality measurement data of a predetermined batch of components are provided.

[0053] In a step S2, an average value of the end-of-line quality measurement data is determined.

[0054] In a step S3, the mean value is compared with a predetermined batch limit interval.

[0055] In a step S4, the at least one production parameter is adjusted on the basis of the mean value if the mean value lies within the predetermined batch limit interval.

[0056] In a step S5, the at least one production parameter is adjusted on the basis of a predetermined adjustment value if the mean value lies outside the predetermined batch limit interval.

[0057] Fig. 2 shows production quality measurement data 200 of components, in this case steering angle and / or steering force sensors, for a specific number of manufactured components. The number of components is plotted on the ordinate, and a torque measured for each sensor at the end of the production line is plotted on the abscissa. According to Fig. 2, the production quality measurement data 200 have not been corrected by the present method.

[0058] Fig. 3 shows production quality measurement data 300 corrected according to the present method. The number of components is plotted on the ordinate, and a torque measured for each sensor at the end of the production line is plotted on the abscissa. It can be seen that the number of NOK components could be reduced compared to the production quality measurement data 200 shown in Fig. 2. Several batches 300 are shown, one of which is shown as an example.

[0059] Fig. 4 shows an exemplary production line 200 from above. At one end 402 of the production line 400, quality control is carried out by recording the quality measurement data. The present method is also shown schematically. Based on the method, at least one production parameter 404 of the production line 400 is adjusted. It is preferred if a connection is established between the symmetry end of line (EOL) value and the correction angle value based on the quality measurement data. If this connection can be established, the calculated intervention in the production parameter adjustment, for example, adjusting an angle, can take place. Preferably, an encryption is written that can extract the EOL values ​​and pass them on to the PLC, which can then return this value and the automatic formula and / or statistical monitoring required for the station of the production line 400.This allows for automatic response to any impact resulting from batch differences. The intensity of the intervention can be fine-tuned. A response rate can be set depending on the number of components used for averaging.

Claims

Claims 1 . A method for quality monitoring of a component, in particular a steering angle and steering force sensor, and for adjusting at least one manufacturing parameter based on the quality monitoring, the method comprising: Providing (S1) end-of-line quality measurement data of a predetermined batch of components; Determination (S2) of an average value of the end-of-line quality measurement data; Comparing (S3) the mean value with a predetermined batch limit interval; and if the mean value lies within the predetermined batch limit interval, adjusting (S4) the at least one manufacturing parameter based on the mean value; and if the mean value lies outside the predetermined batch limit interval, adjusting (S5) the at least one manufacturing parameter based on a predetermined adjustment value.

2. The method according to claim 1, wherein a number of components in the predetermined batch of components is determined by a production line for producing the components, wherein the number of components in the predetermined batch of components preferably indicates how many components are manufactured simultaneously between a start of the production line and an end of the production line.

3. The method according to claim 1 or 2, wherein the end-of-line quality measurement data of the predetermined batch of components is extracted from manufacturing quality measurement data comprising a plurality of batches of components.

4. The method according to claim 3, wherein the predetermined batch limit interval lies within a manufacturing quality interval applicable to the manufacturing quality measurement data 5. Method according to one of the preceding claims, wherein the predetermined batch of components each has a predetermined number of most recently manufactured components, and wherein the determination (S2) of the mean value comprises a determination of a running or moving mean value over the respectively predetermined number of most recently manufactured components.

6. The method according to any one of the preceding claims, wherein the predetermined batch limit interval is determined by a statistical evaluation of historical and current manufacturing quality measurement data, and wherein the predetermined adjustment value is determined by a statistical evaluation of historical and current manufacturing quality measurement data.

7. The method according to any one of the preceding claims, wherein the component comprises a steering angle and steering force sensor, wherein the at least one manufacturing parameter comprises a sensor mean position correction value, wherein the end-of-line quality measurement data of the predetermined batch of components comprises torque measurement data, wherein the mean value comprises a torque mean value, wherein the predetermined batch boundary interval comprises a torque boundary interval, wherein the sensor mean position correction value is determined by the torque mean value and an angle-torque constant of the manufacturing when the mean value lies within the predetermined batch boundary interval, and wherein the predetermined adjustment value comprises a maximum sensor mean position correction value.

8. A computer program comprising program code for carrying out at least parts of a method according to any one of claims 1 to 7 when the computer program is executed on a computer.

9. A computer-readable data carrier with program code of a computer program for carrying out at least parts of a method according to one of claims 1 to 7 when the computer program is executed on a computer.

10. Device (100) for quality monitoring of a component, in particular a steering angle and steering force sensor, and for adjusting at least one manufacturing parameter on the basis of the quality monitoring, the device (100) comprising an evaluation and computing device which is designed to carry out the following steps: Providing end-of-line quality measurement data of a predetermined batch of components; Determining a mean value of the end-of-line quality measurement data; comparing the mean value with a predetermined batch limit interval; and if the mean value is within the predetermined batch limit interval, adjusting the at least one manufacturing parameter based on the mean value; and if the mean value is outside the predetermined batch limit interval, adjusting the at least one manufacturing parameter based on a predetermined adjustment value.

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