Key to vehicle production, particularly electric vehicle production, is the stage of production compliance control and quality control of correct vehicle assembly. In the automotive industry, especially in the production of components for passenger cars, the rate of detecting defective components is measured in parts per million – such a low error rate is required because these vehicles are produced in millions and consist of several thousand components, thus any significant failure rate cannot be tolerated. Failure of a key component in just one passenger vehicle can lead to a fatal accident. Therefore, verification of individual components before assembly in the vehicle as well as control of the entire vehicle after assembly is crucial.
The device used for verifying the quality of assembled vehicles is called an End of Line Tester (EoL). This device is used to verify that all onboard systems are functioning correctly and safely.
As part of projects commissioned by a heavy-duty vehicle manufacturer, we have designed and programmed an End of Line tester, which is a key element of the quality control process for these vehicles.
The tester is equipped with an interface for communication with the vehicle through the OBD diagnostic connector and has a module for checking the insulation levels of individual zones of the high-voltage installation. During the vehicle checking process, the insulation tester is connected to defined points on the vehicle chassis. Additionally, the charging socket system is checked by connecting the charging plug to inspect the individual high-voltage wires and their insulation levels.
Vehicle identification is performed using a code reader, which identifies the vehicle and assigns measurement results to a specific VIN number to ensure traceability of measurement results with the vehicle.
The vehicle checking process is very precisely defined, and the quality control worker follows the steps of instructions displayed on the device, while confirming the correct and safe execution of tasks – this is a very important feature of this device as it helps to avoid hazardous behavior and informs the worker about potential risks. It should be noted that the device generates 1000 V DC voltage during the testing process.
The tester has also been integrated with a dynamometer and an axle pressure measurement system, so that the result of the final quality checking process is automatically generated report compiled with measured values – this additionally verifies the correctness of the entire vehicle construction.
The provided device fits into Industry 4.0 solutions and is part of the digitalization and digitization of production, while also allowing for reduction of production costs and costs related to complaints. Such a system also shortens the production time of the entire vehicle, as the checking process is automated.