hardware-in-the-loop (test) (HiL)

Hardware-in-the-loop(HiL) is a test scenario used in automotive engineering, among others, in which the components to be tested are integrated into a simulated application environment.

The test components can be Electronic Control Units( ECU), which are integrated into the HiL test environment via an electronic interface, controlled with test software and loaded according to the later application. The test conditions are dynamic and should optimally simulate the later real environmental conditions. The data acquired during the HiL test is recorded, logged and evaluated, showing the behavior of the test components in the simulated environment.

The HiL test method offers advantages for regression tests of all functions of electronic control units, it is suitable for complex software tests with many operating options, as well as for testing electronic functions and for reproducing functions during troubleshooting. HiL tests can be used totest the reliability of driver assistance systems and safety systems of electric vehicles. In addition, HiL tests are intended to detect functional errors in the control software.

Other in-the-loop models include processor-in-the-loop (PiL), software-in-the-loop( SiL) and model-in-the-loop( MiL). All the in-the-loop models mentioned involve simulating an embedded system with a model that emulates the system environment.