To Test the Need and the Need to Test -Testing the Smart Controller Network for the Chassis of Tomorrow - 2008-21-0041

Hardware-in-the-loop (HIL) simulation has become a key technique for the validation of today's automotive electronics. OEMs and suppliers are investing heavily in hardware-in-the-loop equipment and tests. Typically, suppliers test the electronic control unit (ECU) as a component. The OEM on the other hand tests the ECU more from a network point of view. This paper describes the main differences between component and network HIL tests.

ZF Friedrichshafen AG has been using HIL test benches since 1985. In order to ensure high quality, especially with respect to network aspects, we not only test the ECUs as components but as part of the network. For that purpose, and to stay on the leading edge of HIL technology, ZF has set up a new test bench for networked HIL testing. The control network contains the driveline and chassis domain. The devices tested are, e.g., automatic transmission, torque on demand transfer case, torque vectoring axle drive, electric power steering, active steering system, active stabilizers, variable dampers, levelling control as well as a brake control system (ESP). This article presents the key innovations of this network test bench.

As tests are typically dispersed along the multistage supply chain between the vehicle manufacturer and several suppliers, cross-organizational test management is needed. This is the only way to ensure that all necessary tests are carried out, no tests are omitted and no redundant tests are unnecessarily performed.

Reuse is the key to efficiency. ZF Friedrichshafen employs a two-step reuse strategy which distinguishes between reuse of complete test cases and reuse of elementary test modules. This paper describes our reuse concept for test cases and elementary test modules on the basis of test libraries.