To keep pace with the constantly increasing complexity, meet customer requirements and uphold the brand-specific characteristics, the development of steering systems necessitates extensive and continuous tests. The Steering-in-the-Loop test bench from IPG Automotive allows to test future steering systems, such as steer-by-wire, today – reproducibly and without any risks.
Not every company in the field of steering system development owns a test bench for this type of component. The reasons are manifold: For single-project assignments for example, there is no use for the test bench in the long run. Also, due to the lack of test possibilities before the investment, entrepreneurs often back away from the high acquisition costs for an own test bench.
In these situations, IPG Automotive offers the possibility to rent a Steering-in-the-Loop test bench on site in Karlsruhe and to test steering systems. IPG Automotive performs the mechanic, electric and software-related integration of the respective steering system into the test bench and monitors the test process during the entire rental time. Additional customer-specific measurement or calibration software can be coupled with the test bench if necessary. After defining the test plan, a maneuver catalog is created for the test procedure. Required scenarios are build and tests automated. Afterwards, these scenarios are simulated and, in the final step, test results are analyzed and documented.
This test bench enables tests for steering systems based on EPS (electric power steering) that support the steering command electromechanically as well as for steer-by-wire systems that forward the steering command electrically without a mechanical steering column. Independently from the steering system type, a variety of test have to performed during the development process. Function tests focus on the inherent effect of the steering system functions.
Nowadays, these tests play a significant role because a growing number of advanced driver assistance systems (ADAS) impact the lateral vehicle control. The steering system is therefore crucial for ADAS. One example for ADAS are lane keeping assist systems (LKAS). In the past, the driver obtained a haptic warning from the steering wheel thanks to the lane departure warning system (LDWS) when leaving the lane unintentionally. Nowadays, vehicle manufacturers integrate LKAS that actively intervene in the steering. The ongoing development of LKAS aims at holding the vehicle in the right lane but also at driving in the middle of the lane. Potential collisions caused by the vehicle leaving the lane are prevented through a greater steering intervention by the emergency lane keeping system (ELKS). The Steering-in-the-Loop test bench allows for comprehensive testing of the functionality of these and other ADAS with lateral control. Tests that can also be performed on the Steering-in-the-Loop test bench are fail-safe tests. They simulate the failure of a sensor signal, short circuit or loose contact for example. Performance tests allow to push the performance of the steering system and its functions to the limits and to carry out tests under these conditions as well. In addition to these tests for steering development, another application possibility of the Steering-in-the-Loop test bench is the parameter identification for the Pfeffer steering model. It allows to generate an exact model of the real-world steering system to create a virtual prototype for MIL and SIL tests.
The test bench from IPG Automotive also offers options such as the Driver-in-the-Loop platform (DIL) as well as the Hands Off Clutch. With DIL, a real driver can manually give steering commands, evaluate the steering feel and sense haptic feedback from ADAS. Our Hands Off Clutch device developed in-house simulates letting go of the steering wheel during the test runs. This allows to test ADAS that intervene in steering and take over the steering wheel at least temporarily. Examples are lane keeping assist systems (LKAS) or park assist systems.
The test bench from IPG Automotive in Karlsruhe therefore allows to test complete real-word steering systems, to identify weak spots at an early stage and to improve and validate them if necessary. For easy, direct testing of your systems, without high acquisition costs or investment risks.