Dynamic Steering Force Emulator: Paving the Way for ADAS/AD Validation

On June 23, 2023, AVL announced that the first AVL DRIVINGCUBE™ in the United States is now operational at the Clemson University International Center for Automotive Research (CU-ICAR). This article showcases and provides a closer look into a key component that enables the unique capabilities and benefits of the AVL DRIVINGCUBE™.

Augmenting the ViL Approach

Traditionally, Vehicle-in-the-Loop (ViL) systems use vehicle testbeds where vehicles are steered virtually rather than physically. However, when validating advanced driver assistance systems or automated driving functions (ADAS/AD) that involve lateral dynamics, such as Lane Keeping Assist (LKA), it is important to be able to steer the vehicle physically. It is imperative that the steering system operates in a realistic load situation. The AVL DRIVINGCUBE™ extends the traditional ViL testbed by incorporating the Dynamic Steering Force Emulator (DSFE), allowing highly dynamic, full range steering, for the driver and the ADAS/AD function.

What is the Dynamic Steering Force Emulator?

Together with STÄHLE, our strategic collaborator, we established new testing opportunities with our patented steering technology. We can now perform steering on the testbed under safe and reproducible conditions at vehicle level. The AVL DRIVINGCUBE™ paves a new way to accelerate the validation and approval process of ADAS/AD systems.

The Dynamic Steering Force Emulator (DSFE) is a compact and retrofit solution that is applicable at all types of chassis dynamometers and powertrain testbeds. It allows for full range of steering capability with accurate force feedback from the virtual road. When attached to the vehicle, it is used to validate ADAS/AD functions that require realistic steering like LKA systems.

Furthermore, the DSFE is designed in such a way that it can be mounted on most vehicles. The steering rods of the vehicle are decoupled from the wheel carrier and connected with the force actuator of the module. The steering motion of the tire is blocked by connecting wheel fixations between the wheel carrier and the chassis.

Installation and Specifications

The DSFE can be attached to the underbody of the vehicle, only extending 140mm below the underbody, and is therefore applicable for many passenger cars, while on chassis dyno. The actuation speed is about 250mm/s at the steering rack, and it reaches about 5kN of maximal force. This is sufficient for driving most highway and urban scenarios. With 180mm of travel range, it covers the full steering angle of most passenger cars. The solution has proven excellent correlation results between on-road or proving ground test and ViL test.

User Perspective: Clemson University

Research teams will leverage AVL’s system to advance virtual prototyping and digital engineering for autonomy-enabled ground vehicles as part of Clemson University’s Virtual Prototyping of autonomy-enabled Ground Systems (VIPR-GS) center.

Seth Schofill, Powertrain Electrification Research Associate at Clemson University, commented: “The DSFE currently installed on a Level 3 Autonomous Chrysler Pacifica is modular and flexible, allowing Clemson University to adapt it for use on other vehicles for research beyond the Pacifica. Our test vehicles are required to be tested both in ViL environments as well as in the real world. The DSFE allows us to interchange between simulated-dyno testing and on-road testing with minimal turnaround time.”

“With this solution, researchers can better understand and optimize ADAS/AD functions involving lateral controls and vehicle dynamics while interacting with a simulated environment,” said Seth. “The use of the DSFE makes testing of ADAS/AD equipped vehicles more feasible while on a fixed dyno testbed. Our team is looking forward to exploring its capabilities for various scenarios and ADAS/AD functions.”  

Industry Perspective and Event

Experience these ADAS/AD testing and validation solutions firsthand as AVL and CU-ICAR present an industry event: Exploring the Digital Proving Ground on September 15, 2023, at the CU-ICAR campus. As part of the program, attendees will be invited to a complete facility tour and a live demonstration of the AVL DRIVINGCUBE™.

Explore the technology: For specifics and other features of the AVL DRIVINGCUBE™, please visit www.avl.com/en/testing-solutions/automated-and-connected-mobility-testi….

Discover AVL’s ADAS/AD Solutions: www.avl.com/adas.