Using model-based systems engineering to develop a comprehensive digital twin of ADAS features

MBSE approach

The global autonomous vehicle (AV) market is growing rapidly. Statista estimates that by 2025 the market will be worth nearly $400 billion. FIH Mobile, a subsidiary of Hon Hai Technology Group (Foxconn), has become most well-known over the past few decades for its vertically integrated, end-to-end design, development and manufacturing services for handsets, mobile and wireless communication devices and consumer electronics products. Seeing an increasing demand for new emerging technologies, FIH Mobile extended its expertise to the advanced driver assistance systems (ADAS) and AV markets.

In 2021 FIH Mobile partnered with Stellantis, a leading global automaker and mobility provider, to develop a joint venture with Mobile Drive Technology Co., Ltd (MobileDrive). MobileDrive develops infotainment, telematics and a cloud service platform with ancillary hardware and software. Aiming to rapidly deliver the highest quality software to fulfill market demands, MobileDrive selected Simcenter™ Engineering and Consulting services to assist in developing a model-based systems engineering (MBSE) approach to support its ADAS ambitions.

MobileDrive realized that Simcenter Engineering could help them leverage a robust digital thread that would allow them to capture data to optimize systems across all key domains.

A strategic ADAS partner

Developing ADAS requires extensive knowledge and experience in applications and functional safety. Simcenter Engineering has proven expertise in these areas so it was an excellent fit for MobileDrive.

MobileDrive’s primary interest was to learn how to use a model-based framework to develop the algorithms and software controls for common ADAS applications, such as lane keep assist (LKA), lane keeping and emergency steering assist (ESA). They selected Simcenter Engineering to act as a technology partner to develop these capabilities and provide their engineering staff with the required software expertise.

Two goals, one ADAS vision

MobileDrive’s initial goal is to become a trusted partner of Chinese and Taiwanese original equipment manufacturers (OEMs) in developing their ADAS application software. In the future, MobileDrive’s goal is to be a leading automotive electronics supplier.

To help MobileDrive achieve these goals, Simcenter Engineering created a roadmap to help the company transition to the MBSE approach, starting with supplier and OEM requirements, then cascading these down to the software requirements.

The teams agreed to develop six features, including LKA, emergency lane keeping (ELK), lane following control (LFC), auto lane change (ALC), ESA and autonomous emergency steering (AES) as part of the first lateral controller to help MobileDrive meet its ambitious time-to-market goal.

“We needed a good understanding of the basics from the Simcenter Engineering team, including how to deliver on requirements and how to build the initial architecture,” states Winston Hsu, chief technology officer (CTO) at MobileDrive. “We also needed to understand best practices for writing and managing use test cases in order to guide software development.”

Simcenter Engineering provided a complete methodology and road map for MobileDrive’s ADAS vision, including writing the functional and technical safety requirements, performing functional safety tests, generating the test cases and developing and testing the system based on simulation models using Simcenter Amesim™ software, a leading systems simulation platform, and Simcenter Prescan™ software, Siemens Digital Industries Software’s virtual ADAS validation package. Additionally, they provided full requirements traceability using Siemens’ cloud-based application lifecycle management (ALM) tool, the Polarion™ portfolio. The Simcenter Engineering team also conducted a full technology transfer using Polarion to make sure MobileDrive could replicate the technology in-house. Simcenter Engineering and these products are part of the Siemens Xcelerator business platform of software, hardware and services.

Building the simulation models

This project required the Simcenter Engineering team to build a detailed vehicle dynamics model to validate the lateral controller. To accomplish this, Simcenter Engineering experts conducted market studies to define the system requirements based on full vehicle requirements.

Simcenter Engineering then applied this knowledge and their extensive experience in ADAS to model all vehicle dynamics and provide a virtual test environment for verifying the controller. By coupling Simcenter Amesim with Simcenter Prescan, the team was able to define the environment for different driving scenarios, including those related to functional safety. The virtual environment also allowed the system to incorporate the various ADAS sensors, such as cameras and short- and long-range radar used for sensor fusion as part of the ADAS control feature. The controller was then integrated into the virtual testing environment, where several features were tested in a closed-loop framework between the different software platforms.

This framework gave the teams the ability to observe the product as a comprehensive digital twin. This was extremely valuable as they used the information to quickly uncover both system and software performance issues, allowing them to address these items early in the development cycle.

Tracking requirements

The use of Polarion played a key role in this project. The Simcenter Engineering team used it to store all levels of requirements from many different sources such as use cases, customer needs, OEM needs, system, software, functional safety and failure mode requirements. These requirements were then cascaded and decomposed to develop software architecture and software feature requirement specifications that were implemented using Simulink for model-in-the-loop (MiL) closed loop testing. Simcenter Engineering also leveraged Polarion capabilities to maintain and capture the many verification tests used to verify the control software by providing complete traceability between requirements, test cases and technical safety requirements. This supported MobileDrive’s desire to be compliant with Automotive SPICE (ASPICE) and International Organization for Standardization (ISO) 26262 regulations.

Simcenter Engineering used Polarion to create test cases for all the requirements, show traceability between the test cases and the requirements and execute them in a closed-loop simulation using the Simulink controller with Simcenter based vehicle and traffic models. These results were then automatically brought back into Polarion to provide both the MobileDrive and Simcenter Engineering teams with a dashboard that provided real-time metrics on the pass/fail criteria and key performance indicator (KPI) parameters. This allowed the project management team and others to actively assess in real time how many requirements passed or failed their verification tests.

Next, the Simcenter Engineering team made sure the communications between Siemens and MobileDrive could be synchronized by hosting the Polarion server in the cloud. This streamlined the communications between the teams and gave them the ability to ask questions, exchange data and view dashboards in a single location.

The cloud solution also allowed both teams to remotely review, comment on and approve requirements either individually or collectively.

Once the simulation phase ended, MobileDrive put the results to the test in their electronic control unit (ECU). “We were pleased to discover the MBSE approach provided by Simcenter Engineering was extremely successful,” states Burt Chen, project manager at MobileDrive. “The functionalities all worked as promised and this gave us the confidence to deliver high-quality software to our OEM.”

More than just a developer

At the end of the project, Simcenter Engineering provided an implementation and technology transfer to MobileDrive. This was done in training sessions in which the Simcenter team conducted multiple hands-on workshop forums to assist the MobileDrive team on the use of the MBSE framework. The team also transferred all the Polarion projects to make sure that MobileDrive would have full visibility into their requirements and can easily replicate them for future development.

The Simcenter Engineering team’s top priority during these technology transfer sessions was to demonstrate to MobileDrive the best practices within the industry, how to efficiently solve problems using a virtual testing framework and how to convert the software into their own development and production environments. Every model, dashboard and technique was designed to be directly used in MobileDrive’s production, easily updated and even scaled up depending on customer requirements.

Using MBSE and the digital twin

“Simcenter Engineering provided us with industry best practices for developing and using MBSE throughout the V-diagram,” says Chen. “We now have a full understanding of how to accelerate our algorithm and verification activities for product development. Using Polarion also showed us how we can be more compliant and structured in order to meet functional safety standards, such as ISO26262.”

In total, the MobileDrive and Simcenter Engineering teams spent 1.5 years developing the features, training and exchanging technology.

Using Polarion gave MobileDrive the ability to make changes to the controller software requirements on-the-fly rather than needing to go through a supplier. With Polarion, MobileDrive has constant access to its own requirements, which they can build on, change and use as an asset rather than repurchasing them from a supplier.

Ultimately, MobileDrive reduced the ADAS product timeline before a physical prototype was even built. This was due to their newfound ability to verify ADAS software features early on in the comprehensive digital twin environment using Simcenter Amesim and Simcenter Prescan rather than performing hardware-in-the-loop (HiL) test benches or on a test track.

“MobileDrive’s ultimate goal is to be the leading provider of ADAS ECUs,” says Hsu. “Thanks to our partnership with Simcenter Engineering, we anticipate that we will be able to bring these ECUs to market in a much more streamlined, efficient manner.”