Automotive industry

Meeting the challenges of design complexity in the automotive industry

The automotive and transportation industry has come a long way since the patented Benz car. Car ownership has gone from being a hobby for the wealthy to a virtual necessity of modern life. And cars have changed as well, from the Ford Model T utility to today’s highly customizable, feature-rich vehicles. The Model T was a mechanical marvel in its simplicity and came out faster than any motor vehicle before. But it came with a few compromises – there was only one model and it was only available in black. Since then, a mix of customer demands, heightened competition and regulatory requirements have driven automakers to produce vehicles with more horsepower, better fuel efficiency, more cup holders and exciting new features. Today, these needs are pushing Original Equipment Manufacturers (OEMs) beyond the mechanical realm. Connectivity features, electronics and software are forcing digital transformation in today’s automotive market, and as a result, many traditional mechanical or hydraulic systems are being replaced by electronic components and software.

The divergence of automotive value from mechanical to software and electronic systems has overturned traditional methods of vehicle development, not just design tools. Mechanical systems are operated by electronic components controlled by software. Ensuring that these integrations are both accurate and reliable has become an essential aspect of modern vehicle development.

Previous orchestration methods will not withstand the rigors of modern vehicle development. Now, more stakeholders from a wider range of engineering fields must work simultaneously on systems development and integration. The documentary approach of early systems engineering efforts was increasingly challenged by the level of interconnection of products. The complexity of modern and future automobiles and transportation systems will require digitization and a solution based on the principles of Model-Based Systems Engineering (MBSE). A modern MBSE solution enable automotive and transportation companies to manage the complexity of advanced functionality, increase cross-domain integration and increasing external pressures, helping companies create successful programs.

© Siemens Digital Industries Software

More features, more complexity
The start of any vehicle program is the definition of goals, all parameters and target requirements. Will this product be an urban suburban vehicle, focusing on fuel efficiency and handling, or will it be used to regularly transport large loads? And what features are customers likely to demand? The combination of these types of questions with vehicle requirements such as powertrain type or efficiency goal constitutes a product definition. In MBSE, this is applied to the digital twin and is shared among all stakeholders. This definition, or architecture, is broadened to include the functionality needed in the vehicle – does it need an infotainment system? What driver assistance features will be included in this model?

These features are the new selling points for most vehicles, it is no longer the rated power of the engine or whether it is an automatic or manual gearbox. This change in characteristics increases the complexity of the architecture of a modern vehicle. Digital dashboard instruments require sensors for each of the displayed values, as well as a control unit to record, translate and transmit the information to the dashboard where it must then display the information correctly. This seemingly simple functionality requires integrating the mechanical systems being tracked, the electronic systems processing data, the electrical networks that carry the signals, and the software to ensure that each element works in tandem to deliver accurate information to the driver in a timely manner.

And this complexity problem increases with more integrated features. Autonomous driving systems will essentially integrate the entire vehicle into a single system – the transmission, security systems, entertainment suite and more – ensuring that they will be the most complex vehicles ever produced. And instead of working in isolation on these different subsystems until the integration phase, MBSE provides a single environment for engineers working from the system architecture. Each engineering team can work to meet the specific requirements of their systems or components, and ultimately produce specific outputs that are compatible with other vehicle systems. This approach ensures that internal teams and vendors can deliver functional components, and frequently accompanying software, that integrate seamlessly with the rest of the system.

More isolation
A key benefit of a robust MBSE approach is its ability to break down silos that have long persisted in vehicle development. Take an emergency braking function for example. The fundamental objective of such a system is to engage the brake when an obstacle is detected in the immediate path of the vehicle. To activate such a system, you need sensor data on the obstacle, information about the current vehicle dynamics, and a method to send the stop signal to the brake system to apply the brakes quickly and safely. Each of these steps involves the integration of a new subsystem or vehicle component to activate the automated braking function. Managing these connections between vehicle systems and engineering areas through traditional workflows is time consuming and opens up possibilities for miscommunication, which can lead to sub-optimal designs or, in the worst case, , to a failure.

© Siemens Digital Industries Software

Instead, MBSE makes sure everyone stays up to date while the definition is refined by different teams. This unique source of truth not only saves time and improves the accuracy of communication of design data, it also enables past work to be reused. The emergency braking system, for example, could exploit braking information already in use by an adaptive braking system so that decelerating the vehicle does not lead to loss of control. Or the vehicle dynamics information can already be tracked by another system and can be integrated with the emergency braking function to save time during development.

Understand these system interactions is also essential for the development and deployment of software in new vehicles. A single OEM can release multiple models of a vehicle in a single year, but within each model there are probably hundreds of variations of the design – these could be different feature sets or even different vendors for one piece. Whatever the exact composition of the vehicle, the on-board software managing each characteristic and function of the vehicle must be compatible and portable with all possible vehicle configurations. In the age of live updates, this challenge extends beyond the production line to vehicles in the field. OEMs will need to keep track of each vehicle and its associated software configuration to verify, validate and deploy software updates compatible with each customer’s vehicle.

Optimization and validation
Electric vehicles (EVs) and autonomous vehicles (AV) face many new development challenges compared to traditional combustion vehicles. Electric vehicles have a tighter balance between range, weight and aerodynamics due to a less energy dense storage medium. AVs will require more coding and software testing than ever before to reach level 5 of range – or full range without the need for driver interaction. The solution for many of these obstacles is simulation, perhaps computational fluid dynamics testing to determine the body’s wind resistance, or simulated scenarios for the autonomous vehicle control system to travel many more miles without time penalty. But the integration of these systems makes testing their interaction difficult, if not impossible.

MBSE provides a framework for the optimization and validation of new vehicle architectures. The range of an electric vehicle can be balanced with respect to weight and aerodynamics while also understanding the impact on vehicle dynamics. An AV system can be validated faster with more comprehensive simulation tools. Artificial intelligence (AI) can even be exploited as part of the MBSE methodology to gradually modify the virtual situation encountered by an AV system in order to increase the number of variations in driving situations in order to optimize the robustness of the system. in making driving decisions. And with the development cycle of many vehicles extending beyond the production floor, data collected from car sensors already on the road can be used to further refine driving patterns. Vehicles become a continually updated product, adding improved safety and possibly additional functionality compared to how they came off the assembly line.

MBSE for the present and the future
The complexity of vehicles increases even without the addition of mass electrification and automation. Fortunately, MBSE is designed to orchestrate this complexity. MBSE enables engineering teams and organizations to track cross-domain vehicle requirements from their initial definitions through to implementation in vehicles exiting the production line. Such a holistic view of the vehicle development process also provides opportunities for more frequent and effective collaboration within the OEM and throughout its supply chain. Through collaboration and a single, definitive source of truth, automotive OEMs and suppliers will be able to bring innovative, exciting, and high-quality vehicles to market faster and more reliably.

The cars we drive have gone from purely mechanical innovations with limited variations to a highly personalized, multidisciplinary feat of engineering. Document-based methods cannot handle the complexity of these modern vehicle programs, resulting in unacceptable development times and the introduction of potentially crippling errors. MBSE is the next step in integrated product development and can effectively coordinate multiple engineering areas and global supply chains with the digital twin to enable the advanced vehicles of tomorrow.