Impact of electronics design methods in the automotive industry
Reliability is one of the key issues that designers face when creating a PCB for a transportation product. Cars and trucks are expected to withstand extreme temperatures and rigorous conditions throughout their lifecycle; and this includes the printed circuited boards and components used in the design. It is no secret that the automotive industry has faced this challenge for many years; but by adding more electronic modules, selecting the right materials and components becomes even more important. Choosing between a low-temperature, co-fired ceramic and a high-temperature FR-4 could mean the difference of a few cents or more for each PCB in the system. Taking into account the number of cars one company manufactures in a year, those few pennies can have a significant impact on the overall margin of each vehicle.
Fig. 1: Upfront system planning in a single environment addresses multiple engineering disciplines. For full resolution click here.
Reliability is also tied to the issue of the wide array of the latest features and interfaces that come with cars today. Most cars have optional navigation systems, portable music interfaces, and Bluetooth hands-free systems to choose from, and all of these options introduce a new set of concerns during product development: signal integrity, analog simulation, RF analysis, and EMC studies are becoming an integral part of the design process. What makes the problems unique for automotive engineers is that in addition to dealing with the range of power supplies introduced into the PCB that is typically seen in consumer products, they are also working with other large voltage and current supplies throughout the system of the car to make it operational.
With these elements in mind, ensuring that signal quality and cross talk interference are maintained within specifications is essential. Throw in the fact that some cars include memory and SuperSpeed USB, and engineers are now dealing with constraint management issues along with the need to conduct early analysis. This makes a case for designing right the first time and adds to the pressure of improving savings from iteration reduction.
Importance of modular design
As the options of the past, such as automatic window and door locks become standard features, and new features such as navigation and Bluetooth become the new options of today, modularized design is now a key factor in the design process. Engineers have to work together to consider how to optimize the addition of all the new features while still maintaining the physical space reservation designated for each section of an automobile. Think of a stereo and speaker unit that may come standard with a car, and the elective upgrade package that may include a rear camera or color display that manages your mp3 and voice control functions. Both the base feature and elective option must be considered in the same space reservation allocated in the car. Designers taking advantage of modular design must be cautious of this early in the design process to avoid costly mistakes.
Fig. 2: Optimize planning and partitioning of electronics systems. For full resolution click here.
Modular design also requires that other important factors such as power distribution be taken into consideration. Since the power supply systems in a vehicle are already complex, ensuring that the electronics function is not the only concern–the car still needs to start every time and use the battery in the most efficient way. That is why some car models have the option to upgrade to specific features and others do not. If you try to add an aftermarket device to your car, the warranty may become null because manufacturers cannot guarantee that the existing power distribution can support the power consumption of new devices. As engineers address these types of issues during the design process, identifying the proper specifications of acceptable modules becomes vital to ensure the automobile operates correctly. Also, it is important to understand which options, modules, or after-market parts will violate operation specifications to protect manufacturers from warranty disputes.
With the use of modular design, design teams can leverage design reuse from one model to another. As long as space reservation and reliability concerns are addressed, most modules can be reused effectively to allow manufacturers to deliver new products to the market on time. The automotive industry comprises a vast network of suppliers and partners who work together during all facets of product development, from engineering to production. As each player in the process leverages reuse, the cost savings benefits quickly mount up–helping auto manufacturers retain a competitive edge, and allowing suppliers to hold their ground as partners by providing cost-efficient solutions to the overall vehicle production process.
Aligning data management to the design process
Along with the other integral pieces in the automotive design process, data management is a crucial element. Consider all the steps in the process and all the contributors involved with production; data management is a necessity and is the major element that ties the whole process together. Of particular concern in this area is the supply chain. Most manufacturers have adopted “just-in-time” methodologies and lean six sigma processes, ensuring that you have access to the right, qualified component, and information about its availability, meaning that parts can be shipped at a specified time. So linking your domain data management system and the procurement system tightly with the supply chain has key benefits when making design decisions during product development.
Fig. 3: Address the complex challenges of system-level design
Data management also plays an important role when interacting with the suppliers and partners that are part of the product design cycle. Many times, design data is shared between several companies and worked on concurrently by multiple design engineers, so keeping track of your work in progress (WIP) and securing your data when needed is vital. This is also a key concern in the automotive industry because of the competitive and sensitive nature of the business. Most automotive manufacturers have become truly global companies in the past 20 years or more. Having the proper data management system in place affords companies the flexibility to securely design anywhere and manufacture anywhere while maintaining the required delivery to market.
Optimizing the complete electromechanical design
Engineers, whether they are focused on the mechanical aspects of an automotive design, or the electrical or electronic aspect of product development, must always take into account the overall design of the complete system. Designing a vehicle requires a holistic view of the system at several levels. The operation of each system within the design discipline in itself, and the operation of the system as a whole unit have to be purposefully planned and examined early on in the design process. Being able to effectively design from concept to manufacturing is another area where engineers are looking for opportunities to improve. Many times, violation of space reservation and minding other factors such as cost, weight, and power consumption are identified too late in the design process. System planning tasks such as bill of material planning, functional diagrams, and 2D and 3D space planning of the entire system, or each sub-system is an area where engineers can take advantage of working in a single environment.
Linking the planning information to the electronic and mechanical design phase increases efficiency by saving time through using the planning data to initiate the detail design, and reduce errors by maintaining design intent. Integrating these tasks and reusing information, whether it is conceptual or for the detail design, adds benefits of cost reduction and improvement of overall quality to the product development cycle.
Fig. 4: Drive engineering intent from product planning to multi-board layout
Because of the presence of more electronic components in automotive design, the complete behavior of the system requires attention, and simulation and analysis play vital roles at this stage. At this point, the concerns are beyond signal quality or EMI. Analysis areas such as thermal, hydraulic, and even pneumatic studies have to be conducted early in the process to avoid costly mistakes that may normally be identified only after prototypes are produced. When system-level simulation is performed before the physical design takes place, the complete design process benefits.
With ever increasing challenges faced by the automotive industry as more PCBs are now part of the complete electrical and electronic system, new complexities are added to the already challenging design process. With these complexities come new opportunities for process improvement. Designing a car or any other motor vehicle involves the more familiar issues of reliability and modular design reuse, while at the same time entails newer concerns such as data management and the conceptual planning and design of the complete electromechanical system.
Many of the issues discussed can be addressed by modern EDA companies who specialize in electrical and electronic design, and understand how the importance of domain data management can provide value to the overall process. To remain profitable and competitive, it is imperative that both automotive manufacturers and their suppliers engage in partnerships with trusted vendors to help improve the existing design process and be ready for any future changes. By establishing these trusted relationships, many of the benefits and savings can be achieved through collaborative working practices.
About the author: Humair Mandavia is a Senior Technical Marketing Manager at Zuken, Inc., focused on the areas of System Level Design with emphasis on High-speed/SI and ECAD/MCAD collaborative solutions. He started with Zuken in 2004 as an applications engineer, and prior to that, worked as a hardware design engineer in the telecoms industry. Mr. Mandavia graduated from the University of Texas at Dallas with both a B.S. in electrical engineering and an MBA. He can be reached under Humair.email@example.com
Source for all images: Zuken