The ACP Process TM Applied to the FutureSteelVehicle Project : The Future of Product Design and Development

WorldAutoSteel launched Phase 2 of its FutureSteelVehicle programme (FSV) with the aim to help automakers optimise steel body structures for electrified vehicles. The Phase 2 objective is to develop detailed design concepts and fully optimise a radically different body structure for a compact Battery Electric Vehicle (BEV) in production in the 2015-2020 timeframe. This paper will provide an overview of the product design methodology and how it was applied to WorldAutoSteel FutureSteelVehicle (FSV) program and result in 35% BIW mass reduction and how it has continued to evolve with each application. The Accelerated Concept to Product (ACP) ProcessTM was applied in this project. The ACP ProcessTM is a proprietary, performance-driven, holistic product design development method, which is based on design optimization. ACP incorporates the use of multiple CAE tools in a systematic process to generate the optimal design solution. The ACP ProcessTM is a methodology that provides solutions, which address the challenges facing the modern product development environment. It achieves this by synchronizing the individual facets of the product development process, resulting in an overall reduction in development costs and time to market. Material selection and utilization, product performance requirements and manufacturing and assembly processes are all considered as early as possible in the design cycle. The resulting design offers a robust and highly efficient solution; which when combined with the strength and design flexibility of Advanced High Strength Steel (AHSS) or other materials; facilitates significant mass reduction for the final design. For the development of a vehicle structure, the methodology offers four key benefits, including a demonstrated capability to reduce product development costs by 40%, reduce product mass by 25% and more, improve product performance (stiffness, durability, NVH, crash/safety, durability) as well as improve fuel efficiency based on the mass reduction results. The paper will further disclose the results of the FSV programme, detailing steel body structure concepts for the aforementioned vehicles that meet aggressive mass targets of 190 kg, while meeting 2015-2020 crash performance objectives as well as total life cycle Greenhouse Gas emissions targets. FSV’s steel portfolio, including over 20 different AHSS grades representing materials expected to be commercially available in the 2015 – 2020 technology horizon, is utilised during the material selection process with the aid of full vehicle analysis to determine material grade and thickness optimisation. Achievement of such aggressive weight reduction with steel will set a new standard for vehicle design approaches for the future. Radically different powertrains, such as the BEV and the PHEV proposed for FutureSteelVehicle, and their related systems make new demands for increasingly efficient body components to handle the new loads. This will require innovative use of AHSS grades and steel technologies to develop structures that are stronger, leaner, greener and affordable. The presentation will explain the “state of the future” design optimisation process used and feature the aggressive steel concepts for structural subsystems incorporated into the FSV structure. INTRODUCTION The automotive industry is facing numerous challenges today. The product design and development process includes multi-dimensional issues, which often contradict each other. A central challenge is the need for cost reduction to compete in the global market, while continuing to meet all new and existing requirements for quality and performance. The cost reduction objective is challenged by a few factors, including aggressive fuel economy and emissions standards. Other factors include new crash safety requirements, increasing customer demands and expectations for quality and performance and the availability of new energy sources such as electric/hybrid vehicles, plug-in technologies and fuel cells. While today’s criteria for a vehicle’s environmental performance stresses fuel economy and tailpipe emissions, a more comprehensive approach is required to address the vehicle’s total carbon footprint. This is accomplished with a Carbon Dioxide Life Cycle Assessment (CO2 LCA) approach that measures the carbon dioxide emissions associated with all phases of a vehicle’s life. The key benefits of ACP ProcessTM are shown in Figure 1. Figure 1: ACP ProcessTM Benefits These requirements indicate that new approaches are necessary. Over the past 10 years, new technologies and techniques have been developed and implemented within industry research projects. The development and availability of some key enablers have also emerged, leading to a new design optimization based technique referred to as the Accelerated Concept to Product (ACP) Process. ACP views vehicle development in a completely holistic way. An approach such as this ultimately reduces the number of prototypes and tests, thereby reducing overall development costs. THE ACP PROCESSTM In order to most effectively explore the design space (design volume, material and manufacturing process), while trying to reduce design cycle times, engineers are now using an automated design multidiscipline optimization-based process, called the Accelerated Concept to Product (ACP) Process. This process can help them to evaluate hundreds of design concepts, finding a set of acceptable design solutions that also contain the optimal or near-optimal design solution. ACP is a holistic design process that investigates the entire design space available to define the most robust design solution. The tools within ACP can greatly decrease the time required to identify a set of feasible, or even near-optimal, designs prior to building and testing the first prototype. Moreover, ACP can also compensate for the limitations of human intuition and provide design engineers with the freedom and power to seek creative solutions that are not obvious to even the most experienced engineers. KEY ENABLERS OEM’s and software companies have developed many virtual tools to reduce cost in the product design and development process. Such virtual approaches primarily use Computer Aided Engineering (CAE) methodologies, mostly based on the Finite Element Method (FEM). All these virtual tools or environments try to connect Design, CAE and Manufacturing while reducing cost. The ACP ProcessTM uses several software tools such as an optimization code, CAD parameterization, Modeling/morphing, FEM solvers (static and crash), pre/post processors and formability/stamping solutions. The availability of new, fast and low-cost hardware such as the High Performance Cluster (HPC) System is another key ingredient for this type of approach to cost reduction. Another key focus is on the availability of new and advanced manufacturing processes. It can be thought of as the road map to achieving more affordable, safer, lighter weight and environmentally friendly vehicle (Figure 2). Additionally, new advanced materials offer solutions for cost reduction, while addressing mass reduction and the need to meet the latest fuel economy and emissions, such as CAFÉ standards. Aluminum, composite materials and even magnesium are being aggressively investigated for mass reduction with multi-material solutions, challenging the steel industry to enable additional mass reduction capability with steel for the vehicle body-in-white (BIW) and closures. This is the new direction in the automotive industry and the FutureSteelVehicle program was initiated by WorldAutoSteel to respond to this challenge. Product development challenges of this magnitude require a new process that incorporates all of these enablers implemented at the initial stage of product design and development. Combining these key enablers with the ACP ProcessTM has proven that the mass can be reduced by at least 15-20%. This paper will describe the ACP ProcessTM and illustrate how it has been successfully applied to the product design and development of two research projects: The Future Generation Passenger Compartment (FGPC) and Future Steel Vehicle (FSV). Figure 2: ACP Enablers ACP PROCESSTM METHODOLOGY The ACP ProcessTM is a holistic product development process with multi-disciplinary loading based on topology optimization and geometry, grade and gauge (3G) optimization. Using multiple CAE tools; including modeling tools, application-specific tools, solver technology and optimization solutions; CAE, design and manufacturing are all synchronized. Once an optimal concept is identified, the ACP ProcessTM further generates the design, analyzes it and optimizes it using loading, manufacturing, material and cost constraints. It then outputs Computer Aided Design (CAD) data of an optimized concept design, suitable for detailed design and manufacturing. Figure 3 illustrates the difference between the conventional and ACP ProcessTM approaches to product development. Figure 3: Current Product Development & ACP Process TM Comparison The process can be applied to product development in two ways: 1. Clean Sheet Product Design First, ACP can be applied for a clean sheet design (development of a brand new product). For this type of product development, engineers start from A-class surface and occupant space. The WorldAutoSteel FSV project applied the enhanced optimization approach conducted for the pilot project to a full vehicle body structure while addressing metal forming and assembly capability. FSV addressed electrified vehicle powertrains, consider a technology horizon of 2020 and set a mass reduction target of 35 percent. This aggressive mass target will be achieved by leveraging the advanced steel grades, advanced steel manufacturing technologies and advanced design optimization using ETA’s ACP ProcessTM steps 1-4 ( Figure 4). 2. Product Design Refinement ACP can be applied for existing product refinement . In this case, engineers start with