Designing a new car – the TMG Way
Everything is designed to a greater or lesser extent. A new consumer device, some complex new medical equipment or a new aeroplane all involve a lot of compromise, but perhaps none more so than the design and development of a racing car. The trick in producing the best result is to combine the finest tools available with proven knowledge and experience, which together make for a more efficient development cycle.
For the creation of the TS030 HYBRID racer, which will compete in this year’s FIA World Endurance Championship, TOYOTA Motorsport GmbH (TMG) utilised some of the best design and development tools in the world of motorsport, as well as many years’ experience of cutting-edge projects. Chris Hebert, Head of Aerodynamics at TMG, discussed about how the innovative Le Mans challenger was designed and developed from a scratch in time for the team’s first race at Spa in May. He said: “While the primary performance drivers of the new car are the hybrid system and the aerodynamics, it is also the complex interplay of how these impact other factors such as tyre performance that will ultimately determine the success of the design.”
The task of car design combines calculation, design and experimentation. Rarely does it start with a completely clean sheet or even screen. The regulations and key design points of competitors’ cars provide some starting points. In the case of the TS030 HYBRID, the hybrid powertrain had already been tested to an advanced stage while an early decision to choose a closed cockpit was taken together with fundamental design elements such as wheelbase. These decisions were made to optimise aerodynamic efficiency, structural rigidity, weight distribution and stability.
While the aero experts focus on the outside, the specification and packaging of the major systems, such as cooling, are being considered by other engineers. As Chris Hebert points out: “The use of hybrid technology brings additional penalties in the form of cooling and packaging that require design compromises. The size and location of radiators to cool the internal components is one element, but the super capacitors for storing the hybrid power generate a lot of extra heat. They are located inside the cockpit so it is also necessary to provide the drivers with a reasonable working environment. These are just some of the considerations that need to be taken into account as the TMG design team developed initial concepts.
Optimisation of designs from bodywork to systems and sub-systems begins as soon as the first design elements are in place. Here engineers use Finite Elements Analysis (FEA) software to model the stresses that parts will experience on the race track. Of course the priority is often how light and small can a part be made while still being strong enough to do the job reliably for 24 hours of racing. Everything from suspension and drive-shafts through to engine mounts and gearbox casings go through this same process of optimisation and weight reduction without compromising on functionality or stiffness.
Analysis of this strength-to-weight compromise depends on the material being used for the part and whether that is machined metal - such as aluminium or titanium - or whether it is constructed of composite materials. Software analysis is programmed to cover all variables. TMG engineers have extensive experience of high-performance composite design, including structural items and impact absorption structures with both static and dynamic load testing. The analysis is sophisticated enough to analyse the different ways of layering carbon fibre and other composites to create strength without adding unnecessary weight.
Another area of TMG expertise that helped create the TS030 HYBRID was hydraulic systems development. Again the combination of skilled engineers and sophisticated software enables the design and simulation of complex systems ranging from servo valves and pumps through to engines, gearboxes, water coolers and oil coolers. By developing these in the virtual world first, the design team can reduce development times by cutting the number of real world manufacture and test cycles.
For the TS030 HYBRID, as with all projects, TMG has brought together three key ingredients to create the best environment of success. First are the people with the right skills and experience to make the right design and development decisions. Second are the technology and facilities. With advanced computing power and software including Catia V5 as well as Tosca, Genesis, ANSA, Abaqus, Nastran, LSDyna (crash applications), LMS Virtual.Lab, LMS Imagine.Lab, AMESim and Matlab plus extensive “live” test facilities, TMG can ensure that the design will function and perform as intended. Finally and perhaps most importantly is the synergy between the different departments to ensure the design and development processes are integrated and that conflicting requirements are balanced into an appropriate design compromise.
At TMG, the design and engineering process is totally focussed on delivering speed, both in terms of process and the end product.