Until recently, the choice of transmissions available to automotive vehicle manufacturers was limited to either a conventional manual or a planetary automatic with torque converter. In a typical development process, these transmissions were largely developed in isolation from the engine and the rest of the powertrain and vehicle.
Over the last 15 years however, there has been significant growth in both the number of transmission types available and also their complexity. Today these include manual, conventional automatic, dual clutch, automated manual, continuously variable, split power and pure EV transmissions. Alongside this growth in gearbox technology, most manufacturers are now simultaneously developing conventional, hybrid and all electric vehicles with each type requiring different driveline architectures.
The continuous drive to deliver optimal efficiency alongside reduced weight and cost, has also meant that newer powertrains now feature much closer integration of the gearbox, prime mover and energy recovery systems and rely on sophisticated control systems to ensure optimum performance and efficiency is delivered at all times.
This shift in technical complexity has occurred against a backdrop of increased competition and global financial uncertainty. More so than ever before, vehicle manufacturers have been forced to innovate and bring to market powertrains that are novel and therefore comparatively unproven. There is also a real need for new vehicles to maintain the brand attributes which is so important for manufacturers wanting to differentiate their products in an overcrowded market. For the engineering teams tasked with developing these new powertrains, resources are being pushed harder than ever and development processes are now very much under scrutiny.
Although CAE has been widely used in driveline development for quite some time, the underlying development processes in which it is used, often remain largely unchanged. This means that components and subsystems are still be being designed in isolation by siloed parts of the organisation, which favour proven component level analysis tools.
Whilst the sophistication and accuracy of these tools is not in question, the fact that many calculations are made without considering the effects of the entire system, can lead to the creation of sub optimal designs which are compromised by problems which are then difficult and expensive to correct. For example, it is not uncommon for powertrain noise and vibration issues to go undetected until the first hardware prototypes have been tested.
A further issue which can compound the problem is the transfer of data (or lack of) between different design and analysis tools. In some cases, basic concept design changes can take weeks to ripple through various departments, often requiring manual updating of models which is both slow and error prone. This inertia within organisations is a major hindrance to the creation of optimal cost effective designs.
Key to survival for many automotive firms will be the ability to bring sophisticated new powertrains to market in the shortest timescales. Unfortunately there is no single tool or toolset that can be used to design every powertrain from concept through to manufacture. This problem is compounded by the fact that manufacturers often have their own preferred proven component design tools and methods which are not available outside their own organisation.
Therefore, the industry faces an enormous challenge when it comes to using CAE tools with no easy solution and some clear issues that need to be addressed including the following:
- Product design must be right first time
- Holistic transmission/powertrain development is a must
- Efficient data exchange is required to allow collaborative working
Romax has a range of offerings aimed at improving the drivetrain concept design process and to facilitate collaboration right the way through the drivetrain development process:
RomaxDESIGNER is a simulation tool thatallows detailed analysis and optimisation of whole drivetrains.
CONCEPT brings rapid and intuitive modelling and analysis to the conceptual design phase of driveline development by enabling the early assessment of new design options by simultaneously considering a wide range of acceptance criteria using efficient analysis methods
CAD FUSION allows seamless data exchange between Romax products and third party CAD and gear design packages by incorporating advanced feature recognition and support for all common CAD formats
Dynamic FUSION extends the interoperability of models created in Romax products by creating dynamic models directly from CONCEPT and RomaxDESIGNER so third party multibody dynamics software can investigate and correct driveline dynamic problems.
In a typical design process, multiple models must be created from scratch and a specific model is required for each level of dynamic analysis. This can be time intensive, expensive and can lose much of the engineering intelligence of the design process. With the release CONCEPT, CAD FUSION and Dynamic FUSION, Romax Technology is actively looking to address some of the wider issues of driveline development. For manufacturers looking to lead the way in this area, efficient product development processes that emphasise the importance of a right first time approach and collaborative working will be essential. In order to do this effectively, engineering teams will need not only the right people and processes but also the right software tools.