Designing the electric vehicle of the future
Electric vehicles (EVs) are becoming increasingly important in the global effort to achieve climate neutrality. Reducing the number of fossil fuel-powered vehicles on the road – and improving EV efficiencies – can help to lower carbon emissions. What’s more, affordable pricing, along with technological breakthroughs, have made EVs an increasingly attractive and viable option for many consumers.
Improving the performance of EVs
Nonetheless, the widespread adoption of EVs has been hindered by consumer hesitancy, as well as various technological challenges. These technical issues have often been linked to vehicle performance, motion dynamics and braking strategy. The ACHILES project was developed to address these challenges – and make EVs ever more market viable. “The ACHILES project focused on enhancing an existing vehicle, the Audi Q2, by defining the architecture and control strategy for different subsystems,” explains project coordinator Omar Hegazy, a professor at the Vrije Universiteit Brussel (VUB) in Belgium. “These subsystems included the brakes, chassis, battery and powertrain, with newly developed e-motors.”
Technological breakthroughs achieved
The project team developed and prototyped innovative new components for each of these subsystems. These innovations were then integrated, and tested on an ACHILES vehicle. Important results were achieved in improving all four subsystems. “Each of these technological breakthroughs is a paradigm shift on its own, but together, they can significantly reduce the weight, system complexity and cost of an EV,” says Hegazy. “We were also able to show how they can increase reliability and user comfort, as well as safety and security.” The first innovation is a new torque vectoring algorithm that significantly improves vehicle dynamics. Overall stability was increased by more than 10 % through better steering. “The second innovation is a new wheel concept design equipped with full by-wire braking,” explains Hegazy. “This includes a new friction brake concept.” Tests showed that brake particle emissions could be reduced by at least 50 % by using the aluminium metal matrix composite disc installed in the ACHILES vehicle. The aluminium friction brakes also resulted in an overall weight reduction of around 19 kg. “The third innovation is an out-of-phase control, which intentionally dissipates excess braking energy in case of fully charged batteries,” adds Hegazy. “This also helps to reduce the weight of the brake system. The newly developed e-motor also enables high heat dissipation.” Finally, the fourth innovation is a centralised computer platform that hosts e-drive functionalities. This reduces the number of electronic control units and networks, and meets all necessary safety and security requirements. “This can support centralised domain controllers required to implement high automation and autonomy concepts, a key requirement for smart mobility,” notes Hegazy. “This can reduce the weight of the control system by up to 20 %.”
Inspiring future EV research
Hegazy and his team hope that the integration of all four ACHILES concepts into an EV will eventually help to reduce the total cost of ownership, increase the driving range and improve user acceptance and market uptake. “Moving forward, we would like to see all four technological breakthroughs further refined and optimised for mass production,” he concludes. “And second, we hope that the ACHILES project can inspire and guide future research and development efforts aimed at improving the performance, efficiency and safety of EVs.”
Keywords
ACHILES, EV, electric vehicle, carbon, emissions, brakes, chassis, powertrain