2012 Toyota FT-Bh Concept - Hybrid of the Future
2012 Toyota FT-Bh Concept is making its debut at the 2012 Geneva Motor Show and will showcase its ultra-light body, weighing less than 800kg. This demonstrates what can be achieved in terms of fuel consumption and CO2 emissions in an affordable family supermini. Due to the exclusive low weight, the aerodynamic design and the highly efficient powertrain, the FT-Bh Concept can achieve average 134.5mpg fuel consumption and 49g/km CO2 emissions. Toyota's aim was to achieve the best possible fuel economy and emissions. This was made through five key areas: reducing weight; driving resistance (including aerodynamic and tyre performance); powertrain efficiency; thermal energy management; and electricity savings.
Under the slogan "Ecomotion" went the work of the styling of the new FT-Bh, with its shape demonstrating a new approach to bodywork design. Key panels, such as the roof, are formed to represent the way fabric can be stretched taut between fastening points, to reflect their ultra-light weight. The front end of the car broadcasts Toyota's current design philosophy. The ultra-slim A and C-pillars maximize the visibility and the sense of space in the cabin. The best possible aerodynamic performance and the drag coefficient of just 0.235, is possible thank to the uplifted rear bumper and chevron-shaped corner elements. The stretched fabric-look carries through to the minimalist interior, with a concave centre console creating a driver-focused cockpit.
The aim for the concept vehicle was to achieve 25 per cent saving on the 1.0-litre Yaris's 1,030kg weight. Thank to the combination of high-tensile steel, aluminium and magnesium in the construction this lead to the weight of just 786kg. Although the hybrid powertrain is heavier than the three-cylinder 1.0-litre engine (weighing about 60kg), the combined mass of the bodyshell was further reduced. For instance the interior trim, chassis and electronics had to be reduced by around 340kg. These large saving in the weight of cabin parts has had a ripple effect in weight reduction in the rest of the vehicle, which allows the components to be downsized. And less weight means a smaller displacement engine can be used, further saving weight and thermal energy losses.
FT-Bh's full hybrid drive system is a masterpiece in terms of powertrain downsizing. With substantial weight savings in every driveline component, it is almost 90kg lighter than theHybrid Synergy Drivesystem used in today's Prius for example. The engine is lightweight, namely: two-cylinder 1.0-litre Atkinson cycle petrol engine. It allows the combination of high efficiency with low thermal capacity and benefits with detailed measures to increase combustion efficiency and reduce friction. The result is fuel consumption of 134.5mpg and CO2 emissions of just 49g/km.
Further benefits from the car's light weight is that it makes the vehicle agile and responsive to throttle and brakes, and thanks to its electric motor delivering maximum torque from standstill, it is nimble, too. In addition, the Toyota's Hybrid Synergy Drivetechnology serves as a study for how even greater fuel efficiency might be achieved in the medium term by using two alternative powertrains: a compressed natural gas hybrid (CNG-HV), with 38g/km CO2 emissions; and a Plug-in hybrid (PHEV), emitting just 19g/km.
What is interesting here is that the concept represents a comprehensive study in next-generation aerodynamic techniques. For instance it features air curtain intakes on the frontal extremities of the bodywork; air-stream alloy wheels; the replacement of airflow-disrupting door mirrors with cameras; latches in place of handles to open the doors; a pagoda-style roof with a dropped rear section; and a sharply cut rear end that incorporates an air outlet slit and an underfloor spoiler to smooth the flow of air away from the vehicle. Together these measures bring the Cd down from a B-segment/supermini average of about 0.29 to just 0.235. Toyota FT-Bh has large diameter 145/55R18 low rolling resistance tyres, which make a significant contribution to bringing down the road load and driving resistance, with no loss of grip or traction.
More highlights about the FT-Bh are concerning the improvements in the recovery of thermal energy and a 50 per cent reduction in electricity consumption. This was achieved through thermally efficient components in the cabin. In addition, the air conditioning focuses only on parts of the car where people are sitting. The amount of electricity used by the LED headlamps, interior lighting and other electrical components has been significantly reduced, to the extent that power consumption is half that of conventional cars. The glazing has been designed for maximum thermal efficiency and even the matte paint has been chosen for its excellent heat insulation characteristics.
Source: Toyota