Digital
Displacement® Automotive Transmission Publically Launched
Edinburgh, Monday, 4th April 2005 - Artemis Intelligent Power
Ltd has been developing an efficient automotive Infinitely Variable
Transmission (IVT) using Digital Displacement® with their
automotive Tier-1 licensee, Dana Corporation. Dana believes that
Digital Displacement® is an enabling technology for practical
hydrostatic transmissions with regenerative braking. The HEDDAT,
or High Efficiency Digital Displacement Automotive Transmission,
promises to cut car emissions by up to 30%, and was demonstrated
to Transport and Scottish Secretary Alistair Darling and the press
in Edinburgh in early April.
"The search for more environmentally
friendly technology in the car industry presents real business opportunities
to research and development organisations to exploit this growing
demand. Artemis Intelligent Power is a good example of a Scottish
university spin-off company leading the way." Alistair Darling,
Transport and Scottish Secretary
Artemis Intelligent Power exhibits
radical hydraulic hybrid car
In the past two years Artemis has been
working with Dana, one of the world's largest automotive components
manufacturers, to build a hybrid car with a high-tech hydraulic
transmission. The programme has been supported by the Energy Saving
Trust, EST, under the New Vehicle Technology Programme, NVTF, funded
by the Department for Transport, DfT. The Artemis HEDDAT project
has just completed its first phase, embodied in an outwardly normal
diesel Ford Focus. Under the bonnet, however, this is anything but
a standard car. The wheels are completely disconnected from the
engine, instead driven by high-pressure oil. As the car accelerates,
the engine is controlled to run at the optimum speed for the instantaneous
power being demanded of it. The fully developed car will also use
its energy-storage gas-accumulator to capture and recycle braking
energy. When this is charged, the car will be able to move off without
the engine, allowing it to be turned off to save fuel when the vehicle
is stationary. The projected fuel economy gain from all of these
features will be above 30% in a production vehicle. Hydraulic, or
hydrostatic, transmissions are currently used in off-road machines,
such as excavators and combine-harvesters, but have so far proved
too inefficient to spread beyond this limited niche. The Artemis
transmission uses new hydraulic components, developed and patented
by Artemis over the past ten years, which have unparalleled efficiency.
The Artemis machines maintain their high efficiency
over their whole operating range, making them suitable for use in
cars, where efficiency is very important. The computer control and
ultra-fast response of the Artemis hydraulic machines provides very
good driveability as well. Hydraulic drive has the environmental
benefits of an electric hybrid, but with some distinct advantages.
A transmission using Artemis technology is about a third the size
and weight of a similar electric hybrid transmission. And by storing
captured braking energy in a hydraulic accumulator instead of a
battery, full power is available instantly, even with the engine
off. A costly secondary storage device, an ultra-capacitor, is needed
to work around this in an electric hybrid. Hydraulic systems also
scale up to larger sizes well, and it is reasonable to expect that
the Artemis technology will one day be seen in trucks, buses, and
even non-electrified railway locomotives. Artemis is already planning
next phase in the project, replacing the remaining conventional
hydraulic components with ones designed and built by Artemis. This
will result in a further improvement in fuel economy along with
functional gains such as improved driveability and reduced noise.
"Most of the time when you're driving
you use less than ten percent of the available power.
Conventional hydraulic machines are no good at fifty percent,
let alone ten percent."
