Electric Impulse Charging
Siemens VDO has released details on a new supercharging concept.
Electric impulse charging is accomplished by installing an
electromagnetically-controlled valve in the intake manifold ahead of each
cylinder. As the piston travels downward during the intake stroke of the
combustion process, the valve is closed, creating a vacuum by sealing the
cylinder. Just before the piston reverses direction to begin the compression
stroke, the valve opens and the pressure drop that has been created draws air in
at the speed of sound. The sharp intake of air bounces off the piston crown
creating a counter-wave flowing back toward the top of the cylinder.
The valve seals again before the high-pressure wave can escape, resulting in
an increased volume of air in the cylinder. As the valve switches from open to
closed in a few milliseconds, this charging effect becomes immediately available
within one power stroke.
With the electric impulse charger up to 30 percent increase of torque is
possible at low rpm.
An additional benefit of employing electric impulse charging solution is the
increased air pressure in the cylinder at the end of the combustion process
improves the purging of exhaust gases. Far less residual gas is carried over
into the intake and compression strokes of the next working cycle, which reduces
the combustion chamber temperature and the tendency of the engine to knock.
Delphi Active Front Steer
Delphi Active Front Steer helps provides drivers with simplified city driving
and parking by reducing the turning required at low speeds so that a
hand-over-hand parking manoeuvres can be accomplished in as little as two thirds
of a turn of the steering wheel. Delphi AFS smoothly transitions from a
low-speed steering ratio to a high-speed steering ratio, providing a tighter,
sportier feel for driving enjoyment and better control on the highway.
AFS accomplishes this by modifying the steering kinematics, or motion, of the
vehicle in a manner similar to steer-by-wire. The system electronically
influences the steering angle on the wheels enabling it to be greater or less
than the driver’s steering wheel angle input. Turning into a parking spot or
even manoeuvring a hairpin turn at moderate speeds can be accomplished with
significantly fewer turns of the steering wheel. In essence, the system
electronically turns the road wheels at a rate different than the rate the
driver turns the steering wheel. Although some may think this could be intrusive
or controlling, those that have experienced Delphi AFS suggest it helps make
driving very easy and enjoyable with a very natural, transparent feel.
Unlike steer-by-wire, AFS maintains the mechanical link and uses the existing
electrical architecture. This mechanical link helps ensure system safety. If the
system is switched off or inadvertently loses power, Delphi AFS engineers
incorporated a smooth default to the base steering ratio, apparently without
disturbing or alarming the driver.
Delphi Active Front Steering can be integrated with controlled braking to
provide a more effective vehicle system solution to stability control than
brakes alone. AFS instantaneously delivers steering control; counter steering
(ie opposite lock steering) the vehicle to bring it back on its intended course
and if needed, blending in braking. In addition, this integration can help
minimize vehicle-stopping distances on split and mixed frictional coefficient surfaces
while maintaining directional stability.
Delphi Active Rear Steer
Not content with Active Front Steer, Delphi is also
exploring the use of rear-wheel steering, a technology exploited to some degree
by the Japanese in the mid-Eighties. However, the use of ‘active’ technologies
adds potentially much more effectiveness to the systems. The demo car that the
company is using is a Jaguar S-type.
The system is a low angle rear wheel steering system, which is specifically
designed to offer European vehicle manufacturers an innovative, affordable
solution for dynamic handling enhancement and active safety management on
Active Rear Steering can serve as a primary mechanism for enhancing the
vehicle’s handling performance by using its highly tuneable software. Using
dynamic control algorithms, the system provides the ability to specifically
“dial in” desired handling characteristics. For instance, if the desired vehicle
character is for a smoother ride via a softer suspension, Active Rear Steering
can be used to help regain the desired handling using an algorithm that
dynamically adjusts the rear wheel angle according to a vehicle behaviour model.
The result is optimized handling performance and ride comfort.
“Active Rear Steering separates
the yaw and lateral dynamics of the vehicle,” explains Dr. Jean Botti, chief
Delphi Dynamics &
“This gives chassis design and tuning experts a new degree of freedom to control
vehicle motion. When combined with the latest in advanced algorithms, Active
Rear Steering allows our customers to achieve superior handling performance
while also increasing dynamic safety through active rear steering.”
Delphi Active Rear Steering helps minimize over steer and under steer at all
speeds, and on virtually all surfaces, even during normal driving, without
slowing the vehicle. Emergency lane changes, or elk test manoeuvres, become more
predictable, more manageable and less stressful when rear steering is added to
the equation. Active Rear Steering can be integrated with controlled braking to
provide a more effective vehicle system solution to stability control than
brakes alone. Together these systems help deliver instantaneous rear steering
control to bring a vehicle back on its intended course and blended braking as
needed. This approach minimizes any slowing of the vehicle making the correction
less intrusive to the driver. In addition, by allowing steering to maintain
directional control and braking to slow the vehicle, this integration can help
reduce vehicle-stopping distances on split and mixed frictional coefficient surfaces, such
as snow and ice, in a stable, controlled manner.
“Active Rear Steering complements and expands the impact of brake-based
stability control systems on vehicle dynamics by improving handling and yaw
stability,” states Botti. “Bringing steering into the equation allows our
customers to deliver the ultimate in active safety combined with a comfortable
ride and superior handling.”
The system can also be configured with unique algorithms for improved
handling and safety while towing a caravan or trailer.
DaimlerChrysler’s F 500 MIND Research
F 500 Mind, DaimlerChrysler’s new research vehicle, is packed with
innovations. “Mind” stands for intelligence and expresses the wide variety of
For the F 500 project the engineers at DaimlerChrysler developed a hybrid
engine - a 4-litre, V8 diesel engine with 184kW and an electric motor with 50kW.
The potential fuel savings, as
defined by the New European Driving Cycle (NEDC), are up to 20 percent higher
than those associated with comparable conventional drives. About 10 percent can
be attributed to the electric motor, while about six percent is the result of
regeneration — in other words, the recovery of kinetic energy. This energy is
converted into electricity when the brakes are applied and is stored in a new
type of lithium-ion battery.
People who open the driver’s door in the F 500 Mind shouldn’t
be alarmed when they see the steering wheel move to the side. In fact, the wheel
actually slides 14 centimetres toward the vehicle’s middle to enable the driver
to easily get in and get out. The movements are possible because the designers
have abandoned the use of a continuous mechanical steering column. In its place,
the F 500 has a drive-by-wire steering system in which the steering movements
are transmitted as electronic commands, rather than via mechanical systems. The
steering wheel and the steering gear are connected with each other only through
cable and data.
To ensure that the connection is as secure as a mechanical one, all of
the various components are at least duplicated and in some cases are even
present fourfold to provide redundancy.
The F 500 also has a new type of mechatronic steering wheel that creates the
normal mechanical resistance when the wheel is turned and prevents drivers from
thinking that they are holding a non-working part in their hands. In this
system, a mechanical spring and an electric motor produce resistance based on
the driving situation and create the normal “steering sensation.” The steering
gear is also new in the drive-by-wire concept. Because the F 500 has a driving
mode with purely electrical propulsion, the design engineers replaced the normal
hydraulic steering control element with an electric steering rack.
Electronics also have found a place in the floor: Instead of
the conventional pedals that are depressed, the F 500 Mind has “force-sensitive”
pedals. These are installed in a flat plate and contain pressure sensors that
electronically transmit the driver’s commands to the throttle valve or braking
system when he or she steps on the accelerator or the brakes.
The benefits of the system can be seen in the interior and front-end
structure. In the footwell, the electronic pedals create about 12 centimetres of
additional space — space that is normally taken up by the mechanical pedal
travel. In an ergonomic payoff, the pedal unit can be adjusted to suit the
driver’s leg length because the only thing that has to be moved is cable; there
is no requirement to adjust mechanical parts.
One of the most exciting new innovations in the F 500 is “multivision.”
This totally new type of multifunctional display installed in the dashboard
provides the driver with an array of information such as vehicle speed, the
driving mode and the navigation system’s road map upon request.
When the car begins to move, “multivision” appears as a high-quality
instrument cluster with three round analog displays: the tachometer to the
right, the speedometer in the middle and the display for the hybrid power plant
to the left. Needles are illuminated and borders can be dimmed.
At the press of a button, the hybrid display becomes an
operator menu with which the driver can do such things as set up the cruise
control or a trip computer. Information from the assistance systems also can be
displayed. The menu is operated using buttons inset in the steering wheel. In
the same way, the driver can switch off the tachometer display and replace it
with that of the navigation system.
And for trips made in twilight or at night, the F 500 has one other special
feature that raises the safety level. “Instead of the navigation system,” a
DaimlerChrysler spokesman says, “the video image of the night-vision system,
which works in the infrared range, can be displayed. In this manner, a driver
can considerably expand his or her field of vision in situations where
visibility is poor.”
Using the night-vision system developed by DaimlerChrysler research, the
driver can not only follow the course of the road, but also recognize obstacles,
pedestrians and cyclists at a distance of 150 metres. Normal low-beam lighting,
by contrast, is good for only 40 metres.
Passive night-vision systems recognize only those objects
that give off warmth. However, that’s no problem for the system in the F 500,
which has its own source of light. Two lasers integrated into the headlights
send out invisible infrared light. An infrared video camera installed behind the
windshield records the reflected image and supplies a black-and-white video for
the “multivision” display.
For the driver’s seat, the F 500 offers the “cone of sound,” another piece of
pace-setting technology. The system, which is based on ultrasonic technology,
employs special speakers that transmit the sound at a very sharp angle.
In this way, they can provide information that is heard only by the
driver. Such information includes traffic reports, telephone calls, warnings and
language-operation dialogues for the navigation systems or radio. The benefits
of this pinpoint speaker system are obvious - the other people in the car don’t
have to listen to traffic reports or listen in on the driver’s telephone
In the F 500, the driver’s seat is the only location outfitted with this
innovative audio technology. However, the researchers plan to employ the
knowledge they gain from their experience to further refine the system. When it
becomes available for all seats at some point down the research road, each
occupant will be able to select his or her own music without disturbing the
other people in the car.