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Honda Develops World's First Super Handling All-Wheel-Drive; Available this Fall in the Acura RL (North America) and the Legend (Japan)

Tokyo, Japan, Apr. 01, 2004 - (JCN Newswire) - Honda Motor Co., Ltd.
today announced the development of a new Super
Handling All-Wheel-Drive system, called SH-AWD, that provides cornering
performance that responds faithfully to driver input, and outstanding
vehicle stability. A world's first, the SH-AWD system combines
front-rear torque distribution control with independently regulated
torque distribution to the left and right rear wheels to freely
distribute the optimum amount of torque to all four wheels in accordance
with driving conditions. The new system will be available this fall in
the Acura RL (North America) and the Legend (Japan). 

By monitoring driver input and driving conditions, the SH-AWD system
determines the optimum front-rear and lateral (left-right) torque
distribution. This information is then conveyed to the rear
differential, where direct electromagnetic clutches continuously
regulate and vary front-rear torque distribution between ratios of 30:70
and 70:30, and lateral torque distribution in the rear wheels between
ratios of 100:0 and 0:100. Torque is used not only for propulsion, but
for cornering as well, resulting in a significant enhancement in vehicle

The SH-AWD system is composed of sensors to detect steering angle,
lateral g, and other vehicle information; an ECU; and the rear
differential. The direct electromagnetic clutches inside the rear
differential, another world's first, employ electromagnets to obtain
precise control over the multi-plate clutches. Built-in search coils
monitor the gaps between the electromagnets and the magnetic body to
achieve precise, continuously variable torque regulation. 

The rear differential is also equipped with a built-in acceleration
device, yet another worldfs first. During cornering, the track of the
outside rear wheel normally falls outside the average of the tracks of
the front wheels. The outside rear wheel does not rotate fast enough to
keep up with the front wheels, preventing efficient transmission of
torque. To counteract this problem, the SH-AWD acceleration device
alters the gearing to speed up the outside rear wheel's rotation
relative to the front wheels. This reduces torque transmission losses
and significantly improves vehicle maneuverability.

At Honda, driving pleasure is regarded as one of the most important
factors in vehicle development. The new SH-AWD system features
"feed-forward" control, which utilizes the degree of driver input to
determine appropriate torque distribution. This results in a
super-neutral steering feel that responds with optimal faithfulness to
the driver's handling of the steering wheel, realizing outstanding
driving comfort and stability.

About Honda Motor Co., Ltd.

Honda is one of today's leading manufacturers of
automobiles and power products and the largest manufacture of
motorcycles in the world. Honda has always sought to provide genuine
satisfaction to people worldwide. The result is more than 120
manufacturing facilities in 30 countries worldwide, producing a wide
range of products, including motorcycles, ATVs, generators, marine
engines, lawn and garden equipment and automobiles that bring the
company into contact with over 17 million customers annually.For further
information, please visit the Honda Motor Co., Ltd. home page at:> 

Honda Motor Co., Ltd.
Masaya Nagai