Magneto-Rheological Damping System)
(using Magneto-Rheological fluid technology)
(1) AMRDS™ is an
"intelligent" shock absorber (damper) system,
mfd. by MagneShock Div., Arre Industries Inc, of Atlanta, GA.The dampers use Magneto-Rheological (M-R) fluid instead of
M-R fluid will change viscosity (get thicker) in the presence of a
Each MagneShock™ contains an electromagnet inside the piston.
Current to the electromagnet instantly controls the viscosity of the
fluid thus instantly controlling the damping force.
Integrated sensors & solid state electronics "read the road",
motion of the chassis & suspension and adjust EACH shock
damping force 1000 times per second.
Low power requirement:
Avg. <1A, Max. 3A (on 12V vehicle).
1) “Bolt-On” the shocks into the existing mountings),
2) Mount the controller box (approx. 7”x10”x2-1/2”),
3) String a cable from each shock to the box,
4) And, another to the ignition switch.….. It’s Done.
Suspension “bottoming” &
“banging” is nearly eliminated.
Peak loads on all chassis components are reduced.
Result: Life-cycle-costs reduced considerably if used off-road.
A MagneShock AMRDS
system can be designed for YOUR vehicle – NOW.
Dampers are covered under US Patents
6,543,589; 5,277,281; 4,877,699; and 6,095,486.
A soft shock
controls the wheel – it rides well & handles terrible!
A stiff shock controls the chassis – it handles well & rides
A serious compromise
must be made: Take your choice – one or the other!
Also, each shock works
independently - it has “no idea” what the others are doing.
Shocks can’t differentiate normal movements from roll, pitch, dive,
squat, heave or yaw!
And, they certainly cannot detect cornering forces.
engineers choose something in between – neither one is optimal
MagneShocks Know Everything!
The sensors tell the
controller exactly what each corner of the chassis is doing (in
all 3 directions) and exactly what each wheel is doing too.
The controller can
detect roll, pitch, dive, squat, heave & yaw as well as
It also knows if the suspension system is about to bottom-out or
It takes ALL this data,
decides how much damping each shock should have, at EACH instant,
for the BEST ride, the SAFEST & most STABLE handling and to prevent
the suspension from running out of travel. It acts instantaneously
to control all these motions & forces - updating each shock 1000
times per second.
When it needs to be soft – it’s soft.
When it needs to be stiff – it’s stiff.
MagneShocks™ you don't have to compromise
between best ride & best handling!
Reaction time is very fast (usually <0.002 seconds) –
much faster than ANY other technology.
||High strength aluminum
alloys are employed for faster heat dissipation, lower
operating temperatures, which improve performance and
reliability. (a damper’s “job” is to convert mechanical
energy into heat).
AMRDS system usually weighs no more than the one it replaces
– even counting the controller & cables. The MagneShock
Controller can compensate for M-R fluid viscosity
variations. AMRDS can be designed for use in sub-zero
All connectors use
gold-plated contacts. Water resistant is standard.
The basic control scheme of AMRDS is:
Use the shocks’ damping to minimize any up or down movement of the
Prevent suspension bottoming out or topping out.
Keep the chassis level, even when braking, accelerating or
Sense the vehicle’s load and modify the control algorithms
Schematic of MagneShock AMRDS system.
|For example, we know that the ride will become very bad when the
suspension bottoms out
(this is what destroys suspension systems & costs the big money).
So, AMRD stiffens the
damping as it nears the end of its travel to prevent the “bang”.
This makes the ride a bit worse
NOW but much better LATER (because it doesn’t crash against the
stops).This saves our customers a lot of money on reduced maintenance &
MOST important: AMRDS looks at the entire vehicle and operates as a
It also “knows” if the vehicle is rolling, pitching, diving,
squatting, heaving or yawing and will
adjust ALL of the shocks simultaneously to best control these
AMRDS can also be configured, through software; to detect and
for variable loads (as a function of varying ride height or,
pressure in your suspension system).
Durability & Maintenance:
A suspension system with AMRDS is far less likely to crash against
its travel limits.
So, peak loads and accelerations are substantially reduced
throughout the entire vehicle.
Suspension and chassis components show less fatigue.
This equates to a more durable & reliable vehicle - to increased
life and decreased
maintenance & life cycle costs. Most Important: Vehicle occupants
(motion sickness is virtually eliminated), ready to go.
We will design and manufacture whatever you need.
MagneShocks are of Aluminum body, Mono-tube, Gas Pressurized
design – the most technologically advanced & reliable.
At present, we
have developed two (2) basic bore sizes of MagneShocks for
These units can
be made in any stroke length and with any mounting ends your
application requires. Several rod sizes and body OD
configurations are available according to actual application
performance and life, we usually recommend eyerings with
teflon-lined spherical bearings, wherever practical.
The AMRDS controller, at present, handles from 1 to 4 wheels.
Controller adaptability allows for
future systems of 6, 8 or more. These will be made available as
required by customers in the future.
An external “switch” for driver selectable “ride” can be
It can be “hard-wired”, or operate through the CANbus, to
call up different control schemes
such as: “stock shock emulation”, “smoothest possible ride”
or “best possible handling”.
If you desire
more connectability we can:
CANbus (J-1939 etc.);
system status LEDS and/or other I/O;
selectable ride/handling algorithms change;
serial port for data or sensor I/O;
other sensors (speedometer, steering or throttle
port for in-field software upgrades, system analysis
We can even
develop “Rollover Early Warning Systems”.
The sensors and processors already exist.
MagneShocks have an exceptionally broad damping range (the
difference between lowest &
highest damping values). The overall range is designed for
the needs of each vehicle.
The shock’s damping shown in Fig.2 is twice as stiff as
If the “off” damping is raised the “on” goes up too. The
ratio (“ON” VS “OFF”) remains about the same. All values are
In the “current off” configuration the M-R fluid is at its
lowest viscosity and the damper has its softest damping with
a substantially linear force-velocity damping curve (Minimum
is OFF in Figs.1 & 2).
When “current on” is applied to the electromagnetic circuit,
the M-R fluid’s viscosity increases in proportion to the
magnetic field strength, which increases the damping force
(Maximum is ON in Figs.1 & 2).
damping (from turning on the “M-R”) is nearly constant at
any piston velocity. However, the ratio between highest &
lowest possible damping force is usually 10:1 or better at
low piston speeds (around 1 in/sec).
Any damping force in between these two lines (the GREY
areas) is instantly available in a MagneShock.
This additional damping can be a function of ANY variable,
calculation or sensor signal.
The actual damping is infinitely adjustable in between these
Note that a MagneShock can develop significant damping at
This means it can be “locked-up” - NO motion will occur
until this large force, applied to the damper, is exceeded.