1893 Gainsborough Dr., Atlanta, GA 30341        dick@magneshocks.com         Phone: 770-377-6430
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How It Works  &  Technical Info
Magneshocks System Overview (PDF file)
How does M-R fluid work?
The M-R fluid is basically composed of micron size particles of iron suspended in an oil base.
In the presence of a magnetic field, these iron particles want to form chains & stick together.
The stronger the field - the stronger these chains become. To move the fluid you need to break the chains.
The apparent viscosity of the M-R fluid changes, which changes the damping force of the shock.
This action is essentially instantaneous - it happens as fast as the magnetic field can be changed.
The piston contains an electromagnet, and an annular orifice(2), through which the M-R fluid passes.
The controller varies the current to the electromagnet (to change the magnetic field’s strength) and the damping force (which is basically resistance to flow) varies proportionally.
AMRDS™ =  Active 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 hydraulic oil.
M-R fluid will change viscosity (get thicker) in the presence of a magnetic field.

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", sense every motion of the chassis & suspension and adjust EACH shock for OPTIMUM damping force 1000 times per second.
Low power requirement: Avg. <1A, Max. 3A (on 12V vehicle).
Simple Installation:
1) Simply “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 Controller box,
4) And, another to the ignition switch.….. It’s Done!
Suspension “bottoming” & “banging” is nearly eliminated.
Peak loads on all chassis components are greatly 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.
With REGULAR Shocks:

A soft shock controls the wheel - it rides well & handles terrible!
A stiff shock controls the chassis - it handles well & rides terrible!
A serious compromise must be made: Take your choice - one or the other!
Regular shocks have no way of knowing if the wheel is moving or the chassis, or both.
Also, each shock works independently - it has “no idea” what the others are doing.
So, shocks can’t differentiate normal movements from roll, pitch, dive, squat, heave or yaw!
And, they certainly cannot detect cornering, braking or acceleration forces.
So, ride engineers MUST choose something in between - neither one is optimal.
It is simply IMPOSSIBLE to get a car that Rides Well & Handles Well.  
You get one OR the other OR both in between.
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 cornering, braking and acceleration forces.
It also knows if any wheel in the suspension system is about to bottom-out or top-out.
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 - at the same time - 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.
With MagneShocks™ you don't have to compromise between best ride & best handling!
System Features:
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).
An 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 conditions.
All connectors use gold-plated contacts. Water resistant is standard.
Control Algorithms:
The basic control scheme of AMRDS is:
Use the shocks’ damping to minimize any up or down movement of the chassis.
Prevent suspension bottoming out or topping out.
Keep the chassis level, even when braking, accelerating or cornering.
Sense the vehicle’s load and modify the control algorithms automatically.

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 & life-cycle-costs.

MOST important: AMRDS looks at the entire vehicle and operates as a “system”.

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 actions.
AMRDS can also be configured, through software; to detect and automatically compensate
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 arrive refreshed
(motion sickness is virtually eliminated), ready to go.
Shock Design:
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 Vehicles:
48mm (1.89”) for light vehicles.
60mm (2.40”) for medium vehicles.
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 requirements.
For best performance and life, we usually recommend eyerings with teflon-lined spherical bearings, wherever practical.
Number of tires/wheels:
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.
Electronic Options:
An external “switch” for driver selectable “ride” can be provided.
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:
interface to CANbus (J-1939 etc.);
provide system status LEDS and/or other I/O;
provide selectable ride/handling algorithms change;
provide a serial port for data or sensor I/O;
interface to other sensors (speedometer, steering or throttle position, etc.);
provide a port for in-field software upgrades, system analysis etc.
We can even develop “Rollover Early Warning Systems”. The sensors and processors already exist.
Damping Range:
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 Fig.1.

If the “off” damping is raised the “on” goes up too. The ratio (“ON” vs “OFF”) remains about the same. All values are proportionally higher.

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).
The actual Damping Range, from Softest to Stiffest can be just about anything desired.
There are 2 examples here: 
Example #1 one is the most common for most cars - ranging from 20 to 220 at Zero velocity.
But, sometimes we need stiffer dampong  - often because of leverages in the suspension.
Example #2 would be twice as stiff at any velocity or setting (40 to 440 at Zero velocity).
The practical limits are 10 to 100 as lowest and highest at 300 to 3000 at Zero velocity.

MagneShock™ designs, tests, and manufactures active damping
suspension systems using Magneto-Rheological (MR) technology.
Contact us today to improve your product.
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MagneShocks AMRDS Know Everything!
There are NO Compromises - you get the best of BOTH Worlds
The additional 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 called for as a function of ANY variable, calculation or sensor signal.
The actual damping is infinitely adjustable in between these two limits.
Note that a MagneShock can develop significant damping at ZERO velocity.
This means it can be “locked-up” - NO motion will occur until this large force, applied to the damper, is exceeded.
Dampers covered under US Patents 6,543,589 and 5,277,281 and 4,877,699 and 5,878,851 and 6,095,48