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CONCLUSIONS

A magnetorheological fluid has been specially developed and incorporated into a damper prototype
also specially used for this purpose. A set up with a designed load cell was used independent and also
was mounted in an Autograph Shimadzu system in order to determine the force, velocity and
displacements at different forces. The constitutive model is given by a mathematical power expression
constituted by two polynomial expressions, which are in function of the electrical current. The
suspension system is taken from a real model actually in use for a commercial automobile
characterized by its design and excellent performance. The simulated system shown the movements
and quantify the forces and displacements. The results obtained from a comparative analysis shown
strong differences between passive and semi-active suspension system. From the experiments and
simulations done, it has been shown that; the characterization of a damper can be made through of the
physical characteristics of the MR fluids, current, damper design and spring characteristics. In addition
it has been shown that the use of ADAMS software is an excellent computational tool to simulate
dynamic mechatronics systems. Finally a reconfigurable suspension system has been analyzed. Its
ability to change its rheological properties in addition to its quickly response to the circumstances
makes the MR technology a feasible way to develop other reconfigurable systems. Future work
involves the introduction of a couple systems in the simulator in order to reproduce real events for
driving, to determine the details of mechatronics control and to improve the coil's design for its
implementation in a complete prototype. A control algorithm is necessary to be developed and
implemented, so that, the system responds according to the road conditions and the comfort required
by the human being.

NOMENCLATURE

Ampere / Force required to overcome damper
a Power equation constant resistance
b Power equation exponential constant i Current through the coil
c Equivalent damping coefficient MR Magnetorheological
cP Centipoises m Meter
DC Direct Current s Seconds
EDC MR Equivalent Damping Coefficient N Newton
8 Damper displacement or deformation X Piston rod velocity
F Force exerted by the damper

REFERENCES

Bossis, G. (2002). Magnetorheological Fluid. Journal of Magnetism and Magnetic Materials. 252.
224-228.
Cochin Ira and HJ. Plass. (1990). Analysis and design of dynamic systems, Harper Collins, New York,
NY.
El Wahed Ali, K. (2002). Electrorheological an Magnetorheological Fluids in Blast Resist Design
Applications. Materials & Design, 23. 391-404.
Nakamura, Taro. 2004. Variable Viscous Control Of A Homogeneous ER Fluid Device Considering
Its Dynamic Characteristics Mechatronics 14. 55-68.
Ozdalyan, B., Blundell M.V. (1998). Anti-Lock Braking System Simulation and Modeling in
ADAMS. International Conference on Simulation. 140-144.
Yao, G.Z. (2002) MR Damper and its Application for Semi-Active Control of Vehicle Suspension
System. Mechatronics 12. 963-973.