Design and Development of Semi Active MR Damper

Project Title

Design and Development of Semi Active MR Damper

Project Area of Specialization Mechatronics EngineeringProject Summary

Magneto-rheology is a category of Rheology that is concerned with the flow characteristics and continuous distortion of the materials under the presence of a magnetic field. Magnetorheological (MR) Fluid is a type of smart fluid which in presence of magnetic field varies its apparent viscosity  It is basically comprised of an oil base (carrier fluid) with suspended ferromagnetic particles (magnetically soft), ranging in micrometers (2 ?m – 20 ?m). This fluid can be used in various application where dynamic range of properties is required. Vibrations dampers are the best example for MR fluid application . A sponge type vibration damper that uses MR fluid to dampen vibration as a result of its variable viscosityis created.Controllable damping by designing an optimal magnetic circuit with a very small amount of current usually less than 1A is achieved using least amount of MR Fluid. Magnetic circuit is designed to provide enough magnetic field to create suitable shear rate for the damper to work. For this purpose using given design parameters and constraints an FEM model of the piston is designed using  software tools and then the design parameters are optimized to get better results.

Project Objectives

The objective of this study is to develop MR fluid Sponge dampers, and using FEM method to analyze a change in magnetic field density and hence optimizing the design parameters.

• To design a Semi-Active vibration damper (Use of Sponge type material to conserve MR Fluid)
• Using FEA tools to simulate and optimize the magnetic circuit in order to obtain required damping force.
• To fabricate a working model of the damper.

Project Implementation Method

• Literature Review
• Designing of Semi-Active Damper System using Creo parametric 5.0/Solidworks
• Analysis using COMSOL Multiphysics (FEM)
• Fabrication of prototype.
• Testing of prototype.
• Thesis

Benefits of the Project

Benefits of sponge type MR Damper over other dampers are as follows:

• Sponge type MR Dampers do not require additional components which are a must in other design variations for instance seals, lids, valves etc.
• There is no fear of Ferro fluid /MR fluid leaking from the casing as the foam soaks all the fluid.
• The components required to construct a sponge type MR damper are easily available and relatively low-priced and require low alteration. For example creation of an electromagnet within the piston casing
• Hassle free installation and arguably maintenance free
• Due to its small size, it can be fitted in any position
• Low power requirement for functioning (semi-active), less than 1 A current is enough to generate more than 200N force
• Due to low weight and small size of sponge type MR Damper with additional advantage of direct shear mode the response time is fast when compared to other modes and types.
• Heat generated as result of damping out excessive vibrations and as a result of rubbing of MR soaked sponge and cylinder casing doesn’t impact the overall working and can be dissipated into surrounding air.
• Independent nature of MR (Ferro fluid) with reference to high temperature ensures low maintenance.
• The perforated sponge due to its absorbent nature retains Magnetorheological fluid (Ferro fluid) and hence no filling of fluid is required.
• The semi-active vibration damper system could replace the conventional dampers used in automobile industry/ manufacturing industry/ production industry etc.
• It could be used in suspension systems of space vehicles
• Semi active dampers can even operate during power failures.
• It could provide better damping of vibration during critical conditions like rocket launch.
• Semi active dampers could sufficiently reduce the damage to the building during earthquakes.

Technical Details of Final Deliverable

Semi-Active damper system – uses Magneto-Rheological Fluid (MRF) 132-DG (250 ml).

Specifications – Prototype of the semi-active damper that contains the piston and cylinder assembly with required amount of MR fluid.

Simulation Results – COMSOL Multiphysics Analysis (FEM)

Final Deliverable of the Project Hardware SystemCore Industry ManufacturingOther IndustriesCore Technology OthersOther Technologies RoboticsSustainable Development Goals Industry, Innovation and InfrastructureRequired Resources

Item Name	Type	No. of Units	Per Unit Cost (in Rs)	Total (in Rs)
			Total in (Rs)	78000
Mild Steel Channels/Pipes	Equipment	8	1000	8000
Magneto-Rheological Fluid (MRF) 132-DG (250 ml)	Equipment	1	60000	60000
Different costs	Miscellaneous	2	5000	10000