Examples of MR Devices and Systems

MR fluids have been used commercially since the mid-1990s. The first application was a small controllable MR fluid brake in aerobic exercise equipment 

The MR fluid-based suspension systems implemented on these various vehicles enable simultaneous ride comfort control and body motion control. As indicated in Fig. 6.85, the control system architecture for these systems processes inputs from relative position sensors at each wheel. In addition, inputs from a lateral accelerometer, yaw rate sensor, steering angle sensor and speed sensor all feed by way of a CAN BUS into the controller. The control algorithms are quite complex and seek to simultaneously optimize a wide range of performance features including overall handling, overall ride comfort, body control, road noise, head toss and a subjective safe feeling. 

In another civil engineering application, MR fluid dampers have been used to mitigate potentially damaging wind-induced cable vibrations in a cable- 

As a final example of a MR fluid controlled adaptronic system, the smart prosthesis knee developed by Biedermann Motech GmbH [178-181] is presented. This system shown in Fig. 6.91 is a complete artificial knee that automatically adapts and responds in real-time to changing conditions to provide the most natural gait possible for above-knee amputees. The heart of this system is a small magnetorheological fluid damper that is used to semi-actively control the motion of the knee based on inputs from a group 

Real- time clock Work and program memories 

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