In this brief article, we will discuss in-depth, the working principle of the MagneRide shock absorber and the vehicles that feature MagneRide suspension.
What is the MagneRide suspension?
Magneride dampers feature a monotube damper filled with a damping fluid that comprises a special mineral oil that has metal infused, called Magneto-rheological (MR) Fluid. The speciality of MR Fluid is that it changes its viscosity in proportion to the Magnetic applied to it. The MR Damper’s damping settings are changed using Magnetic energy in an active way.
The need for MagneRide Shocks
Conventional Hydraulic Dampers work with the principle of valve restriction to the flow of hydraulic fluid motion within the damper. As the suspension moves, the shock upper piston-rod follows this motion. Because of the hydraulic arrangement, the hydraulic fluid is squeezed through the valve orifices to produce a resistance called ‘Damping Force’. Imagine the hypodermic syringe used in a hospital. You can feel the resistance of the plunger as you try to press it down harder. The resistance comes from the extremely small syringe orifice. The conventional hydraulic damper works in a similar fashion. The Piston of the damper is the plunger and it has small orifices, called piston valves, which are similar to the effect of the needle.
The damping rate or damping force is determined by the size of the orifice, the viscosity of the liquid, and the size of the piston. The bigger the orifice, the more easily damping fluid passes through the piston valve. Conventional dampers are designed such that as the piston moves faster, the resistance increases in the valves due to the mechanical design of the orifices. This means that it is possible to plot a curve characteristic of damping force versus velocity in bump as well as rebound.
So now here is the problem. With only one curve, it is possible to, at best, only tune the damper to what an average of road conditions would demand. The only better damper design is one in which there are multiple curves that can suit multiple conditions. This is where the Magneto-Rheological Damping concept becomes relevant.
Damping hydraulic fluid viscosity is an important influence on damping resistance. This is one variable that was always a constant with conventional dampers. In the case of Magneto-Rheological Dampers, the valve orifices are eliminated, and instead, the hydraulic fluid viscosity is varied. The advantages of employing this strategy are:
- The Magneto-rheological principle allows the fluid to change viscosity instantaneously (in milliseconds)
- The viscosity can be varied across a wide range of values in micro steps, thus giving a wide range of damper adjustability.
How does the MagneRide Shock absorber System work?
- Magnetic Ride Control Dampers, also called MagneRide, developed by Delphi Systems, was first launched in 2002 in the Cadillac Seville. The MagneRide is currently in its 4th generation of development and manufactured by the BWI Group
- The MagneRide is an Active Suspension system that uses wheel-motion sensors to continuously sense suspension movement and acceleration and instantaneously alter the damping rate of the shocks.
- In Contrast to the conventional hydraulic shock absorbers that force fluid through a series of internal valves, the MagneRide shock absorbers do not have any valves, rather the Magneride shock simply varies the amount of charge to the fluid inside the strut and vary its viscosity, and in turn, the damping.
- The basic principle of the MagneRide is that a thicker, or more viscous, damping fluid would offer more resistance to flow and, as a result, generate a high damping force. Conversely, a less viscous, or thinner fluid, would offer less resistance to flow and therefore generate a lower damping force.
- The Damper has electromagnetic actuators that create a variable magnetic field. When the magnetic field is activated by applying current, the metal-infused oil molecules bond together to form fibrous structures with a consistency, proportional to the intensity of the magnetic field. The intensity of the Magnetic field is proportional to the current applied to the actuator.
- Starting the third-generation onwards, MagneRide actuators now have two coils instead of one inside of each damper piston.
- The reason is that two coils allow the system to react faster, when it is deactivated. By using two electromagnetic coils wound in opposite directions, eddy currents nullify each other, causing the magnetic field to collapse almost instantaneously. This improved the reaction time of the damper by 12 milliseconds.
- When the magnetic field collapses, the oil molecular bonds separate and the MR fluid’s viscosity drops. The MR Fluid then passes easily through the pistons, reducing the damping force.
- The MagneRide system is connected to an Electronic Control Unit (ECU) that receives signals from the wheel-motion sensors and accelerometers.
- The ECU calculates the damping required at any particular instant and varies the damping force according to the User-selected Ride Mode.
- There are four modes: comfort, normal, sport plus, and race that the user can select from. “Normal” gives the best riding experience. It is a comfort-oriented calibration that can handle multiple driving situations and is more suited to daily driving on the street. “Sport plus” is more focused on a sporty style of driving where the steering response is more spirited. “Track” mode or race mode is perfect for road courses, autocross, as it offers the highest level of control. “Drag” mode focuses on pitch control for easy launches”.
What vehicles have MagneRide Suspension?
- Currently, MagenRide is available on the Cadillac CT4-V and CT5-V, and the CT5 Sport as standard equipment.
- In General Motors trucks, the RPO code Z95 denotes the Magneride Suspension. It is available as an option in all GM full-size SUVs like the Yukon, Tahoe, and Escalade, and as standard in the Denali Trim.
- In 2015, the Ford Mustang GT 350 and the Mustang GT 350R were introduced with the MagneRide suspension option.
- Other High-end sports car brands that incorporate the MagneRide Suspension are Ferrari, Lamborghini, Audi and Land Rover
In this brief article, we have discussed in-depth, the working principle of the MagneRide shock absorber and the vehicles that feature MagneRide suspension.
In case of any questions or queries, please feel free to ask.