GM Develops Adaptive Springs for Suspension Systems

General Motors is trying to apply the technology from adaptive dampers to springs for future suspension systems, showing a patent application that recently surfaced.

GM was a pioneer in magneto-rheological dampers, which use magnetic fluids to rapidly change the hardness of dampers. In a patent application published by the U.S. Patent and Trademark Office (USPTO), Nov. 2024/7, GM submitted to 2023/5/5 The automaker has also laid out the design of the magnetic rheology spring.

Magneto-rheology works by using magnets to adjust their viscosity, which occurs when metal particles in a fluid react to a magnetic field. This is currently used in dampers to switch between firm and soft settings, but in documents GM will discuss using it to adjust the spring rate to highlight performance or ride comfort as needed.

The design of the patent application includes 2 separate springs with a central seat in the middle. The seat has an outer sleeve that contains a magneto-rheological fluid, along with an electromagnet. When the magnet is energized, the fluid becomes thicker and inhibits the movement of the spring. Non-energizing magnets allow for more spring movement and thus more suspension travel.

Adaptive integrated with future versions of the MagneRide damping system used in current GM models, although all patented ideas make it into production

Similar patent applications from other automakers have not emerged recently, but Ford has developed a new version of the MagneRide damping system used in the Chevrolet Colorado ZR2 and/or other GM off-road trucks. The Multimatic DSSV (Dynamic Suspensions Spool Valve) appears to be working on position-sensitive dampers to counteract dampers.