The MacPherson strut is the most common type of front suspension on modern cars, but what exactly is it and why does almost everyone use it?

If you enter this field with zero basic knowledge, then the MacPherson pillar can easily become an American football touchdown celebration like a suspension design decades ago. But as far as we know, this is only the latter, and this is where the fuss is.

MacPherson strut suspension is a simple independent suspension design, used by almost all major automakers in the world, and is usually used for the front wheels. It is based on a two-part basic triangular design; a control arm and a radius rod, which together form a triangle against the chassis of the car. Usually, this triangle is located at the bottom of the suspension instead of at the top.

The control arm positions the wheel laterally, and the radius rod prevents it from moving forward and backward in the wheel arch. The control arm is usually the thicker and stronger of the two, it is directly connected to the lower part of the wheel frame, also called the hub. Today, the two have been reduced to a larger control arm and combined with a stabilizer bar that connects the chassis and suspension unit.

Speaking of this, the spring and damper unit are installed vertically or close to each other. It consists of a closed cylinder, which is bolted to the top of the hub; inside it is a shock absorber or damper. At the top, it has a wide collar that can accommodate the coil spring, and the shock absorber shaft passes through the center of the coil spring to the top of the spring unit, which is bolted to the structure of the car.

In this way, the MacPherson strut creates a three-point fixed structure for the wheels, which proves to be very strong and versatile, and can be easily customized for more demanding uses such as track driving. At least as important, it is also a low-cost design. Car manufacturers like "cheap and effective" as much as we do.

As cars began to be produced with "one-piece" chassis (also called monocoques), this design really played a role. The monocoque body has a relatively high relative stiffness between the installation point areas of the MacPherson pillars, providing it with the support and control required for normal work.

Various developments over the years have seen different interpretations of the design, from Earle S MacPherson's first sketch, in which an extended anti-roll bar is also used as a radius bar, to the current idea, the two are separate. Some cars now also use a wishbone instead of the old control arm and radius rod combination.

This is obviously a good system. For example, when companies such as BMW and Porsche use it, you will find it hidden behind the front wheels of the Golf GTI. It is not only suitable for shopping carts, although 99% of them use the same basic design.

The double wishbone setup allows more adjustments to the camber angle and roll center, thereby reducing body roll. This is also a stricter choice, and some people say it introduces more control to the car's handling. The fact remains that MacPherson struts are an excellent and effective way to combine strength, springs and stability with low manufacturing costs.

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