Talk:Multi-link suspension

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Plan view = view from above?[edit]

I'm guessing that a plan view is the view from above? Thanks --Badger151 15:31, 18 September 2006 (UTC)

Yes. We usually say front elevation, side elevation, plan view for a building, front view, side view, top view for a suspension, but that is not a fixed rule.Greglocock 23:39, 18 September 2006 (UTC)

Toe Bar[edit]

What is the point of the toe adjustment bar? Three points are the minimum to define a plane. The pair of links for the upper and lower "control arms" are required for stiffness/compliance I assume, but wouldn't that be more than sufficent to control the wheel movement?

I think you mean the toe link, or tie rod. In general it allows us to steer the wheel as it moves vertically, typically by very small amounts. Often suspensions are designed with extra links in, these rely on deflection in the bushes in order to let the suspension move. Greglocock 04:30, 9 October 2006 (UTC)
The above answer is blatantly incorrect. Sorry, suspension is not designed with "extra links." It does however rely on bushing compliance in some instances. A good example is during roll with a 4 link beam axle. Theoreticaly, if the links only constrained the distance between the mounting points, there would be no binding and no deflection of the bushings or bearings. However, in most cases, these links utilize round bushings at the mounts. This means not only is the distance between the mounts constrained, they are also "constrained" so that they remain at the same angle relative to each other. Obviously when the car is rolling, the angle between the axle and the sprung mass changes, and thus the angle between the mounting points changes. In order to accomodate this, the bushings must be able to deflect a certain amount to prevent binding.
And as for the toe link, you are correct when you state that three points are all that is needed to define a plane. And that is percisely the function the toe link provides. Compare a multi-link independent suspesion to a double withbone(short long arm) setup. Each A-arm provides one defined point. The same is true for each of the two links in a multi-link. By being angled towards each other, they locate the point at their theoretical intersection. So each pair of links, which function as A-arms, locates two points. These two points dictate the kingpin axis. The third link, the toe link, contrains the wheels rotation around this axis. in the case of the front wheels, the length of the toe rod is controlled by steering input. In the rear, these are solid links which ensure that the tires continue to point down the road. —Preceding unsigned comment added by (talk) 20:44, 17 April 2011 (UTC)
"The above answer is blatantly incorrect. Sorry, suspension is not designed with "extra links."" Yes they are. For example the Opel STA suspension worked very well for many years, in the sort of awful way that semi trailing arms do. Lotus added an extra link to tidy it up. Or as another example, the Ford Falcon rear suspension use 4 parallel longitudinal links. Strictly speak only 3 were necessary, since the watts link provided lateral location. Your other post is full of tripe as well. Enjoy. Greglocock (talk) 22:27, 17 April 2011 (UTC)

Top link[edit]

I'm looking for somewhere to add a description of a 'top link', which I would describe as being like an upper wishbone, but with only one arm! Racing cars of the 1960s or thereabouts often had a rear suspension set up of a lower reversed wishbone with two radius rods and a single top link: I guess this could also be defined as a multi-link suspension, albeit a rather crude one, since without any means of accurately computing the effects of the different suspension members control would have been, erm, basic at best. Is this an appropriate place to cover this? 4u1e 22:27, 28 April 2007 (UTC)

Innaccuracy/confusing statement[edit]

In the opening paragraph where beam axle suspension is addressed, the article says that the most common multi-link is a 4 link with a panhard rod. While the panhard setup is technicaly a 4 link, almost no where is it actually refered to as such. It is refered to as a three link, with which the panhard bar acts as the fourth restraint. With the current wording, it almost suggests (if one where to interpret the wording as is most common) that the most common solid beam configuration is one which utilizes four links as well as a panhard bar. Sorry, but unless all the (non-panhard) links use spherical bearings and are parallel, that equals out to be a total of 6 degrees of restraint (1 for each link, 1 for the panhard, and 1 for the funadmental beam axle configuration). In other words, the tires could not move without putting the links into severe bending. —Preceding unsigned comment added by (talk) 20:22, 17 April 2011 (UTC)

Half a million Holden Commodore drivers might suggest that the wheels go up and down just fine with that configuration. What you are missing is that one of the longitudinal links is redundant, and that redundancy is removed via bush compliance. 4 link+watts, which has the same simple dof count, is used for Supercar and was also used for Ford Falcon for many years.Greglocock (talk) 23:37, 9 May 2013 (UTC)

General Description of MultiLink Suspension[edit]

This is a very confusing description of car suspension design. I read the article and was no wiser afterwards but I have a suggestion. I believe the term 'Multi-Link' should not be applied generally to any suspension system with multiple links, but specifically to the complex modern variations on the double wishbone (A arm). These are typically (but not exclusively) used on the front of German cars - Mercedes, BMW, Audi. Double Wishbones, Trailing Arms, Beam Axles, McPherson Struts, Sliding Pillar, Swing Axles and the like are relatively easy to understand but still require good diagrams. Multi-Link are much more difficult to visualise - incomprehensible without excellent diagrams. If you could add some diagrams with different colours for each individual link it would go a long way to helping readers to grasp the concept. WPAJ (talk) 11:03, 16 March 2013 (UTC)

Image problem[edit]

the first gif image on the page showing the setup working from the rear view is non repeating unlike the second image from the top view (talk) 15:57, 9 May 2013 (UTC)