Panhard bars and Watt's links control the lateral location of a live axle. That is, they keep the axle from moving side-to-side (laterally).
横向稳定杆和瓦特连杆控制车轴的侧向移动。
This is a Watt's link:

The ends of the blue bars are attached to the chassis. Note how the axle is free to move up and down, but it can't move side-to-side.
蓝色连杆的一端与底盘相连，请注意车轴可以上下自由活动，但不能侧向活动。
Here's a panhard bar:

This works similarly, except it's one long bar that's attached to the chassis on one end and the axle on the other. The lateral movement shown in the diagram is not that much in real life.
横向稳定杆的工作原理与上面类似，稳定杆的一端与底盘相连，另一端与车轴相连。
The Mustang has neither of these devices - it relies on the four links in the rear to keep the axle from moving side-to-side. Unfortunately it doesn't do a very good job of it, as you know if you've ever hit a bump while turning. That's why people ditch the upper control arms and do the torque arm and panhard bar (or in extreme cases, torque arm and Watt's link). A bunch of vendors have panhards for Mustangs; Griggs is the only shop I know of selling a Watt's link.
野马没有上述任何装置，它依赖四连杆机构来防止车轴的侧向移动，不幸的是效果并不好，如果你在转向时压过一个凸起你就有体会了。这就是为什么人们抛弃四连杆机构而采用扭力梁加横向稳定杆的原因（极端的例子是扭力梁加瓦特连杆）。

A lot of cars do come with panhard bars - the F-bodies have them along with a torque arm, and the Chevy Trailblazer has one with a parallel 4-link rear setup (similar to the Steeda "5-link" in concept). The Crown Vic has a 4-link rear with a Watt's for lateral location.
There are some diagrams in the Herb Adams book showing each type of suspension - when I get around to it I'll scan a couple and throw them up.
I ripped off these diagrams from Total Control Products - they build a Watt's setup for classic Stang.
这是我google到的一篇介绍瓦特连杆文字，貌似是国外汽车论坛上的post，那个论坛貌似是叫野马（Mustang）的。文中介绍了瓦特连杆、横向稳定杆的工作原理，顺带还提了一下四连杆的弊端。我配了大致的翻译，本人不对原文的和译文的正确性负责（也许发这篇帖子的家伙是托呢 ），供车友参考。
[ 本帖最后由 lostcity 于 09-10-27 09:52 编辑 ]

晕，图片怎么弄过来？

不错，顶。原来还是以为是类似2连干的结构呢

你看得到图？我自己怎么看不到？

对啊，我也看到了，好像在野马上应用的挺多的，还有的文章介绍提到很多高性能车都有瓦特连杆，看来新雅特的后悬也不是一无是处啊，既节省了空间，性能也可以

按文中所述，扭力梁+瓦特连杆似乎好过多连杆，又省钱又NB。
哪位达人能解释一下，新君威为啥不用这NB的扭力梁，而用既费钱效果又差的多连杆呢？

“The Mustang has neither of these devices - it relies on the four links in the rear to keep the axle from moving side-to-side. Unfortunately it doesn't do a very good job of it, as you know if you've ever hit a bump while turning. That's why people ditch the upper control arms and do the torque arm and panhard bar (or in extreme cases, torque arm and Watt's link). A bunch of vendors have panhards for Mustangs; Griggs is the only shop I know of selling a Watt's link.
野马没有上述任何装置，它依赖四连杆机构来防止车轴的侧向移动，不幸的是效果并不好，如果你在转向时压过一个凸起你就有体会了。这就是为什么人们抛弃四连杆机构而采用扭力梁加横向稳定杆的原因（极端的例子是扭力梁加瓦特连杆）。”
对于车轮外倾或者内倾等这轮轴向的加速度，目前的四连杆对此抑制很差，是因为橡胶圈的形变。在大部分的此类情况下抗车轮侧倾方面尚不如扭力梁。
我不知道原文中‘The Mustang’是指什么车，不过我不认为4连杆的车会不配置平衡杆或者类似的装置，要不然转弯的侧倾会让“神车迷”们难以想象！
目前最好的方案 应该还是多连杆 + 平衡杆 最好再加防倾杆
不知道 英朗的 扭力梁+瓦特连杆 效果如何
[ 本帖最后由 prophets 于 09-11-26 20:43 编辑 ]

The Mustang 就是福特野马