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Comment by bunabhucan | Hacker News Reader

Mechanical engineer here, this article could have more detail and I'd have read it. The translation from nuts and bolts and rods and links in the suspension to the intangible but apparently important (for selling cars) "feel" is fascinating. It's sometimes idiotic - "make an Audi Q7 feel like a Porsche" required a movable central connection in the rear suspension for some rear wheel steer (but just using the existing play/travel) as well as a hydraulic then (v2) electric doo dah to counteract the tilt and keep the boat of a car level through turns. There's no "point" to this - it just let's them sell a souped up big SUV at 911 prices and make money hand over fist.

I'm not even a car person but this article wasn't laboring the point.

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I confused as to why the feel of a car driven at road speeds isn’t a “real”/valuable/relevant selling point in road cars. That’s a huge factor in my car purchases, and it’s the thing I remember most about my old cars.

Because that's not something that is typically checking in "test drives" nowadays. I was once yelled at by the Renault saleswoman for braking too hard during a test drive, even though I told here that I'm about to perform an emergency stop. She had us return to the dealership. I happily bought a Focus instead, the very next day, after a proper test drive.

But don't get me started on them providing a rear-disc-brake Focus for the test drive even though the trim level I was interested in had rear drums. Had I driven the drum model, I would not have bought it. But I acknowledge that I'm an outlier, who actually cares about how the vehicle handles and accelerates and brakes and takes potholes and how noisy it is at highway speeds and how it fares in a cross wind. The common, typical "test drive" doesn't cover any of those aspects anymore.

I appreciate this comment, and read the entire thing in Dwight Shrute’s voice.

Hang on, so multi tonne vehicles are designed with the rolling stock equivalent of anaerodynamic stability managed by black boxes?

I guess this is situated for latency but more likely installation and loom cost controls, close to the rear axle therefore more exposed to moving accident damage and at least to my casual reading of owner enthusiast fora unknown to educated owners and the public - rather like the Eurofighter Typhoon?

How can such designs pass DMV / MOT tests with inherent rolling instability in failure mode?

Or is there failsafe?

Edit: I should have said multi tonne vehicles intended by design to be driven fast and at limits including load limits.

It's called "dynamic chassis control" - it keeps the chassis level by pushing back against the torque forces in the sway bar. The equivalent vw or audi will have body roll. Most vehicles have a "u-shape" anti sway bar coupling the right and left side - the car still leans, just not as much. It's not a safety feature or a thing to keep all four wheels on the ground. It's a mechanical device that uses energy (from the engine) to counteract the torque in the sway bar for the purpose of keeping the chassis level.

Here is a picture of the part:

https://images.simplepart.com/images/parts/motor/parts/fulls...

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