transportation, future technology and vehicle concept - man using car control panel
Of the first 15 cars I owned, only one had power steering. Of the dozens I’ve owned since then, only one has not been equipped with steering assist.
So what changed? Why is power steering now standard equipment on everything in size from a Smart car on up, when a few decades ago it was an option, if available at all, on vehicles we now consider to be behemoths?
It’s not that we’ve turned into a nation of wimps, too lazy to turn a steering wheel without help — although most of us would probably find driving a vehicle from the ‘50s or ‘60s, without power steering, to be a workout today.
Other things have changed as well, making power assisted steering, to give it its proper name, a modern-day necessity.
In the early days of the automobile, vehicle wheels were tall and narrow, like the buggy wheels from which they evolved. Since then, they’ve grown almost continuously lower and wider.
Both those changes have increased the effort required to steer a vehicle, particularly at low speeds, as when parking.
In addition, with a few brief exceptions, cars and trucks have gotten bigger and heavier over the years. And an almost wholesale switch to front-wheel-drive on most mainstream cars in the 1980s added more weight on the front wheels, further increasing steering effort.
Coincident with all those changes, the driving population shifted from almost exclusively male in the early days to gender equality in the postwar era. And automakers quickly perceived that reducing steering effort would help them gain popularity among women drivers.
The first commercial passenger-car power steering system was offered on the 1951 Chrysler Imperial and Cadillac followed suit in 1952. By the end of that decade, it was widely available on most North-American cars.
But reduced steering effort wasn’t the only benefit to be realized.
Before power steering became common, steering wheels were much larger in diameter than they are now — to help maximize the driver’s leverage when trying to turn the wheels.
But with power assist, the steering wheels don’t have to be so big. Making them smaller in diameter enables not only a more comfortable driving position but greater room between the seat and steering wheel.
If you were to drive that ‘50s or ‘60s car without power steering today, you would probably also find it very slow — that is, you would have to turn the steering wheel more than you typically do now to make the same degree of turn.
That’s because in order to keep steering effort within acceptable limits, the steering ratio (steering wheel angle relative to actual steering angle) had to be much higher than is typical today.
The adoption of power steering meant that automakers have also been able to reduce the steering ratio, thus improving steering response in everyday sedans and SUVs to what were once considered sports-car levels.
The benefits haven’t all come without cost, however.
In principle, a power steering system works by exerting force on the steering gear, typically from either a hydraulic or electrical source, in addition to that provided by the driver via the steering wheel.
Various designs have been used to vary the amount of that additional force and to keep it proportional to the force or the degree of steering angle exerted by the driver.
The trick is to keep the system from adding so much force that the driver no longer feels a direct connection to the road.
Too many systems have gone too far in that direction, with the result that driving a car so equipped is as lacking in road feel as driving a video-game simulator.
Indeed, it has been my observation that there is now a whole generation of drivers who have never experienced true steering feel.
As a generality, electrically assisted systems tend to be particularly lacking in road feel, although that is not a blanket condemnation. Some manufacturers have developed very tactile electrically-assisted systems that are as rewarding to drive as their best hydraulically-assisted counterparts.
If they can do it, so can the rest. Which is a good thing, for the fuel-economy benefits resulting from the use of electric power steering systems means that they are likely to become the new norm.