As from the name, Yes, Anti-roll bars do prevent your car from rolling over. Anti-roll bars prevent your car from rolling sideways. Those who don’t know what anti-roll bars are, need not fear because they are nothing more than a bar or a rod. Yes, a single rod is used to prevent your car from rolling sideways and your life safety along with your family’s safety depend on that single bar many times. Let’s know who these engineers can let a single rod decide your and your family’s security.
Anti-roll bars basically consist of a single rod connecting to the left and right wheel of the car, connected via suspension. Of course, the connection would not be made directly to tires as it will cause the rod to start rolling every time the wheels roll. Before we know the working of these bars, we need to know why the rolling happens in your car.
The roll (sideways) happens only on turns and it happens because of the heavy weight of your car. As your car is taking a turn, the outer-most wheel of the car gets all the weight of the car due to shift in weight because of centrifugal force acting on the whole body. This lets all weight being shifted to outermost wheel and the inner wheel can lift off from the road and hence your vehicle can start rolling sideways thereby giving you free but injurious roller-coaster ride.
So, the function of the anti-roll bar is to hold that inner wheel onto the road and give you a comfortable ride. This happens because anti-roll bar connects two wheels and the stiffness of bar lets the weight being distributed equally on both wheels and letting both wheels on road.
Anti-roll bars also decide the understeer and oversteer capacity of the vehicle. You can read more about it understeering and oversteering over here. To increase the value of understeer, the stiffness of front sway bar (anti-roll bar) is increased. This means if you increase the stiffness of front sway bar, it will give distribute the load of vehicle equally on both tires, thereby decreasing the value of centrifugal force (which helps in turning by providing angular momentum as the vehicle leans outward), this will cause the vehicle to turn less at high speed when you turn the steering wheel more.
In a similar way, to increase oversteer, the front sway bar is removed which lets the weight being distributed unequally on wheels while turning, hence increasing the centrifugal force.