Steering wheel seems like a simple component with a simple job – to turn the wheel in your desired direction. However, a lot of science goes behind this simple function. For instance, the Ackerman steering principle ensures an accurate turn. This principle explains the physics of different rear and front tyre angles as compared to speed while turning a vehicle.
Without the implementation of Ackerman, it becomes difficult for car manufacturers to design a vehicle that can turn accurately and steeply.
In this guide, we will provide you with complete details about the construction, working and usage of Ackerman steering mechanism in cars.
Ackermann Steering Mechanism
The Ackerman steering is widely used in vehicles for better handling. The earliest version of the steering has been modified with time into electronic and hydraulic steering systems but the basic principle is the same. See the following paragraphs which explain how does Ackerman steering work.
Background
Rudolph Ackerman in 1818 introduced a principle to resolve roll and slip problems found in early vehicles. There are other people also to claim the patent of this principle but he was the first one from Britain to achieve the patent. The issue of turning a vehicle from a steep manoeuvre was common in early automobiles and therefore the Ackerman principle became revolutionary for combustion engine automobiles.
Ackerman uses a four-bar linkage joined with an isosceles trapezoid platform due to the difference in rod length. Thus, different slip angles of tyres are produced which makes vehicle handling convenient.
Explanation
According to Ackerman, there is an instantaneous central point on which all the tyres rotate at different angles. The left side front tyre got a greater rotational angle contrary to the right side front tyres. Similarly, both the rear tyres make different angles which creates four different radii for four tyres.
Therefore, the tyre opposite to the turn covers a greater distance than the tyres on the other side. This is why right-side tyres rotate at a higher speed than left side tyres due to which all AWD and 4WD vehicles have differentials installed on their axles.
Working
Working of the Ackerman steering principle is simpler as it only uses different sizes of tyre rod and fixed link to ensure proper handling of the vehicle. The difference between the length of the fixed link and the operative link is adjusted by using the operative link. The shorter length of tyre rod focuses the inclination link on the rear axle. Therefore, when a car is turned, every tyre generates a different slip angle which provides convenience in turning the vehicle. Moreover, the inclination force will return the steering wheel to centre automatically at different angles and turns properly.
Advantages
Usage of the Ackerman principle on the steering system makes a unique system known as the Ackerman steering mechanism. There are multiple benefits of having an Ackerman steering system contrary to hydraulic or power steering systems.
- It prevents tyre from slipping outward while turning the vehicle.
- It increases the controllability of vehicles by using shorter tyre rods.
- Ackerman steering geometry makes the tyre toe-out which enables them to easily drive through steep manoeuvres.
Car Body Types and Usage of Ackerman
Car body type is one of the major elements that support the usage of Ackerman steering principle in the vehicle. The steering mechanisms are designed to operate under low-speed Ackerman or parallel steer. Sports cars and high-speed vehicles use parallel steering whereas Ackerman is preferred in sedans.
However, racing cars use the reverse Ackerman principle to avoid additional load on the outer tyres which are already suffering because of extra centrifugal force. The additional load and temperature can cause wear and tear to the tyre which is troublesome on the racing track.
This was all about the Ackerman steering mechanism used in the cars. The usage of the Ackerman principle provides better handling of the vehicle. If you are interested in using a vehicle with better handling browse through these used cars for sale in the UAE.
Stay tuned to UAE’s top auto blog for more information on steering mechanisms.
Related Posts
