Centre of Gravity in Cars and its Role in Driving
When it comes to analysing a car’s overall performance, its stability and handling are two very important factors. Both these factors depend on the car’s centre of gravity – a theoretical point on which all the weight of the vehicle is focused. While it may not be something car buyers focus on, it is of great importance for automotive engineers and car manufacturers as it is a parameter that helps in determining the ability of cars to turn steeply and the chances of rolling over. That is also why it is of great importance for rally and race car drivers.
In this guide, we will elaborate to you about the car’s centre of gravity meaning, working and calculation.
What is the Centre of Gravity in Cars?
The centre of gravity which is also known as the centre of mass is a theoretical focal point of the vehicle where all its components, weight and forces act effectively. In simpler words, it is the point where all the weight of the vehicle resides.
It changes when any additional element is included or excluded from the basic car structure for instance: it will increase if a panoramic sunroof is present and decrease if additional batteries are installed.
The higher the centre of gravity, the higher chances of the vehicle rolling over while turning through a sharp turn. Its role and impact on driving are discussed in the paragraphs below.
Centre of Gravity and Driving
The centre of gravity in cars is a principle known to every driver, as it significantly impacts the drivability of a vehicle. Any shift or inaccurate estimation of centrifugal or centripetal force incurred on the vehicle can impact the driving, turning, acceleration and braking abilities of the vehicle. The impacts of the centre of gravity on driveability conditions are mentioned below.
The car’s centre of gravity plays a measured role in turning a vehicle. When a car is driven through a turn the momentum of the vehicle is transferred in the direction of the turn which shifts the centre of gravity. If the centre of gravity is not accurate, the vehicle can roll over on the turn. A wider car wheelbase can be a potential solution to deal with a higher centre of gravity vehicle.
Acceleration and Braking
During acceleration or braking (deceleration) the centre of gravity acts over the force distribution between the tyres. When a stationary vehicle is accelerated gravity acts downward through the centre of gravity point. Whereas, reaction forces of the wheel act upward this creates a balance of force. This balance of force enables the braking system to work when forward force (acceleration) is reduced.
Similarly, when vehicles are provided with forwarding force (acceleration) the centre of gravity balances the air resistance and rolling friction enabling vehicles to move forward. Therefore, disturbance in the centre of gravity in cars can impact the overall functioning of the vehicle. It also impacts the road performance of the vehicle due to which many of them fail the ideal vehicle drivability and Moose test.
How to Drive Fast in High Centre of Gravity
The major drawback of having a higher centre of gravity is the proportionality of the vehicle rolling over. This issue is encountered when a vehicle is turned at a higher speed that does not coordinate with its gravity centre.
Here are some tips and precautions for driving a higher centre of gravity vehicle fast.
- Identify the areas which constitute a larger portion of the car’s weight and avoid anything that is making the vehicle too high.
- Ensure that the vehicle and car suspension is not soft (flexible). This will increase the chances of the vehicle rolling over.
- Independent suspensions are more preferred contrary to solid car axles in cars with a higher centre of gravity.
- Driving with flat tyres is not recommended as it will reduce the road grip of the vehicle.
SUVs, crossovers and pickups are the common cars with a higher centre of gravity. Therefore, when you are going off-roading in the UAE, ensure to apply these tips during off-roading.
How to Calculate Centre of Gravity of a Car
To calculate a car’s centre of gravity you can either use a centre of gravity calculator online or measure it manually. However, for both the calculation base weight, height and dimensions of certain components are necessary to be known. Here is the list of variables that are required for calculating the centre of gravity.
- Length of wheelbase
- Front weight of car calculated horizontally
- Rear weight of car calculated horizontally
- Radius of tyres
Once you have all these parameters you can measure the gravity focal point. The centre of gravity calculation formula is mentioned below.
Centre of Gravity=WB ✕ FWc/TW ✕ Tan Θ
WB= length of the wheelbase
TW= Total weight
Tan Θ= Tangent of angle
FWc= Change in weight (front weight − rear weight)
This was all about the centre of gravity in cars. Calculating the centre of gravity before purchasing a vehicle can be a difficult process and requires long calculations. We have listed some used cars for sale in the UAE with a lower centre of gravity for your convenience.
- Buy used Toyota Supra for sale in the UAE
- Buy second-hand Tesla Model X for sale in the UAE
- Buy used Aston Martin Vanquish for sale in the UAE
- Buy second-hand Audi A8 for sale in the UAE
Stay tuned to UAE’s top auto blog for more information on a car’s centre of gravity.