Suspension (Vehicle)
Introduction
A vehicle suspension is a system that connects a vehicle to its wheels and allows relative motion between the two. It is designed to maximize the friction between the tires and the road surface, provide steering stability, and ensure the comfort of the passengers.
History
The history of vehicle suspension dates back to the invention of the wheel. Early suspension systems were simple and consisted of leaf springs – a stack of arcs of steel – attached to the axles. The first vehicles with suspension were likely horse-drawn carriages. As technology advanced, so did suspension systems, with the introduction of more complex and efficient designs.
Types of Suspension Systems
Suspension systems are broadly classified into two categories: dependent and independent suspension.
Dependent Suspension
In a dependent suspension, the motion of one wheel is dependent on the motion of the other. This type of suspension is commonly found in older vehicles, particularly those with a solid axle. There are two main types of dependent suspension: the beam axle and the live axle suspension.
Beam Axle Suspension
The beam axle suspension is one of the oldest and simplest types of vehicle suspension. It consists of a solid metal bar that spans the width of the vehicle and connects the wheels on either side. This design is robust and durable, but it does not provide a high level of comfort or handling performance.
Live Axle Suspension
The live axle suspension, also known as a solid axle suspension, is similar to the beam axle design. However, it incorporates the drive shaft, differential, and drive axles into a single unit. This design is commonly used in rear-wheel-drive vehicles.
Independent Suspension
In an independent suspension, the motion of one wheel is not dependent on the motion of the other. This type of suspension provides better handling and comfort compared to dependent suspension. There are several types of independent suspension, including MacPherson strut, double wishbone, and multi-link suspension.
MacPherson Strut Suspension
The MacPherson strut suspension is a type of independent suspension that uses a strut as a major structural component. It is simple, cost-effective, and widely used in many modern vehicles.
Double Wishbone Suspension
The double wishbone suspension, also known as an A-arm suspension, is a more complex type of independent suspension. It provides better control over the camber angle of the wheels, allowing for improved handling and stability.
Multi-Link Suspension
The multi-link suspension is a type of independent suspension that uses three or more lateral arms and one or more longitudinal arms. This design allows for a high degree of control over the vehicle's motion and is often used in high-performance vehicles.
Suspension Components
A vehicle suspension system is made up of several key components, including springs, shock absorbers, struts, control arms, and anti-roll bars.
Springs
Springs are the primary components that absorb and store energy from road irregularities. They compress and expand to absorb the kinetic energy from the wheels, reducing the impact felt by the vehicle and its occupants.
Shock Absorbers
Shock absorbers, also known as dampers, are designed to dampen the oscillations of the springs. They convert kinetic energy into thermal energy, which is then dissipated into the atmosphere.
Struts
Struts are a structural part of the suspension system that carry the load of the vehicle and provide a mounting place for the coil spring and shock absorber. In some designs, the strut also serves as the steering pivot.
Control Arms
Control arms, also known as A-arms, are hinged suspension links that connect the chassis to the suspension upright or hub that carries the wheel.
Anti-Roll Bars
Anti-roll bars, also known as sway bars, are used to reduce body roll during cornering. They are connected to the suspension components on either side of the vehicle and help to maintain balance and stability.
Suspension Tuning
Suspension tuning is the process of adjusting the characteristics of a vehicle's suspension system to optimize its performance. This can involve adjusting the spring rate, damping force, ride height, camber angle, and other parameters. Suspension tuning can significantly impact a vehicle's handling, ride comfort, and overall performance.