Automotive suspension design is an aspect of automotive engineering

Automotive engineering

Modern automotive engineering, along with aerospace engineering and marine engineering, is a branch of vehicle engineering, incorporating elements of mechanical, electrical, electronic, software and safety engineering as applied to the design, manufacture and operation of motorcycles, automobiles,...

, concerned with designing the suspension

Suspension (vehicle)

Suspension is the term given to the system of springs, shock absorbers and linkages that connects a vehicle to its wheels. Suspension systems serve a dual purpose — contributing to the car's roadholding/handling and braking for good active safety and driving pleasure, and keeping vehicle occupants...

 for cars and trucks.

The process entails

• selecting appropriate vehicle level targets
• selecting a system architecture
• choosing the location of the 'hard points', or theoretical centres of each ball joint
  Ball joint
  In an automobile, ball joints are spherical bearings that connect the control arms to the steering knuckles.More specifically, a ball joint is a steel bearing stud and socket enclosed in a steel casing. The bearing stud is tapered and threaded. It fits into a tapered hole in the steering knuckle. A...
  
   or bushing
  Bushing (isolator)
  A bushing or rubber bushing is a type of vibration isolator. It provides an interface between two parts, damping the energy transmitted through the bushing. A common application is in vehicle suspension systems, where a bushing made of rubber separates the faces of two metal objects while allowing...
  
  
• selecting the rates of the bushings
• analysing the loads in the suspension
• designing the spring rates
• designing shock absorber
  Shock absorber
  A shock absorber is a mechanical device designed to smooth out or damp shock impulse, and dissipate kinetic energy. It is a type of dashpot.-Nomenclature:...
  
   characteristics
• designing the structure of each component so that it is strong, stiff, light, and cheap
• analysing the vehicle dynamics
  Vehicle dynamics
  Vehicle dynamics refers to the dynamics of vehicles, here assumed to be ground vehicles. Vehicle dynamics is a part of engineering primarily based on classical mechanics but it may also involve chemistry, solid state physics, electrical engineering, communications, psychology, control theory,...
  
   of the resulting design

Since the 1990s the use of multibody simulation and finite element software has made this series of tasks more straightforward.
A partial list [1] would include:

• maximum steady state lateral acceleration (in understeer mode)
• roll stiffness (degrees per g of lateral acceleration)
• ride frequencies
• lateral load transfer percentage distribution front to rear
• Roll moment
  Roll moment
  In a vehicle suspension, roll moment is the moment of inertia of the vehicle's sprung mass . The roll moment is the product of the sprung mass and the square of the distance between the vehicle's roll center and its center of mass...
  
   distribution front to rear
• ride heights at various states of load
• Understeer
  Understeer
  Understeer and oversteer are vehicle dynamics terms used to describe the sensitivity of a vehicle to steering. Simply put, oversteer is what occurs when a car turns by more than the amount commanded by the driver...
  
   gradient
• Turning circle
  Turning radius
  The turning radius or turning circle of a vehicle is the size of the smallest circular turn that the vehicle is capable of making. The term turning radius is actually a misnomer, since the size of a circle is actually its diameter, not its radius. The less ambiguous term turning circle is preferred...
  
  
• Ackermann
  Ackermann steering geometry
  Ackermann steering geometry is a geometric arrangement of linkages in the steering of a car or other vehicle designed to solve the problem of wheels on the inside and outside of a turn needing to trace out circles of different radius...
  
  
• Jounce travel
• Rebound travel

Once the overall vehicle targets have been identified they can be used to set targets for the two suspensions.