Lumped-elements systems can be used for modelling and/or analysis of:

• Systems that can be considered as linear
  condition fulfilled under small-signal conditions
• Systems without any propagation effects
  limitation by system dimensions to wavelength ratio that must be sufficiently smaller than 1

Basic idea: mechanical system can be decomposed into a certain number of ideal elements:

• Mass elements
  carry uniquely the potential energy
  non-deformable and non-dissipative
  analogy to electrical inductors
• Elastic elements
  carry uniquely the elastic energy
  zero-mass and non-dissipative
  analogy to electrical capacitors
• Dissipative elements
  non-deformable and zero-mass
  analogy to electrical resistors

Two conjugate power variables to quantify the relations within a circuit

• Effort e(t)
  
• Flow f(t)

Dimension of the product e.f is a power

Two variables assigned to element terminals

• Through variable
  traverse an element
  can be associated with the current in electric circuits
  
• Across variable
  identified between two terminals of an element
  corresponds to the voltage in electric circuits