Functions to convert spring parameters to and from mass/stiffness/damping and damping ratio/frequency response.

spring-utils.js

function convertDampingRatioResponseToStiffnessDamping(dampingRatio, response) {
  let mass = 1
  let angularFrequency = (2 * Math.PI) / response
  let stiffness = Math.pow(angularFrequency, 2) * mass
  let damping = dampingRatio * (2 * Math.sqrt(stiffness * mass))

  return { mass: mass, stiffness: stiffness, damping: damping }
}

function convertMassStiffnessDampingToDampingRatioResponse(mass, stiffness, damping) {
  let dampingRatio = damping / (2 * Math.sqrt(stiffness * mass))
  let angularFrequency = Math.sqrt(stiffness / mass)
  let response = (2 * Math.PI) / angularFrequency

  return { dampingRatio: dampingRatio, response: response }
}