@online{olson2025,
  author = {Olson, Dieter},
  title = {Screw {Theory} {Reference} for {Control-Affine} {Multibody}
    {Dynamics}},
  date = {2025-11-28},
  url = {https://affinedrift.com/articles/screw-theory-reference.html},
  langid = {en},
  abstract = {Twist and wrench duality gives a consistent language for
    spatial mechanics. This reference derives the required frame maps,
    qualifies wrench inversion, and connects rigid-body balances to
    constrained multibody dynamics and explicitly defined
    counterfactuals.}
}