abstract type AbstractSimpleMotion{T<:Number}

Provides an analytic motion for uniaxial strain

This is

\[\mathbf{F} = \begin{bmatrix} \lambda_1 & 0 & 0 \\ 0 & \lambda_2 & 0 \\ 0 & 0 & 1 \end{bmatrix}\]

Provides an analytic motion for uniaxial strain

This is

\[\mathbf{F} = \begin{bmatrix} \lambda & 0 & 0 \\ 0 & \frac{1}{\lambda} & 0 \\ 0 & 0 & \frac{1}{\lambda} \end{bmatrix}\]

Provides an analytic motion for uniaxial strain

This is

\[\mathbf{F} = \frac{1}{2}\begin{bmatrix} \left(\lambda + \lambda^{-1}\right) & \left(\lambda - \lambda^{-1}\right) & 0 \\ \left(\lambda - \lambda^{-1}\right) & \left(\lambda + \lambda^{-1}\right) & 0 \\ 0 & 0 & 2 \end{bmatrix}\]

Provides an analytic motion for simple shear.

This is

\[\mathbf{F} = \begin{bmatrix} 1 & \gamma & 0 \\ 0 & 1 & 0 \\ 0 & 0 & 1 \end{bmatrix}\]

Provides an analytic motion for uniaxial strain

This is

\[\mathbf{F} = \begin{bmatrix} \lambda & 0 & 0 \\ 0 & 1 & 0 \\ 0 & 0 & 1 \end{bmatrix}\]

Document me

displacement_gradient(
    motion::ConstitutiveModels.AbstractSimpleMotion{T},
    args...
) -> Tensors.Tensor{2, 3, _A, 9} where _A