Wikipedia
Lidinoid
In differential geometry, the lidinoid is a triply periodic minimal surface. The name comes from its Swedish discoverer Sven Lidin (who called it the HG surface).
It has many similarities to the gyroid, and just as the gyroid is the unique embedded member of the associate family of the Schwarz P surface the lidinoid is the unique embedded member of the associate family of the Schwarz H surface. It belongs to space group 230(Ia3d).
The Lidinoid can be expressed as a level set:
$$\begin{align}
(1/2)[&\sin(2x) \cos(y)\sin(z)\\
+ &\sin(2y)\cos(z) \sin(x)\\
+ &\sin(2z)\cos(x) \sin(y)]\\
-& (1/2)[\cos(2x)\cos(2y)\\
+ &\cos(2y)\cos(2z)\\
+ &\cos(2z)\cos(2x)] + 0.15 = 0
\end{align}$$