There is a type of visual programming which is applied to virtually everything around you of some mechanical complexity: interactive geometric constraint solvers.

In CAD tools like SolveSpace, SolidWorks, Inventor and several others, the dimensions of objects are not described directly, but instead through a set of constraints such as “these are orthogonal”, “these have this distance”, “this is a tangent” etc. If you have never used it, try SolveSpace, which is free.

Albeit highly declarative, it is absolutely a programming language for a specific domain. It doesn’t try to be good at describing imperative programs or flows; instead it presents a paradigm which is very different, but fits perfectly in the problem domain of mechanical designs.