Three tridents
The beam about B rotates at signed variable 'a' (a slider) times the uniform speed that the beam at C rotates; the 'delta' variable is the (slider) phase at B. The beam at B is displaced in initial phase by variable 'delta' from the right horizontal where 'gamma' starts; 'gamma' oscillates between just under 2pi and over 2pi. The three trident blades are colored red, green and blue, and numbered correspondingly 0, 1 and 2. The 9 intersection points of the blades are thus labelled 00, ..., 22. The three equilateral triangles are shown with a brown shading, and have vertex sets {00, 11, 22}, {01, 12, 20} and {02, 21, 10}. [The 10 label is hard to read as a result of some arcane bug, as far as I can see.]
As usual a, delta, gamma, B and C can be manipulated. The animated variable gamma oscillates between roughly -2pi and 2pi; when stopped it too can be set to a value on its slider.