Not all scientific concepts can be developed by using 2D videos only, but sometimes 3D technologies videos are required in explaining complicated models, and hard concepts.
Here the instruction designer with the help of the Subject matter expert puts a complete imagination for the 3D video in general, and for the used models in specific. Photographing the real model may be a must or SME provides the model real photos from different scientific references.
After that the designers team start modelling the 3D objects with the required details level as in the video scope, and these designs got reviewed by the instruction designers and subject matter expert.
After approval of the designs, the animator team start animating the 3d objects in sync with the narration and required special sound effects. After that the instruction designers and subject matter experts review and approe every detail in the video, and the quality control team review the outcome of each phase, and also review the final output.