Engineering software or designing?

engineering software just to draw the blocks as the picture without any simulation

You could do that drawing in PowerPoint.

thanks you 

Best regards 

I would use either Inkscape (free) or Illustrator (not free).

I use both, and depending on the client, and their needs, can recommend either.

(Illustrator examples of mine:

http://www.bipbip.info/jg/vector3.html

You can use RFFLOW flow chart software or Smart draw. There are few  inbuild engg., control devices. Unfortunately both are not free. but demo copy is free. 

Any CAD or vector software. adobe Illustrator could also be used.

You can use Adobe Flash and export result in image format. Using of flash is easier than Illustrator.

Inkscape for 2D and Blender for 3D pictures.

Blender for animations

For instance: https://www.youtube.com/watch?v=RasemoYzsFA