This is less rigid and formulaic than the well-trodden area of using geometry and human proportion to draw human figures.
You won't find any rules such as "the x has to by y times longer than the z" like you will in much of historical figure drawing. However, it does do the same process of finding a form and applying shapes and proportions to envelop/approximate the form. This type of process, and its converse (deriving forms from basic geometrical techniques) is very old and very widely used. Architects and figure artists both have literature extending back to ancient times of how to draw pictures using geometric techniques (I use the term "geometric techniques" loosely here, can't think of a better word at the moment).
For logo design, instead of deriving an image solely from shapes, often a reference picture (e.g. the bunny in your pic) or mental image is started with, and the artist creatively uses whichever geometric shapes or techniques he sees fit in order to capture the essential shape of the reference. Often because the image has been rendered using these geometric techniques, the lines are smoother, have a better sense of proportion, and the form is simpler, all of which lend a pleasing aesthetic. Other times, if you leave parts of the shapes (like in your images), the image is made seemingly more complex, and this can be pleasing too.
A good demonstration of a similar technique can be found in Peter Johnsson's theory of how swords were designed in medieval and renaissance Europe. Note how in order to achieve the sword form, various triangles, shapes, and proportions are used as the designer sees fit, and not necessarily because of some rigid, underlying formula.
To learn about these geometric techniques, I highly recommend the game Euclidia It will introduce you to the different ways you can construct things using basic geometric operations. Once you gain this knowledge, be creative with them and try to construct other objects with your newfound skills. And after you get the hang of it please show me what you've made!