Tactile images of complex three-dimensional objects
Flexible use of the principle of spatial representation in tactile images
The principle to represent three-dimensional objects through technical design,
Ø From above
Ø From the front
Ø From the side
opens enormous possibilities.
Once this way of representing is understood, participants can handle even very complex drawings. Like: the architecture of a church.
In the example shown, from the book 'The Stones of Venice', the strict structure of 'from above, from the side and from the front' is used in a more flexible way. Morover the image links the plan to several side views.
At the bottom of the paper we see a 'from above'; the plan of the church. One line connects it to the 'from the side" (the east entrée), upper left corner. Another line connects to the 'from the side' of the absis (west), upper right corner. Between those we see the 'from the front', seen from the middle axe of the church (indicated by a dotted line).
This enables to fully understand the spatial organization of the church. Remember: a tactile image gives insight into a subject; it doesn’t give sight.
This basic principle guides the designer in order to make the blind reader understand the forms of an object and the position of the object and its elements in the space.
So the method is not a strict code, that prescribes, limits and forbids. On the contrary: the basic principles allow to show clearly the form of an object and its position in the space.
Another very illustrative example: the gondola, from the same book.
From the front one sees that the gondola is not symmetrical and leans towards the side of the standard of the oar. That side is 'thinner' than the other one. This construction explains why de gondolier only needs to row only on one side.
The asymmetry is very clear seen from above. The dotted lines help very much in perceiving it. This also shows clearly the position of the gondolier, the seats and the oar.
Finally the drawing from the side (in the middle); this one shows the vertical position of all the elements.
The blind reader now has a complete mental image of a gondola, without ever having been in one or having ever had a model of it.