The preparation of the blind student to use the tactile graphics

- understanding the relation between 3-dementional objects and 2-dimentional drawings.

Most illustrations such as pictures, diagrams, maps and comics become an indispensable part not only of textbooks, but also it is one of the basic means of conveying information that sighted students bring into play. Therefore, it is not astonishing that several attempts are made to adopt at least part of the graphics for blind learners. In view of the fact that removing some illustrations from the textbook, being the form of the adaptation, might find the teaching aims or a considerably large part of the tasks impossible to be attained. Undoubtedly , endeavours of changing pictures and drawings into tactile graphics might pose some questions but it needs to be mentioned that the adaptation of the buildings’ plans , towns and maps is acknowledged as an obvious necessity in the process of teaching blind learners.
An elementary complexity which the tactile graphic can cause among blind students is understanding the relation between objects, which are three-dimensional, and drawings being two-dimensional symbolic representations of these objects. To indicate the level of such a complexity it is sufficient to present a simple sketch of the table ( made by a sighted student) consisting of a horizontal line for the table top and two vertical lines for the legs.
A blind boy might find the concept of the table presented in such a way difficult (having discriminated it tactilely he stated that the drawing had three lines). Indubitably, the symbolic representation of the table does not resemble a three-dimension shape of the table with its hardness and smoothness. A table drawn by a blind child might be presented with the tabletop shown as a rectangular and four legs extending in all directions from the four corners of the tabletop, which to a large extent, explicates in what way a blind person perceives the table.
One of the educational tools allowing to better figure out the relation between three- dimensional objects and two-dimensional drawings is called Transfograph . It is a wooden box with sliding plates which easily transforms models of objects ( such as table, desk, fridge, chair) into tactile outlines, allowing blind students understand what comes about when a 3-dimensional object is represented as graphics on a flat sheet of paper.
Using the Transfograph during the lessons can be supportive with both interpreting tactile illustration and producing planned drawings by blind learners themselves. It gives the chance to understand ‘conventions’ used in drawings which blind learners will encounter in school textbooks.
It is important to point out that all designed tactile graphics need to be carefully planned by the teachers. To appreciate the importance of the issue it is worth quoting the description of the bus made by a blind child whose drawn bus consisted of three lines
One stands for the step, one for the bus seat and one for the vertical pole helping to board the bus, that is all the elements which the author of the drawing had a direct contact with. Therefore, if we make decision to adapt the drawings , we must take into account the experience the learner has had with the object that he/she is going to draw
The next important issue refers to all the details placed in the picture. Creating the tactile graphics there is a need to bear in mind that the produced graphics cannot be a strict copy of the drawing duplicated in the embossed version.
By looking at the drawing and familiarizing with the task ( point out on which piece of furniture a large book, medium size book or small book are placed or which of the animals is the biggest)) it turns out that most of the elements( such as a window, curtains, clouds) are not necessary to do the task. It is understandable that the first taken step is to divide the task into three separate parts removing unnecessary details and simplifying the drawing by presenting its elements systematically, omitting the impression of three dimensional perspective.