InSIght focused on understanding what information people who are visually impaired get from symbols and illustrations. One in 30 Europeans experiences sight loss, including one in three individuals over 65 years of age (European Blind Union; EBU). These individuals cannot read the newspaper or the name of a street, recognise a face or read a symbol, use a map or an illustration: they rely on their sense of touch. Symbols and illustrations typically provide important, often life- saving information – ‘flammable’, ‘fire evacuation route’, ‘poisonous’, etc.
{image - poison} {Image - Flammable}
Symbols and illustrations are pictures: they embrace the conventional shape of certain phenomena (Oxford Dictionary), i.e. the configuration of angles, curves, and straight lines. Individuals who rely on their sense of touch seek information from tactile symbols and illustrations; these are usually embossed, i.e. they stand out in relief. Those who rely on their sense of touch mix up over 70% of angles and curves, stating the following – ‘Angles and curves are the same thing.’; ‘An angle is a pointed or sharp curve. Also an angle is curved.’; ‘A curve is more open than an angle.’; ‘When the shape has more than two lines, then it is a curve; not an angle.’ Tactile symbols and illustrations tend to be embossed copies of the corresponding visual symbol or illustration, which are rarely, if ever, altered (e.g. in line straightness and/or curviness) to make it easier to perceive angles, curves, and straight lines correctly.
The accessibility symbol provides an example of the problems caused by mixing up angles and curves; the mix-up makes it hard to make out the body and the wheel. His or her actively exploring fingers become caught up in the wheel (circle) and he or she thus fails to detect the hip and knee (angles). This makes it impossible to discriminate the accessibility symbol from any other circle.
The accessibility symbol (in which the white lines would be embossed):
{image - accesibility symbol} {image - accesibility symbol curves}
The actual symbol How the symbol may be represented if angles are perceived as curves
The Euro symbol (€) provides another example. If angles and curves are mixed up, this may very easily be mistaken for the capital E. Mixing up angles and curves also causes problems at school. Consider the illustration of the Pythagorean triangle. If the pupil perceives the 90° angle as a curve, he or she will find it difficult to grasp the concept the illustration is intended to convey; the Pythagorean theorem. Still, tactile symbols and illustrations are important: more than 90% of people who need braille do not read it well (European Blind Union; EBU).
The primary objective of InSIght was to investigate in which configuration(s) of shape features angles are perceived as angles, curves as curves, and straight lines as straight lines – and if
misperceived, why. InSIght aimed to contribute to the development of universal design standards for tactile symbols and illustrations (cf. the EU 2010-2020 Disability Strategy).
