The white longstock and the blind dog are considered classic navigation aids. The longstock lengthens the range of the arm, allows the determination of materials due to the impact noise or the transmitted vibrations, and thereby supports the echolocalization. Long-haul users go faster and safer than short-haul users. If the longstock is white, this tool is at the same time a globally recognized traffic sign for blindness (for the Federal Republic: Road Traffic Licensing Regulations. Intensively trained blind guide dogs with their holders together guide them past obstacles and can lead familiar paths completely independently.
Their owners report less stress, and they show a lower pulse rate when walking on unknown routes than pure long-haul users. Electronic mobility aids provide blind additional environmental information from a distance. The best scientific investigations have so far been the use of devices that emit ultrasound, receive their reflections, convert them into audible noises, and pass the results to the blinded. The user of these ultrasound aids must learn the device-specific “speech”, i. The allocation of the noises to the spatial situations. According to the manufacturers, a distinction is made between pure navigation and sensory aids. “Navigation aids” provide information to the blind in an easily understandable form. An example is the Sonic Pathfinder from Heyes . “Sensory Aids” provide their users with as much information as they normally see; This concerns navigation and orientation alike. One example is KASPA by Kay (called Trysensor at the trial stage). It has been shown in many cases that blind people who use ultrasounds in addition to the white longstock reach a higher degree of mobility: users of the Sonic Pathfinder touch fewer obstacles; Adults and children gain navigation and orientation skills with KASPA.
To describe blind ways adequately, falls seeing mostly difficult. By means of palpable (tactile) maps, blind people can already provide a “survey” of unknown areas in the run-up, because spatial conditions are represented here also spatially. However, the total “picture” from the sampled parts of the map must always be put together in the performance. By means of tactile maps, blind people can “comprehend” the spatial relationships in a relatively short time in the truest sense of the word. On the basis of such maps blind people orient themselves better on unknown surfaces than without them; They are quite suitable for blind children.
Streets, citizen blocks, and blocks of houses are presented differently in the original: the map sheet forms the street level; The first level over it (represented by a glued piece of paper) shows the citizen dough, the second level (even more paper) the cattle blocks. This realistic representation is called “positive block representation”. In this figure the three planes are symbolized by hatching; The higher the hatching, the higher the level. In addition to tactile maps, special measures of environmental design blindness can facilitate the orientation. These include, for example, The fortunately increasingly frequent traffic lights with acoustic additional signals, warning and control strips as well as traffic signs with voice information. Traffic signs can be provided with voice information.
A blinder with an infra-red directional device transmits the respective transmitter and receives the stored information therefrom. In doing so, he or she performs circular movements with the direction finding device in order to determine the direction of the signal, that is, the one in which it must go in order to reach the traffic sign. The corresponding technology was developed at the Smith-Cattlewell Institute in San Francisco. With their assistance, blind persons may, for example, The name of the street they are in. Correspondingly equipped bus lines announce their line number, and traffic lights “tell them at green”. Other persons are not bothered by all this information. Blind people are better informed by means of traffic signs with language information than by means of pre-given verbal directions.