The notion of mobility is a very broad concept, grouping together all of the mental processes as well as the actions necessary to move, sufficiently autonomously and efficiently, to the desired destination. Overall, mobility therefore designates an individual's ability to move in space.

In the event of reduced mobility, certain tasks or situations become disabling because they cannot be carried out without assistance, greatly reducing the autonomy of these individuals. The reasons for a loss of mobility can be many, and one of them is the loss (or deterioration) of vision.

In fact, mobility, in addition to the ability to move, requires knowledge of the surrounding space in order to be able to orient and navigate to the target to be reached, while taking into account the constraints of the environment (obstacles, names of streets, presence of known monuments, location of the nearest pedestrian crossing…). Most of this relevant space information is acquired through vision, which makes mobility of people with visual impairment (PPIV) very problematic, but not impossible.

This knowledge of the surrounding space can be acquired through other sensory modalities, for example by using the surrounding sound space and reflection on nearby obstacles, and by using a cane to detect nearby obstacles.

However, moving around on the basis of hearing and tactile cues will require visual impaired people a lot of training, and will never allow them to recover a level of autonomy similar to that of sighted people on all tasks involving vision. Indeed, vision allows access to information that is simply not captured by other sensory modalities, such as for example the position of obstacles emitting (or reflecting) no sound, being out of reach of the cane or too high for it.

This is where electronic navigation aids come in, artificially capturing relevant information about the environment, to transmit it to the wearer by another sensory modality, typically tactile or auditory.

For more information, follow the link to projects on navigation of visually impaired people in LITIS LAB.