Letter | Published:

Combined Mobility System for the Blind

Nature volume 222, pages 13011302 (28 June 1969) | Download Citation



THE most potentially useful electronic guidance aid for the blind which is generally available is the Ultra Sonic Aid (produced and marketed by Ultra Electronics Ltd, Western Avenue, London W3). Essentially, this aid is a narrow beam ultrasonic device which provides its blind user with an auditory representation of certain aspects of the immediate environment. The audio-output of the aid is an analogue display of the distance (coded with respect to audio-frequency) between the aid and the object in space being interrogated. The auditory display also allows coding of texture, movement and angular displacement (determined by a scanning technique) of distant objects which fall within the ultrasonic transmission area of the device. The normal maximum range of the aid is between 8 feet and 10 feet. Full descriptions of the operational characteristics of the aid and its evaluation have been published1–4.

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  1. 1.

    , J. Brit. Inst. Rad. Eng., 24, 309 (1962).

  2. 2.

    , and , National Physical Laboratory Report No. AP 20 (1965).

  3. 3.

    Editorial in New Beacon, No. 613, 113 (1968).

  4. 4.

    , and , American Foundation for the Blind, No. 4, 70 (1904).

  5. 5.

    , Proc. Intern. Cong. on Sensory Devices for the Blind (edit. by Dufton, R.) (St Dunstan's, London, 1967).

  6. 6.

    , in , Blindness (Princeton Univ. Press, 1950).

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  1. Department of Psychology, University of Nottingham, Nottingham.



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