A Tool for Range Sensing and Environment Discovery for the Blind

This paper describes the development of a hand-held environment discovery tool for the blind. The final device will be composed of a laser-based range sensor and of an onboard processor. As the user swings the hand-held system around, he/she will receive local range information by means of a tactile interface. In addition, the time profile of the range will be analyzed by the onboard processor to detect environmental features that are critical for mobility, such as curbs, steps and drop-offs. In our current implementation, range is collected by a short-baseline triangulation system formed by a point laser and a miniaturized camera, producing readings at frame rate. An Extended Kalman filter is used to track the range data and detect environmental features of interest.

[1]  Jitendra Malik,et al.  Robust computation of optical flow in a multi-scale differential framework , 2005, International Journal of Computer Vision.

[2]  R. Welsh.  Foundations of Orientation and Mobility , 1979 .

[3]  D. Gebre-Egziabher,et al.  A gyro-free quaternion-based attitude determination system suitable for implementation using low cost sensors , 2000, IEEE 2000. Position Location and Navigation Symposium (Cat. No.00CH37062).

[4]  Allen Gersho,et al.  Vector quantization and signal compression , 1991, The Kluwer international series in engineering and computer science.

[5]  Martin David Adams,et al.  On-line gradient based surface discontinuity detection for outdoor scanning range sensors , 2001, Proceedings 2001 IEEE/RSJ International Conference on Intelligent Robots and Systems. Expanding the Societal Role of Robotics in the the Next Millennium (Cat. No.01CH37180).

[6]  Gaurav S. Sukhatme,et al.  Sensor fault detection and identification in a mobile robot , 1998, Proceedings. 1998 IEEE/RSJ International Conference on Intelligent Robots and Systems. Innovations in Theory, Practice and Applications (Cat. No.98CH36190).

[7]  L. Kay,et al.  A sonar aid to enhance spatial perception of the blind: engineering design and evaluation , 1974 .

[8]  Peter B. L. Meijer,et al.  An experimental system for auditory image representations , 1992, IEEE Transactions on Biomedical Engineering.

[9]  Martin Adams,et al.  Tracking Naturally Occurring Indoor Features in 2-D and 3-D with Lidar Range/ Amplitude Data , 1998, Int. J. Robotics Res..

[10]  J. Gibson.  The Ecological Approach to Visual Perception , 1979 .

[11]  American Foundation for the Blind , 1967 .

[12]  C I Howarth,et al.  The effect of non-visual preview upon the walking speed of visually impaired people. , 1986, Ergonomics.

[13]  D. Magill.  Optimal adaptive estimation of sampled stochastic processes , 1965 .

[14]  A D Heyes,et al.  An application of bio-feedback in the rehabilitation of the blind. , 1980, Applied ergonomics.

[15]  P. D. de Groen.  An Introduction to Total Least Squares , 1996 .

[16]  Robert S. Wall,et al.  Biomechanical Substrates of the Two-point Touch Cane Technique: A Review of Research , 2002 .

[17]  D. Bolgiano,et al.  A laser cane for the blind , 1967 .

[18]  C. Thorpe,et al.  Eye-safe laser line striper for outside use , 2002, Intelligent Vehicle Symposium, 2002. IEEE.

[19]  Y. Bar-Shalom.  Tracking and data association , 1988 .

[20]  Bernhard P. Wrobel,et al.  Multiple View Geometry in Computer Vision , 2001 .

[21]  Iwan Ulrich,et al.  The GuideCane-applying mobile robot technologies to assist the visually impaired , 2001, IEEE Trans. Syst. Man Cybern. Part A.