IFE – Mechanical Engineering

IFE – Biomedical Engineering

IFE – Pattern Recognition

Stereophonic representation of virtual 3D scenes - a simulated mobility aid for the blind

Author: Michał Bujacz MSc

Supervisor: Associate Professor Paweł Strumiłło Msc PhD DSc

The thesis won the competition for the best MSc thesis in the academic year 2004/2005 organized by the Polish Association of Electric Engineers (SEP) and the Faculty of Electrical, Electronic, Computer and Control Engineering of the Technical University of Lodz.

Author: Michał Bujacz

The goal of the thesis was to design a method of describing 3D scenes using auditory output that could be used in an electronic travel aid (ETA) for the blind, which was being developed at the Institute of Medical Electronics. The method was implemented in a simulation program that could both demonstrate it and test its effectiveness. The thesis was written by Michał Bujacz under the supervision of Professor Paweł Strumiłło.

The task was approached through an extensive literature search concerning blindness, especially the perception of spatial relations by the blind, existing ETA devices, human perception of sound, the process of its localization, and generation of virtual sound sources. In parallel to that search, a simulation program was created, that allowed users to move about in virtual 3D scenes generated using OpenGL.

The designed auditory space representation methods, also referred to as the "sound codes", based on the concept of representing range through sound frequency. The nearer a scene element was to the user, the higher pitched sound it produced. A number of auditory space representation methods were created, differing in the way the environment was scanned for obstacles.

The completed simulation program was tested by 10 sighted volunteer who were individually trained for 2-3 hours and then asked to complete a few experimental trials, in which they drew scenes presented to them via the sound code, or maneuvered between unseen obstacles. The research results will be used in the design of an ETA at the Department of Medical Electronics.

The SEP competition is organized yearly and awards master's theses that concern innovative subjects, produce useful research results, show that a lot of work and literature research was put in by the authors. The second place in this years contest was for the thesis of Przemysław Ignaciuk "ABR service flow control in ATM networks". The third place was awarded to Jakub Mielczarek for "Design of a digital communication circuit, highly resistant to radiation".