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## The detection of walls and corners using acoustic methods

### Olga Magdalena Krawczyk

#### Abstract

The aim of this study was to develop the method used for detection of walls and corners with the use of acoustic signals. The presented system has been entirely developed in MATLAB environment, applying the knowledge concerning wave propagation, analytic geometry and signals processing. The development of the system can be divided into two stages. The aim of the ﬁrst stage was to deﬁne the criteria enabling the distinction between walls and corners. The following objects were modeled in MATLAB environment: a wall and a corner, as well as the spots where the transmitter and eight signals receivers were located. The ultrasound signal with the frequency of 20-22 kHz was generated from the loudspeaker. After being reﬂected from an obstacle, ultrasound signals are accompanied by various phenomena typical for sound waves. The reﬂected signals returning to the receivers from an obstacle are weaker. They cover the distance from transmitter to receiver in a certain time, which can be easily measured. Based on transmitted and returning signals analysis the delays of the signal were determined. Those delays were further compared to the delays resulting from the shortest distance between microphone matrix, loudspeakers and examined obstacle. The next stage focuses of the development of the algorithm aimed at determining if the signal received by the microphone had been reﬂected from a wall or a corner. The elements of analytic geometry, e.g. plane equation were used for the development of the algorithm. To carry the experiments, which would be the closest to the real-life situations, Gaussian noise was added to the received signal. The experiments were conducted for ﬁfty diﬀerent walls and corners generated separately for each of signal-to-noise ratio values. Based on the conducted experiments the percent relation of the obstacle detection eﬃcacy from the signal-to-noise ratio was determined.
Diploma type
Engineer's / Bachelor of Science
Diploma type
Engineer's thesis
Author
Olga Magdalena Krawczyk (FEIT/IRMT) Olga Magdalena Krawczyk,, The Institute of Radioelectronics and Multimedia Technology (FEIT/IRMT)Faculty of Electronics and Information Technology (FEIT)
Title in Polish
Detekcja ścian i naroży metodami akustycznymi
Supervisor
Marek Wojciech Rupniewski (FEIT/PE) Marek Wojciech Rupniewski,, The Institute of Electronic Systems (FEIT/PE)Faculty of Electronics and Information Technology (FEIT)
Certifying unit
Faculty of Electronics and Information Technology (FEIT)
Affiliation unit
The Institute of Radioelectronics and Multimedia Technology (FEIT/IRMT)
Study subject / specialization
, Inżynieria Biomedyczna (Biomedical Engineering)
Language
(pl) Polish
Status
Finished
Defense Date
13-02-2019
Issue date (year)
2019
Reviewers
Grzegorz Domański (FEIT/IRMT) Grzegorz Domański,, The Institute of Radioelectronics and Multimedia Technology (FEIT/IRMT)Faculty of Electronics and Information Technology (FEIT) Marek Wojciech Rupniewski (FEIT/PE) Marek Wojciech Rupniewski,, The Institute of Electronic Systems (FEIT/PE)Faculty of Electronics and Information Technology (FEIT)
Keywords in Polish
Detekcja kształtu przeszkód, sygnały akustyczne, ultradźwięki
Keywords in English
Shape recognition, acoustic signals, ultrasound
Abstract in Polish
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• File: 1
Praca_dyplomowa.pdf
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Local fields
Identyfikator pracy APD: 32224

Uniform Resource Identifier
https://repo.pw.edu.pl/info/bachelor/WUTfcfbfb9cc1674ed7a8343345a445b93c/
URN
urn:pw-repo:WUTfcfbfb9cc1674ed7a8343345a445b93c

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