6 axis robot arm

151 Pages·2013·2.3 MB·English

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University of Southern Queensland
Faculty of Health, Engineering & Sciences

Make Garfield (6 axis robot arm) Smart
through the design and implementation of
Voice Recognition and Control

A dissertation submitted by
Kyle Tonkin
in fulfilment of the requirements of
Course ENG4111 Research Project part 1 & ENG4112
Research Project part 2

Towards the degree of
Bachelor of Electrical Engineering

Submitted: October, 2013
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ABSTRACT

The Voice is a powerful tool used in everyday life. It expresses our feelings, emotions and is
unique to every individual. Developing a system to decipher its functionality and deal with the
complexities involved in its digitalisation, becomes quite the task. Once harnessed, it has the
potential to become one of the most popular methods of control throughout the world.
Garfield (a 6 axis robotic arm) is in need of an extra method of control that can essentially
make it ‘smarter’. In trend with current popularity, Voice Recognition has been selected as the
method for control and the processes taken to implement such a system are explored in the
following dissertation. Its outlines the design, development and implementation of a working
voice recognition system used in conjunction with robotic arm software. In essence, this
project explores the application of such a technology to the industrial robot industry and tests
its performance as a whole.
A signal processing methodology was investigated, designed and developed in order to
implement the voice as a control tool on the robotic system. This included the research and
development of a voice detection algorithm based on the principles of voice recognition and
required integration with robotic control software to execute appropriate movement.
Existing literature was explored in order to understand and apply the concepts of voice
recognition and integrate it into a system responsive to user utterances. The basic outline of
the processing techniques used followed those involved with Mel Frequency Cepstral
Coefficients (Kumar & Rao 2011) and the recognition techniques involved with Euclidean
distances (Muda, Begam & Elamvazuthi 2010). In applying these techniques within the Matlab
platform, some Voice Processing tools (Brookes 1998) were sort out and used. A number of
final design parameters were evaluated and tested in order provide recommendation to
further system users and set objectives for future work.
The results of system performance testing discovered that jogging the system via the voice
controlled method was viable with further improvement to the system response and quality
of the control algorithm. Furthermore, possible solutions to the blemishes in the system are
explored and avenues for further research and development stated.
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University of Southern Queensland
Faculty of Health, Engineering & Sciences

ENG4111 Research Project Part 1 &
ENG4112 Research Project Part 2

Limitations of Use
The Council of the University of Southern Queensland, its Faculty of Health,
Engineering and Sciences, and the staff of the University of Southern Queensland, do
not accept any responsibility for the truth, accuracy or completeness of material
contained within or associated with this dissertation.
Persons using all or any part of this material do so at their own risk, and not at the risk
of the Council of the University of Southern Queensland, its Faculty of Health,
Engineering and Sciences or the staff of the University of Southern Queensland.
This dissertation reports an educational exercise and has no purpose or validity
beyond this exercise. The sole purpose of the course pair entitled “Research Project”
is to contribute to the overall education within the student's chosen degree program.
This document, the associated hardware, software, drawings, and other material set
out in the associated appendices should not be used for any other purpose: if they are
so used, it is entirely at the risk of the user.
Professor Frank Bullen
Dean
Faculty of Health, Engineering and Sciences
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CERTIFICATION

I certify that the ideas, designs and experimental work, results, analyses and
conclusions set out in this dissertation are entirely my own effort, except where
otherwise indicated and acknowledged.

I further certify that the work is original and has not been previously submitted for
assessment in any other course or institution, except where specifically stated.

Student Name: Kyle James Tonkin

Student Number: 0061005209

____________________________
Signature

____________________________
Date
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ACKNOWLEDGEMENTS

I would firstly like to acknowledge the support and advice given to me by my
supervisor, Dr Tobias Low. Without his presence, I would not have been able to
progress through the year and submit my final dissertation. His knowledge and skills
have been flawless, helping me through all of the problems I have faced.
I would also like to thank my family and friends, who have been there for me
throughout the year and supported everything I have done. Hopefully they will remain
there for me as I progress into the future. Thank you.
KYLE
TONKIN
University of Southern Queensland
October 2013
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Contents

ABSTRACT ...................................................................................................................................... ii
CERTIFICATION ............................................................................................................................. iv
ACKNOWLEDGEMENTS ................................................................................................................. v
List of Figures ................................................................................................................................ x
List of Tables ................................................................................................................................ xi
Nomenclature ............................................................................................................................ xiii
Robotic Voice Recognition and Control ....................................................................................... 1
1.1 Introduction ....................................................................................................................... 1
1.2 Project Aim ......................................................................................................................... 4
1.3 Project Objectives .............................................................................................................. 5
1.4 Overview of Dissertation ................................................................................................... 6
Literature Review ......................................................................................................................... 7
2.1 Chapter Overview .............................................................................................................. 7
2.2 The concept of Speech ....................................................................................................... 8
2.3 Speech Processing .............................................................................................................. 9
2.3.1 Sampling .................................................................................................................... 10
2.3.2 Pre-emphasis ............................................................................................................. 10
2.3.3 Framing ..................................................................................................................... 11
2.3.4 Hamming Window .................................................................................................... 11
2.3.5 Discrete Fourier Transform ....................................................................................... 12
2.3.6 Mel Frequency Scale and FilterBank ......................................................................... 13
2.3.7 Mel Frequency Coefficients ...................................................................................... 14
2.3.8 Hidden Markov Model (HMM).................................................................................. 15
2.3.9 Dynamic Time Warping (DTW) .................................................................................. 15
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2.3.10 Artificial Neural Network (ANN).............................................................................. 16
2.3.11 Vector Quantisation (VQ) ........................................................................................ 16
2.4 Speech as a form of control ............................................................................................. 17
2.5 The 6 axis Robot arm ....................................................................................................... 18
2.5.1 History ....................................................................................................................... 18
2.5.2 RobotStudio .............................................................................................................. 20
2.5.3 RobotStudio Coding (RAPID) ..................................................................................... 21
2.5.4 Previous Industrial Application ................................................................................. 23
2.6 Communication Link (TCP/IP) .......................................................................................... 23
2.7 Chapter Summary ............................................................................................................ 25
Methodology .............................................................................................................................. 26
3.1 Chapter Overview ............................................................................................................ 26
3.2 Research and Development Methodology ...................................................................... 27
3.3 Task Analysis .................................................................................................................... 28
3.3.1 Hardware and Software identification ...................................................................... 29
3.3.2 Voice Recognition Algorithm .................................................................................... 29
3.3.3 Robotic arm Coding ................................................................................................... 31
3.3.4 Communication Link ................................................................................................. 32
3.3.5 Testing and Evaluation .............................................................................................. 32
3.4 Consequential Effects ...................................................................................................... 33
3.4.1 Sustainability ............................................................................................................. 33
3.4.2 Safety ........................................................................................................................ 34
3.4.3 Ethical Considerations ............................................................................................... 35
3.5 Risk Assessment ............................................................................................................... 35
3.6 Research Timeline ............................................................................................................ 36
3.7 Chapter Summary ............................................................................................................ 36
Design & Implementation .......................................................................................................... 37
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4.1 Chapter Overview ............................................................................................................ 37
4.2 Voice Recognition Methodology ...................................................................................... 37
4.2.1 Pre-Emphasis ............................................................................................................. 38
4.2.2 Silence Detection and Data Reduction ..................................................................... 40
4.2.3 Framing and Windowing ........................................................................................... 43
4.2.4 Discrete Fourier Transform ....................................................................................... 45
4.2.5 Periodogram based Power Spectral Density (PSD) estimate .................................... 46
4.2.6 Mel Filter Bank .......................................................................................................... 46
4.2.7 Log filter bank energies and Discrete Cosine Transform .......................................... 47
4.2.8 Model Building .......................................................................................................... 47
4.2.9 Recognition using Euclidean Distance ...................................................................... 49
4.3 Command Action Methodology ....................................................................................... 50
4.3.1 Command Structure .................................................................................................. 50
4.3.2 Building Commands .................................................................................................. 52
4.3.3 Command Execution ................................................................................................. 56
4.4 Interfacing and Communication ...................................................................................... 57
4.5 Chapter Summary ............................................................................................................ 60
Performance and Evaluation...................................................................................................... 61
5.1 Chapter Overview ............................................................................................................ 61
5.2 Performance Methodology .............................................................................................. 62
5.3 Error rate Performance .................................................................................................... 63
5.3.1 Methodology ............................................................................................................. 63
5.3.2 Measurement and Testing ........................................................................................ 64
5.3.3 Discussion of Results ................................................................................................. 69
5.4 Command Usability (Quantitative) .................................................................................. 72
5.4.1 Methodology ............................................................................................................. 72
5.4.2 Measurement and Testing ........................................................................................ 73
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5.4.3 Discussion of Results ................................................................................................. 77
5.5 Real time algorithm and communication response ......................................................... 78
5.5.1 Response Methodology and Results ......................................................................... 78
5.5.2 Discussion of Results ................................................................................................. 82
5.6 Qualitative Analysis of Results ......................................................................................... 83
5.6.1 Ease of Use ................................................................................................................ 83
5.6.2 Industrial Application ................................................................................................ 86
5.6.3 Constraints ................................................................................................................ 87
5.7 Chapter Summary ............................................................................................................ 87
Conclusions & Further work ...................................................................................................... 88
6.1 Chapter Overview ............................................................................................................ 88
6.2 Conclusions ...................................................................................................................... 88
6.3 Further Work .................................................................................................................... 90
References ................................................................................................................................. 91
Appendix A ................................................................................................................................. 93
Appendix B ................................................................................................................................. 95
Appendix C ............................................................................................................................... 101
Appendix D ............................................................................................................................... 102
Appendix E ............................................................................................................................... 138
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List of Figures
Figure 1 - ABB 6 axis Robot Arm .................................................................................................. 3
Figure 2 - Mel Frequency Scale .................................................................................................. 13
Figure 3 - Triangular Spaced Filters ............................................................................................ 14
Figure 4 - Module annotation .................................................................................................... 21
Figure 5 – RAPID program Layout .............................................................................................. 22
Figure 6 - System Block Diagram ................................................................................................ 28
Figure 7 - Simple Process Diagram ............................................................................................. 30
Figure 8 - Speech Signal of Command 'ONE' .............................................................................. 38
Figure 9 - Command "ONE" Pre-emphasised............................................................................. 39
Figure 10 - Silence Detection Code ............................................................................................ 40
Figure 11 - Data Reduction ........................................................................................................ 41
Figure 12 - Command 'ONE' after silence detection .................................................................. 42
Figure 13 - Framing Diagram ...................................................................................................... 43
Figure 14 - Hamming Window ................................................................................................... 44
Figure 15 - Hamming Window applied to the frame ................................................................. 44
Figure 16- Mel Filter Bank (Lyons 2009) .................................................................................... 46
Figure 17- Model Diagram of utterance ‘One1’ ......................................................................... 47
Figure 18- Command Model 'ONE' ............................................................................................ 48
Figure 19 - Command-Action number pad ................................................................................ 50
Figure 20 - Initial Robot Position ................................................................................................ 52
Figure 21 - Axis 3 movement ..................................................................................................... 52
Figure 22 - Axis 2 movement ..................................................................................................... 53
Figure 23 - Axis 4 movement ..................................................................................................... 53
Figure 24 - Axis 1 movement ..................................................................................................... 54
Figure 25 - RAPID code for Higher command ............................................................................ 55
Figure 26 - RAPID code for Lower command ............................................................................. 56