Secret Knock Door Opener
I. PROJECT OVERVIEW
Last semester, the “Spoiler Alert” developed a mechanism to open a door using only a rhythmic sequence. To extend this
poject, and make it more difficult, a new technique must be developed: Voice Recognition. The merit for this project is that I
occasionally find myself outside my (locked) front door, but without the key. Help me open my door by sensing when I knock
on it with a “teachable” pattern.
II. PROJECT DIAGRAM
Speak a Code
Phrase, or say
a vowel
Anayze and
compare to
preset
Actuate Door
release
III. REQUIREMENTS
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Develop a system that can distinguish a specific entity using voice pattern security
System must be able to work at varying tempos and pitches within a specific range.
The method of actuation should be user programmable.
Illuminate an LED upon successful passcode recognition
IV. MIDTERM DEMONSTRATION GRADING
Points
20
30
60
110
Requirement
Microcontroller can identify peak frequencies in the segment of
speech using a DFFT
Microcontroller can sample and store a 1 second segment of speech
Microphone circuit can recognize in the speech range with filters to
remove sounds outside the range of normal speech
Total Points
V. FINAL DESIGN PRESENTATION GRADING
Points
10
20
20
60
110
Requirement
Project cost kept under $150.
Other group members or the professor cannot open the door using
the same password (password uniquely identifies voice pattern)
A new password can be stored by another group member or the
professor and it will open, even when spoken in a different
manner.
One group member can uniquely open the door using a password
Total Points
VI. PROJECT POINTERS
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Each human voice has a unique pattern. Determine the best way to identify this pattern first
The discreet Fourier transform has advantages and disadvantages. It may be useful to sample higher than you need
for more accuracy of the transform.
Many of the problems may be in the programming. Be sure you have someone capable of thinking algorithmically
for this project.
Other student-engineers have created similar projects. It is acceptable to use others’ information; just be sure to
credit your sources.