Download Slide 1

Physiologic Metronome
Team Members: Ben Fleming, Cole Drifka, and Jeff Theisen
Clients: Dr. Bill Fahl and Vanessa Young
Advisor: Prof. Paul Thompson
Abstract
Final Design
Testing
Our group set out to design a metronome which uses a tactile
pulse instead of an aural stimulus to provide rhythmic
information to the practicing musician. The idea came from our
client, Vanessa Young, a harp player and current graduate student
at Carnegie Mellon University. The final design consists of an
electronic metronome that outputs to a solenoid which delivers
the tactile stimulus via an ear attachment. Testing demonstrated
sufficient battery life and relatively accurate tempo indication.
Figure 3 Output voltage versus time with the potentiometer set at (a) 100 beats per
minute (actual tempo: 99.8 bpm); (b) 60 bpm (58.1 bpm); and (c) 40 bpm (38.0 bpm)
Background
•A metronome is a device that provides a regular tempo
for playing a musical piece [1]
• The first mechanical metronome was patented by
Johann Malzel in 1816 [1]
• Modern metronomes are mostly electronic and typically
use a small speaker to produce a constant, audible sound
to maintain the tempo
Figure 1 The final prototype of the metronome. Both the
case and the solenoid-containing ear attachment are shown.
• Battery Life: Using a standard 9V battery, the circuit
was connected and ran continuously at the highest
tempo setting for approximately 16 hours.
• Accuracy and Reliability: The metronome appears to
give fairly accurate tempo outputs. Based on the tick
mark/potentiometer scheme, the output appeared to be
accurate within 2-3 beats per minute (Figure 3).
Motivation
Problems with existing devices (i.e. conventional,
audible metronomes):
• Using an audible tempo-maintenance mechanism,
such as a small speaker, can make it difficult to
distinguish the speaker’s sound from the music being
played
• Most conventional metronomes do not employ tactile
stimuli to maintain the tempo, while such tactile
stimuli facilitate the internalization of the rhythm for
the musician while she plays her instrument
Client Requirements
• An essentially inaudible tempo-maintaining
mechanism is to be employed in the metronome device
• The metronome device should be portable
• Accurate and reliable maintenance of the tempo by the
metronome device
• $100 budget
Future Work
Figure 2 The final circuit schematic. Adapted from [2].
Key Features of the Final Design (Figure 1):
• The case, which contains the perf-board-mounted
circuit (Figure 2)
• The knob/potentiometer, which protrudes from
the case and is used to adjust the tempo
• The tick marks, which indicate the selected tempo
• The ear attachment/solenoid, which delivers a
nearly inaudible, concise tactile stimulus to the
user
Total Cost: $61.57
• Further testing of the device by practicing musicians
• Digital display of the selected tempo (in lieu of tick
marks)
• Using buttons to select the tempo instead of a
knob/potentiometer
• Improve accuracy of tempo settings
• Possible multiple-metronome synchronization system
References
[1] Metronome. (2009). In Columbia Electronic Encyclopedia. Retrieved from
http://www.encyclopedia.com/topic/metronome.aspx
[2] Metronome circuit schematic. (2009). Electronic circuits.
http://electroschematics.com/216/electronic-metronome-circuit-schematic/