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Automatic Page Turner demo
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Automatic Music Stand Page Turner
By Group 6:
Jee Gun Kim
Rex Lu Robert Carlo Millan
Alvin Tai
Prepared for:
Professor Ken Youssefi ME130, Design of Planar Machinery May 9, 2006
ME 130: Design of Planar Machinery Spring 2006
Group 6 Automatic Page Turner
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Background Professional and amateur alike, most musicians have experienced reading sheet
music that typically span several pages and are usually in some type of bound form. Thus, in order for smooth transitions between pages, musicians need a method to turn a page without interfering with their performance. This is usually done with the
help of a page-turning assistant. However, for most musicians an assistant may not always be readily available. A mechanism mounted directly on the music stand that turns the page at the push of a foot-operated button will render the assistant unnecessary and obsolete.
Task Assignment
Group Member Task Jee Gun Kim • Initial design of mechanism
• Mechanism synthesis
• Acquire music stand • Kinematics analysis of design • Write written project
• Work on poster
Rex Lu • Draft design by hand • Acquire material for links
• Attach motor to the mechanism
• Machine the mechanism • Assemble the mechanism
• Work on poster
Robert Millan • Machine the mechanism
• Acquire motor and wood
• Cut plywood • Assemble the mechanism
• Make the poster presentation
Alvin Tai • Initial design of mechanism • Create 2D drawings using AutoCAD • Create 3D drawings using SolidWorks
• Acquire material used to lift page
• Machine the mechanism • Write written project
• Work on poster
List of Specifications/Requirements
The following is a list of specific design criteria that we tried to accomplish with our mechanism. These specifications and requirements were created in the beginning of
the project and our conceptual designs were developed to achieve these goals.
For final product:
• Non-distracting quiet and fast operation • High reliability, to prevent malfunction during performance
ME 130: Design of Planar Machinery Spring 2006
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• Compact design • Detachable from stand
• Battery operated
• One page turn per pedal depression For this project:
• Confirm functionality of design • Turn a page in a book of music notes • Turn several pages in succession • Not all final product functional requirements may be met
Conceptual Designs The main concern with creating an automatic page-turner was the mechanical ability to distinguish individual pages. Without any sort of electronic technology there were
only a limited number of ways to do this. Here are a couple of aspects that we
discussed during our brainstorming session (Appendix):
• Vacuum suction
• Magnetic attraction • Surface Roller • Surface Friction contact
Vacuum suction The idea behind a vacuum suction is that it would effectively separate the top page
from the rest of the book. The disadvantage to this type of method is that it would create unnecessary noise that would interrupt a musical performance. It would also
need to be incorporated into the 4-bar mechanism and integration would be difficult to implement.
Magnetic Attraction For this concept, we thought that we could attract individual pages off the bound
book and then create a turning device based on the magnetic attraction. The advantage to this concept would be the ability to move pages without physical
contact with the page. However, this turned out to be a difficult quality to control as
it was still difficult for the magnet to distinguish between the pages. Another disadvantage was the necessity to “prep” the music book with magnetic materials.
This was decided to be an impractical design.
Surface Roller This was a concept based on many inkjet printers out on the market. With a rubber
roller, a printer can effectively remove a single sheet of paper. Even without a 4-bar
mechanism, this would work well. However, unlike a printer, our device cannot cover a certain amount of space since allowing full visual contact with the sheet music is crucial for a musician; a roller would block too much space on the book.
Surface Friction Contact Our final conceptual design worked perfectly with the class requirements and the
necessary movement. The idea behind this was that we would have two main parts
of the mechanism. A rocker would lift a single page with a high-friction material (much like rubberized finger turners) while the crank would sweep underneath the lifted page for a complete page-turn. This acts similarly to the mechanism and
ME 130: Design of Planar Machinery Spring 2006
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motion of a windshield wiper; on a car, one arm acts to collect the water and the other arm sweeps the collected water off of the windshield. We developed two
designs for this concept: one that would work from the bottom and one that would
work form the top. We decided to design the former due to the limitations of the musical stand that we were working on. It was easier to attach a mechanism at the top rather than the bottom due to the protruding lip that the music book rests on.
Introduction
Our automatic page-turner uses a 4-bar mechanism as the foundation of the design. To create a mechanism that would turn a single page in a music book requires first distinguishing the pages within the book. The completed mechanism consists of two
main parts: a rocker that initially lifts a single page and a crank that finishes the entire page turn. To lift a single page, the rocker has a substance called “Paper Tak” which creates a high friction surface for effective page lifting. Because the majority
of musical instruments are played with the hands, we added a foot pedal that would
allow uninterrupted page transitions.
Detail Design The mechanism is a Grashof crank-rocker designed using a two position synthesis of
a four-bar crank and rocker to give 68 degrees rocker rotation with equal time
forward and back, from a constant speed motor input. The 68 degrees came from first, determining the horizontal distance between O2 and O4 as 7 inches, and then
trying to lower the position of O4 as much as possible. Figure XXX below shows the extreme right position of the rocker arm.
ME 130: Design of Planar Machinery Spring 2006
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Figure 1. Synthesis of the mechanism.
The velocity analysis was done at an arbitrary position of the mechanism using the
velocity polygon method. Since the angular velocity of link 2 was not available
during the time of the analysis, the other angular velocities and the velocities of the joints were found in terms of the angular velocity of link 2.
ME 130: Design of Planar Machinery Spring 2006
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Figure 2. Velocity analysis at an arbitrary position.
Drawings
Refer to appendix.
Bill of Materials
Item Quantity Description of Use
Cost
Manhasset Music
Stand
1 Stable base for
mechanism
$32.49
1/8” by 3/4” by 8’ aluminum
1 Material for linkages
$30.99
3/8” Plywood, 10” by 10” square
1 Base for motor and linkages, mounts to stand
$0.00
4” by 4” by 10” wooden beam
1 Material for offset wedge and blocks
in pedal
$0.00
Electric motor 1 Drives the crank $0.00
2” diameter 1 Link 2, connects to $0.00
ME 130: Design of Planar Machinery Spring 2006
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aluminum rod, 3”
long
motor shaft
Paper Tack 1 Adhesive used to pick up page
$4.00
3” door hinge 1 Hinge in foot pedal $4.55
Battery Holder 1 Holds AA batteries for easy wiring
$0.00
AA batteries 4 Power for the motor
$0.00
Mini Breadboard 1 Mount for resistors $0.00
10 ohm Resistor 3 Varies the speed of
the motor
$0.00
Compression Springs
5 Provides counter force in pedal,
mount for paper tack
$0.00
Total $72.03
Discussion & Future Modifications
During the design phase of our mechanism, we encountered a couple problems that
ultimately led to our final design. The following is a summary of the problems and solutions that were developed during the design of this device:
• Offset plane: We noticed that with a crank and rocker operating on the same plane as the music book created a problem. If the sweeping page-turning arm (crank) were to be on the same plane as the book, it would
eventually hit the book binding rather than sweep a single page. This also
proved to be a difficult problem to solve since we weren’t qualified to design 3-dimensional mechanisms. We finally decided to create an angled wedge (Figure 3) that would offset the operational mechanical plane. This would
allow the rocker to maintain physical contact with the page while permitting the crank to sweep individual pages.
• Maintaining rocker contact: Because the mechanical plane is slightly offset,
we wanted to have the rocker to stay in contact with the page for as long as possible. We initially designed a spring-loaded rocker that would force the
arm to maintain physical contact with the page for as long as possible.
However, this was unnecessary as we eventually developed a simplified version that was just as effective, as seen in Figure 3.
Spring Loaded
Rocker
ME 130: Design of Planar Machinery Spring 2006
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(a) (b) Figure 3. (a) Initial design for rocker (b) Final design.
• Creating Frictional Contact: The initial design called for a simple eraser to
create a high-friction surface to lift single pages off of the music book. After
several tests with an ordinary notebook, we believed that this would be sufficient. However, when we finally acquired the actual music book that we were going to use, we noticed that there was a flaw in our design. A music
book has very different physical qualities compared to a normal notebook.
The music book has thicker and smoother pages which increases the force needed to separate pages. We began to research different chemical adhesives that would allow continuous reuse without affecting the frictional coefficient
that we needed; some technologies that we looked into included Post-It Notes and masking tapes. We finally found a substance called “Paper- Tak” that is used to hang/hold delicate pictures without damaging the photos. These were
reusable and maintained a high-friction surface for our design.
• Motor Speed: Our final problem arose with our electric motor that we used
drive the crank. We overestimated the speed of our initial motor and the mechanism failed to lift the page. This occurred because with a higher speed,
the adhesive (Paper-Tak) wasn’t able to “grab” the page from the music book. The kinetic friction was too small to pick up the page, and the speed of the
motor didn’t allow us to operate in the static friction region. This was an
unforeseen problem and the design had to be modified with a lower RPM motor that could provide more torque.
Future Modifications There are two aspects of our current design that can be modified in the future to
increase the effectiveness of the automatic page-turner. It would be beneficial to find a solution to minimize the noise created by the mechanism since it will probably be used during musical performances. This can probably be achieved with a more
expensive motor and insulation around the linkages. We do not have the resources to obtain another motor so it was difficult to change this aspect of our design. The linkages also produce noise as they collide with each other during the mechanical movement. This can be minimized by using insulation to prevent contact between
the bars. Another important aspect of the design is the aesthetics of the device. The design
should not be visually disturbing or distracting since it will be mounted on a musical stand. A musician must focus on the composition rather than the sudden movement of this device. In the future, we want this device to become part of the music stand
rather than an accessory. With the right aesthetic design, we can create a less
distracting method of turning pages.
Page contact force
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References Norton, R. Design of Machinery: An Introduction To The Synthesis and Analysis of Mechanisms and Machines. Third Edition New York: McGraw Hill. 2004. Youssefi, K. ME130: Design of Planar Machinery Notes. www.me.berkeley.edu/ME130. Retrieved from the World Wide Web on May 08, 2006.
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Appendix
Hand sketches and conceptual designs
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