Tactile Display
Binyam Gemeda
Kalung Ma
University of Massachusetts Boston
Electrical Engineering Department
Project Pre-Proposal
Abstract
A static tactile display design and implementation is presented in this report. The tactile display
will have 360 by 360 mm dimension and holds 10x10 PLA filaments. The filament’s linear
motion is controlled by NMB 25-stepper motor. The motors are controlled and driven by
Atmega32 and stepper motor driver A4498/SP. The hex file to program the Atmega IC is written
in Atmel Studio6. Xeltek SuperPro M universal device programmer will implement the program.
The body of the tactile display is thermoplastic polymer such as PLA or ABS that is used for the
3D printer. The display will be equipped with audio output to provide more information for the
user.
Table of Contents
1. Introduction ............................................................................................................................. 1
2. Background .............................................................................................................................. 1
2.1 Electrical Tactile ................................................................................................................. 1
2.2 Vibro-Mechanical Tactile ..................................................................................................... 2
2.2.1 Electro-Mechanical System ............................................................................................ 2
2.2.2 Pneumatic Tactile System .............................................................................................. 3
2.3 Static Low Frequency Tactile Displays ............................................................................... 3
3. Goals ....................................................................................................................................... 5
3.1. Portability ............................................................................................................................. 5
3.2. Power Efficiency .................................................................................................................... 5
3.3. Display Dimension ................................................................................................................. 5
4. Design ..................................................................................................................................... 5
4.1. Threaded Shaft and Micro Stepper Motor .................................................................................. 5
4.1.1. Threaded Shaft and Micro Stepper Motor ............................................................................... 6
4.2 Second Alternative Approach of Micro Stepper Motor ............................................................. 6
4.3 Filament ............................................................................................................................. 7
4.4 Sound Output ...................................................................................................................... 8
4.5 Touch Input ........................................................................................................................ 9
4.6 Application Software ..........................................................................................................11
5. Work Flow .........................................................................................................................11
6. Engineering Standards for Tactile displays ..................................................................................14
6.1. Guidance on Tactile and Haptic Interaction ..............................................................................15
7. Impacts ...................................................................................................................................17
7.1. Societal Concern ...................................................................................................................17
7.2. Ethical Concern ....................................................................................................................17
7.3. Environmental Concern .........................................................................................................17
7.4. Safety Concern .....................................................................................................................17
8. Team ......................................................................................................................................17
8.1. Team Member Responsibilities ...............................................................................................17
8.2. Team Organization ................................................................................................................18
8.3. Milestones ............................................................................................................................19
8.4. Budget .................................................................................................................................20
Bibliography ..............................................................................................................................21
1. Introduction
Any device, which senses information such as shape, texture, softness, temperature, vibration or
shear and normal forces, by physical contact or touch, can be termed a tactile sensor [1]. Since
the early 1970 several different types of tactile devices are introduced in an effort to minimize
power requirements and weight while simultaneously maximizing the stimulus effect [3].
However, Currently Tactile displays are poorly developed. According to Pasquero and Hayward
[2], Poor usability is the main reason for very slow development of tactile displays as currently
available displays are cumbersome, bulky and very expensive. On the other hand unlike sight
and sound, sense of touch is not localized and Difficult to imitate [4]. This may also be a
contributing factor for the slow growth of tactile displays. Despite slow growth, tactile device
can be used in teleportation and tele-presence, sensory substitution, 3D surface generation,
Braille system and games [6].
To help visually impaired persons in a society developing a better social cycle, integrated into
community and community activities, there are many technologies help them achieve these
thought access to visual text and graphics. This technology has auditory and tactile feedback
instead of vision. Auditory feedback is a voice screen reader to transfer information to speech,
such as illustration and diagrams. And the tactile feedback can demonstrate the spatial
information. Tesla Touch is a successful case of a touch sensitive screen with haptic feedback
[10].
2. Background
Tactile displays can generally be categorized as Electrical and Vibro-Mechanical. Other less
know tactile display technologies such as Static Low Frequency and Electro-Active Polymer are
also available [3].
2.1 Electrical Tactile
Electrical tactile system provides tactile stimulation by inducing electrical current through the
skin in a process known as electro-cutaneous stimulation [3]. “The electric field generated then
excites the neighboring afferent nerve fibers responsible for normal mechanical touch
sensations” McGrath, B., et al (2008). In this type of tactile display there is no mechanical part
that moves. As the result of this the electrical tactile displays are slimmer and light weighted than
mechanical tactile displays.
1
Fig 1. Extensor Electrical Tactile Stimulation System. (McGrath, B., et al (2008)).
2.2 Vibro-Mechanical Tactile
Vibro-Mechanical stimulation activates different types of mechanoreceptors in the skin [2].The
response of these receptors are largely dependent up on the frequency, amplitude, duration and
the total area of stimulation [2].The optimal frequency of human mechanoreceptors found to be
around 150 to 300 Hz [2].
2.2.1 Electro-Mechanical System
Vibro-Mechanical tactile can be categorized in to electro-mechanical and Pneumatic system.
Linear actuator and Rotary Inertial tactile system are electro-mechanical system [3]. The rotary
inertia types of tactile devices often found in pager motors of cell phones [3].
Linear actuators are coil based actuators that incorporate contactors that oscillate perpendicularly
when electric signals are applied [3]. This type of tactile devices designed with primary
resonance in the 200 to 300 Hz range, that peak sensitivity of the Pancinian corpuscles of the
skin [3]. Fig 2 shows C2 Tactor from Engineering Acoustic that deploys linear actuators.
Fig 2. C2 Tactor of Engineering Acoustic (McGrath, B., et al (2008)).
2
2.2.2 Pneumatic Tactile System
Pneumatic tactile devices use airflow to create vibration. “Oscillatory compressed air signals are
typically generated by sub-miniature solenoid valves connected to either a compressor or
pressurized air tank. An example is the Steadfast Technologies P2 tactor. The P2 tactor uses a
pressure of approximately 40PSI and a flow of 1 L/min” (McGrath, B., et al (2008)).
2.3 Static Low Frequency Tactile Displays
Pin-Based tactile displays, Hydraulic tactile and Piezo-Electric tactile devised are all categorized
under Static Low Frequency Tactile displays. Pin based tactile displays are composed of an array
of metallic pin arranged in a surface in square or hexagonal manner. The metallic pin forms
different patterns to transfer information. Optacon is well known Pin-based tactile display [3].
Fig 3. Optacon tactile display for the visually impaired (courtesy of http://www.dlfdata.org.uk).
University of Stuttgart, Visualization and Interactive System Institute develop Pin-base tactile
web browsing system for blind people [5].
Fig 4 Metec Display Tactile web browser (Rotard, Martin, Christiane Taras, and Thomas
Ertl (2008)).
3
The Hydraulic tactile display is very similar to the Pneumatic device except that it uses fluid
instead of air. Electro-Active Polymers and Micro-Electro-Mechanical systems consider as
technologies that are under development for future use. Electro-Active polymers contract and
expand in the presence of eclectic current [3]. Micro-Electro-Mechanical System (MEMS)
deploys sensors, actuators and mechanical devices on a common silicon substrate [3]. One type
of hydraulic tactile display is shown in Fig 5. The device is developed by Hull University
researchers [6].
Fig 5. 5x5 tactile display based on electro rheological fluid [6].
Researchers at University of Carnegie Mellon, Micro-electromechanical System Laboratory
developed a tactile interface chip based on MEMS technology [6]. The MEMS chip contains 24
actuators of different size on a surface of 1cm^2 [6].
Fig 6. Micro-Electro-Mechanical System (MEMS) [6].
The motivation for this project is to develop cheap and portable static tactile display by using
micro stepper motors. By only moving 10 stepper motors at a time and locking the filament at a
given position, the project also aim to significantly reduce the power needed to operate the
display.
By developing portable and affordable tactile display, individuals who have visual or/and
hearing disability will benefit immensely.
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3. Goals
3.1. Portability
The usability of tactile device can be significantly improved by making the device portable and
cheap. In this project, the standard linear actuator motors for static tactile display will not be used
as these motors are very expensive and drive the coast significantly higher. Mini stepper motors
are cheaper alternative. By constraining the circular motion in the X and Y axis of the shaft of
the micro-stepper motor, a linear motion in the y axis can be achieved. Since micro stepper
motors are very small in the range of 6mm to 15mm in diameter and 4mm to 10mm high,
employing these types of motors can significantly reduce the bulkiness of the tactile display.
3.2. Power Efficiency
The power consumption of micro stepper motors is very small. A typical micro stepper motor
with 30 ohm internal resistance requires 3 to 5V and about 0.1A current. To move 10 micro
stepper motor at a given time, 1 A current is needed.
3.3. Display Dimension
The Tactile display will have 10x10 arranged 100 filaments. The filaments are separated by
1mm.Each filament moves 0 to 75mm.The size of the display is expected to be 350mm by
350mm.Some modification may be applied depending on the final design of the display.
4. Design
4.1. Threaded Shaft and Micro Stepper Motor
Advancement in motor technology provides several alternatives to create linear motion. Motors
that provide accuracy in micrometers ranges are available in the market. The price tag per motor
however is very high. Single piezo linear actuator can cost more than hundred dollars. Since
several motors are needed, expensive actuators are not considered. Micro stepper motor such as
Sanyo or NMA 2phase bipolar stepper motor is selected. The motor provides 18-degree step
angle, which is 20 steps per 360 degrees.10 motors, cost about 20 dollars, as shown in Figure 7.
The motor comes with threaded shaft and small lock for linear motion. The housing of the tactile
display will be printed using 3D printer. The material of choice is PLA. If the motor heats too
much, ABS may be used.
5
Fig 7. 18-Degree Step Angle in Micro Stepper Motor
4.1.1. Threaded Shaft and Micro Stepper Motor
NMB 2 phase 4 wires stepper motor is considered for this design. The stepper motor needs 3 to 5
v. The stepper motors will then be coupled with threaded shaft on the blocks with PLA coupler
design and printed by the team.
Fig 11. NMB 2phase bipolar stepper motor.
4.2 Second Alternative Approach of Micro Stepper Motor
The team also comes up with a second alternative approach to the project. In this approach 4
6
NEMA 14 stepper motors are used. The housing that holds the single stepper motor that rotates
the threaded shafts moves in the XYZ direction by three NEMA 17 stepper motors which are
shown in Figure 12. To accomplish this, six linear ball bearings and shafts will be used. Timing
gear and Pinion pulleys are also needed. This approach requires a much more precise movement
of motors in the XYZ direction. The advantage of this system is that it only uses four motors.
However, the display would be expected to be bulkier and heavier and slower in this design
approach.
Fig 12. NEMA 17 stepper motor.
4.3 Filament
To gain higher filament altitude, the group also considered a different design approach. Filament
that have dimension of 14.5 x 14.5 mm and 72.5mm height is mounted on 6.32mm threaded
shaft. 25 shafts are mounted on 70x70 mm PLA bock as shown in Fig 8.
Fig 8. 5x5 filament assembly on PLA block.
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Four of such blocks will be assembled to form the 10x10 filament assembly as shown in Fig 9
and 10. Each filament's threaded shaft is driven by single stepper motor.
Fig 9. 10x10 Filament Assembly.
Fig 10. 10x10 filament top view.
4.4 Sound Output
Each filament will be equipped with small button that will inform the microcontroller its XYlocation on the display. The filament location will be used to give more information by providing
sound output. APR 9600/APR33A3 chip or other similar sound record and playback modules
such as ISD 1932 will be used to achieve this goal.
8
Fig 13. ISD 1932 sound record and playback module from spark fun.
Again, according to datasheet of ISD1932, the operating voltage (Vcc) is between 2.4V to 5.5V,
as shown in Figure 14. ISD1932 can provide 5.5V to each button when it is being used.
’
Fig 14. Operating Conditions of ISD 1932.
4.5 Touch Input
To create the touch input for the sound output, 100 buttons will be installed on the top of each
filament. What we have in the Tactile Display is 100 buttons and 10 signal lines, which contains
10 inputs and 10 outputs. The basic set-up is in a grid pattern where the 10 input lines come
down as 10 columns (pin 1 to pin 10), and the 10 output lines come across as rows (pin 11 to pin
20). Each column connects a 1k resistor. Every row, which can be regarded as an output,
connects to the Atmega32. The touch button serve as an input to the sound record and play back
module to inform the users what kind of things in the picture you are touching. It is shown in
figure 15.
9
Figure 15 – Draft of Schematic Diagram of Touch Sensor
Again, each button is a momentary on button, which means each button is normally open and is
in an open circuit. When a button is hit, it will make a connection between the button input and
output, and become a complete circuit. Otherwise, there is no connection.
To control the buttons, 5.5V can be supplied to the column and let the rows connection go to
multiplier and ISD 1932 sound record playback module. Choosing a correct resistor can protect
the buttons better. Since only one button in a column should be pressed at once, the size of
resistor can be calculated by using Ohm’s Law (V=I*R). According to the data sheet of button,
the switching current of absolute maximum is 50mA. It means the button allows 50mA current in
maximum to flow. Also, the switching voltage maximum is 42V DC, as shown in Figure 16.
Figure 16 - The Maximum Value of Switching Voltage and Current of Button
Therefore, when it is assumed to be max operating current and the voltage drop, 110Ω of resistor
can be allowing for the max current with 5.5V input.
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4.6 Application Software
Student from computer science department will develop the application software. If no student is
available to participate in this project, the help of an application developer will be considered.
For the application software, an image initially is converted in to depth map using software such
as Photoshop or Crazy Map. The images can be directly taken by camera that has capability to
take depth map. The pixels then divided in to 10x10 regions. The value of bite map of the depth
map is averaged for each square area. The value of the depth map of each pixel can be read by
Matlab image processing algorithm. A total of 100 depth map values that range from 0 to 1 is
generated. These values are sent to the micro-controller through standard communication
protocol. The micro-controller then uses the values to determine how many steps should each
stepper motors go.
5. Work Flow
For the first part of this project, it is 3D design, printing and assembling of the tactile display
components. Once the 3D printed filaments and threaded shafts are mounted on PLA block, the
blocks will be fitted in to stepper motor assembly blocks that hold NMB stepper motors with
PLA housing. Each functional unite blocks is fitted with buttons that will be used as input for the
sound record and play back module. Functional blocks then assembled to form the 10x10 tactile
displays.
Atemega32, H-Bridge or stepper motor driver module A4988/SP, Mux/DeMux (74HC4051) and
an array of transistor (2N7000) will be deployed to control stepper motors on functional blocks.
Another Atmega32, an array of tactile switch off momentary on single pole single throw input
button and ISD 1932 modules will be used to create button input and sound output features of the
tactile display.
Fig 16 Stepper motor driver A4988/SP, Atmega328P IC, SPST button ,2N7000 MOSFET, Xeltek
Superpro M.
Studio6 of Atmel will be used to program the Atmega IC chips. Once the hex files are generated,
universal devise programmer Xeltek SuperProM will be used to implement the hex files on the
IC chips.
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Fig 17. A microcontroller, decoder and two motors configuration (illustration only not actual
design).
Fig 17. Atmel Studio6 AVR programming software. Fig 18. Printrbot Simple Metal 3D printer.
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Fig 17. Flow chart of Tactile display.
Fig 18.Flow diagram of Tactile display.
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Fig 19. Work flow diagram for the application software.
6. Engineering Standards for Tactile displays
As tactile displays are becoming more and more versatile, engineering standards can ensure that
systems are designed with sufficient concerns for ergonomic and interoperability [7]. Ergonomic
standards provide better consistency and interoperability but also improve effectiveness and
avoid errors, improve performance and enhance the comfort and wellbeing of users [7]. Tactile
device usability and applicability’s are dependent up on multitude of variables. Some of the most
common performance measurement factors and variables according to McGrath, B., et al (2008)
are:
I. Magnitude – Peak-to-peak amplitude of the mechanical/electrical output signal;
II. Frequency – Number of cycles per second at which the tactor stimulus operates;
III. Waveform – Descriptive shape of stimulus pattern (e.g., sine wave, square wave, saw
tooth);
IV. Pattern – Set of ordered, repeating stimulations;
V. Duration – Time interval the tactor is active;
VI. Location – Position on the body where the tactor stimulates the tissue;
VII. Contactor Size – Surface area of the electrode or displacement (moving) portion of the
tactor; and
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VIII.
Interstimulus Interval – Time interval between the conclusion of one tactile
stimulation and the beginning of the next.
For tactile and haptic devices new set of standards are developed by International
Organization for Standards (ISO). “ both ISO and CEN standards, provide ergonomic
requirements and recommendations for haptic and tactile hardware and software interactions,
including guidance related to the design and evaluation of hardware, software, and
combinations of hardware and software interactions” Van Erp, Jan BF, et al(2010) as shown
below.
6.1. Guidance on Tactile and Haptic Interaction

Applicability considerations for haptic interactions, including: limits to effectiveness,
workload considerations (efficiency), user acceptance considerations (satisfaction),
workload considerations (efficiency), user acceptance considerations (satisfaction),
workload considerations (efficiency), user acceptance considerations
(satisfaction),and security and privacy [9].

Tactile/haptic inputs, outputs, and/or combinations, including: unimodal and
multimodal use of haptic interactions, intentional individualization, and unintentional
user perceptions.

Attributes of tactile/haptic encoding of information, including: using properties of
objects, using perceptual attributes, and combining attributes[9].

Content-specific encoding (what to encode), including: encoding and using textual
data, encoding and using graphical data, encoding subjective data, and encoding and
using controls [9].

Layout of tactile/haptic objects, including: resolution, separation, and consistency
[9].

Interaction, including: interaction tasks (such as navigation, selection, and
manipulation) and interaction techniques (such as moving objects, possessing
objects, and gesturing). Guidance for specific haptic interactions related to reading
tactile alphabets and notations suitable for blind or deafblind people are handled
byUnicode and other national standard [9].
ISO 9241 and TC159/SC4 provides detail guideline for Tactile/haptic interface [8].A general
guideline is also provided by . Carter, Jim, and David Fourney(2005) as shown below.

"Interaction should be natural, efficient, and appropriate for target users, domains,
and task goals." [16] [8]
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
The system should enable users to interact with and control their movement
throughout a virtual environment in a natural, streamlined fashion [16] [8].

The system should provide sufficient movement controls to support all aspects of the
task. [16] [8].

Where multimodal output is used, information presented in each modality should be
readily understood, unambiguous, and necessary to complete the task. [16] [8].

Where the task allows, haptic output should be seamlessly integrated into the user’s
task. [16] [8].

The system should avoid discord between the user’s task and the haptic display. [16]
[8].
The system should provide consistent, accurate haptic interaction.[16] [8].


















The system should provide intuitive haptic interaction. [16] [8].
The system should provide intuitive haptic interaction. [16] [8].
precise joint rotations
The system should avoid requiring minute, precise joint rotations, particularly at
distal segments. [9] [8].
. The system should avoid causing user fatigue. [16] [8].
b. The system should avoid requiring static positions at or near the end range of
motion to minimize kinesthetic interaction fatigue.
[9] [8].
c. The system should ensure user comfort over extended periods of time. [7]
The system should use very high spatial resolutions to increase haptic device ease of
use. [16] [8].
The system should encode haptic information using combinations of strength, speed,
high-resolution force, and position that are effectively presented. [16]
The system should effectively use haptic feedback in areas where other senses are
unusable. [16] [8].
NOTE: Haptics is rarely used for spatial discrimination by itself (except in dark
environments). [13] [8].
While the guidelines in all other subsections (other than 3.1.2) relate to both the unimodal and the multi-modal use of tactile / haptic interactions, there is additional
guidance that applies specifically to multi-modal use [8].
According to Popescu et. al., "multisensory feedback is not just the sum of visual,
auditory and somatic feedback, since there is redundancy and transposition in the
human sensorial process.” [13] [8].
The system should use multimedia information when presenting complex haptic
objects [8].
NOTE Users may not understand complex objects when only presented haptic
information. [7] [8].
The system may enhance haptic tasks by using other senses and vibratory cues. [16]
[8].
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

The system may make use of tactile stimuli to convey additional information, beyond
that presented via other modalities. [9] [8].
EXAMPLE A user performing a visual spatial attention task uses tactile information
to communicate warnings. [9] [8].However, care must be taken to use the device for
the intended purpose. Inappropriate use may damage the device or can cause injuries.
7. Impacts
7.1. Societal Concern
We believe that the tactile display will have a positive impact on the society by providing more
accommodation and better way of communication to the visually impaired group of the society. The
business community will also be benefited as the display provides efficient way to communicate with the
visually impaired. By providing more accommodation to the visually impaired, the challenge that this
group of the society face can be reduced and their life quality can be improved.
7.2. Ethical Concern
We could not be able to anticipate how and when the tactile display can be used in a manner that
is against human moral codes, norms and values. However, care must be taken to use the device
for the intended purpose only. Inappropriate use may damage the device or can cause injuries.
7.3. Environmental Concern
All the material involved or used in this projects are not toxic and does not have any negative
impact on the environment and the devise intended users. The thermoplastics used (PLA) in this
project is safe and biodegradable.
7.4. Safety Concern
The tactile display can be little bit heavier, so appropriate measures should be taken during
transport or use of the device. Just like any other electrical device, precautions must be followed
for proper and intended use.
8. Team
Project adviser: Prof Ping Chen
Team Members : Binyam Gemeda
Kalung Ma
8.1. Team Member Responsibilities
Binyam Gemeda: 3D designing of Tactile Display, 3D printing
Kalung Ma : Stepper Motor Selections, Interfacing with 3D printed parts
Team Members (both): Stepper motor controlling and testing, Atmel Studio 6 coding, Device
implementation and testing, Find solution for the application software
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8.2. Team Organization
The team was formed in October 22 of 2015 and began having weekly group meeting. Group
meeting is held on every single Monday and Wednesday at 1 pm in Library. 8 floor of Healey
Library is a perfect place for group discussion. Students are allowed to stay together and discuss.
The weekly meeting and Monthly timeline are shown in Table 1, Table 2 and Figure 20.
Table 1 – Weekly Schedule of Meeting
Date
Description
10/26/2015
Discuss the idea of Tactile Display
10/28/2015
Discuss the criteria, difficulties and functionalities of the project design and
set up a group meeting schedule
11/2/2015
Discuss work distribution, do research and start doing pre-proposal
11/4/2015
Discuss the managing time, budget and resources
11/9/2015
Discuss the impacts of societal, ethical, risk, and safety
11/11/2015
Review the comments from Prof. Cuckov and revise the pre-proposal
11/16/2015
Review the pre-proposal
11/18/2015
Discuss and review the pre-proposal from customer interactions and work
on final team project proposal
11/23/2015
Discuss regulations such as copyright, liability and standards
11/25/2015
Review the comments from Advisor and revise the final proposal
11/30/2015
Review the comments from Advisor and revise the final proposal
12/2/2015
Finish up the preliminary design and final proposal
12/7/2015
Discuss the final report and prepare the final project presentation
12/9/2015
Discuss the final report and prepare the final project presentation
September
October
November
December
Table 2 – Monthly Timeline
Focus on project ideas and project bids
Focus on project synopses
Focus on the feasibility study, pre-proposal,
review comments from Prof. Cuckov, Advisor
and Customers.
Proposal due: November 15th, 2015
Discuss the final proposal and presentation
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January
February
March
April
May
Start the construction part and work
subsystems
Focus on construction part and review the
problems and difficulties
Programming of application software
Programming of application software Focus
on combining all parts of the project design
and solve the problem if the design
does not work
Focus on final report and presentation
Fig 20.Chronology of Gantt chart.
8.3. Milestones
1.
Complete 3D Design and Print
Complete the 3d designing and printing would be the first milestones for this project.
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2.
Interfacing and Single Filament Block Testing
Motor and 3D part interfacing and testing would be conducted at this stage. By using simple
stepper motor coding the functionality of single filament unites will be tested.
3.
Atmel Studio 6 coding and Devise Implementation
Stepper motor control and programming will be performed at this stage. Once the code
developed and tested for its functionality, devise implementation will be performed.
4.
Touch sensor and Sound record/playback module integration
The filaments will be mounted with touch sensor and pre-recorded sound will be play
back. The sound will identify what is touch or the location or any information
associated with the location of the filament.
5.
Exploration for Application Software
Application software is needed to transfer information from a PC to the Tactile Display. All
possible options will be considered at this stage.
8.4. Budget
Parts
Atmega32
Atmega16/MUX/DMUX
PLA/ABS
MOTORS
H-bridge/driver
ISD 1932
Button
Total
Quantity
2
16/4
2kg
150
10
1
100
$ 789.14
Price
3.98/each
4.98/each
30/kg
4.00/each
4.35/12.45 each
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0.32/ each
The cost for power supply and management is under review. Once that is completed, it will be
included in the total cost analysis.
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Bibliography
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technologies with applications in biomedical engineering."Sensors and Actuators A: physical
179 (2012): 17-31.
[2] Jones, Lynette A., and Nadine B. Sarter. "Tactile displays: Guidance for their design and
application." Human Factors: The Journal of the Human Factors and Ergonomics Society 50.1
(2008): 90-111.
[3] McGrath, B., et al. "–TACTILE ACTUATOR TECHNOLOGY." Tactile Displays for
orientation, navigation and communication in air, sea and land environments (2008): 4.
[4] Lee, Mark H., and Howard R. Nicholls. "Review Article Tactile sensing for mechatronics—a
state of the art survey." Mechatronics 9.1 (1999): 1-31.
[5] Rotard, Martin, Christiane Taras, and Thomas Ertl. "Tactile web browsing for blind people."
Multimedia Tools and Applications 37.1 (2008): 53-69.
[6] Benali-Khoudja, Mohamed, et al. "Tactile interfaces: a state-of-the-art survey." Int.
Symposium on Robotics. Vol. 31. 2004.
[7] Van Erp, Jan BF, Jim Carter, and Ian Andrew. "Iso’s work on tactile and haptic interaction
guidelines." Proceedings of Eurohaptics. 2006.
[8] Carter, Jim, and David Fourney. "Research based tactile and haptic interaction guidelines."
Guidelines on Tactile and Haptic Interaction (GOTHI 2005) (2005): 84-92.
[9] Van Erp, Jan BF, et al. "Setting the standards for haptic and tactile interactions: ISO’s work."
Haptics: Generating and Perceiving Tangible Sensations. Springer Berlin Heidelberg, 2010. 353358.
[10] Bau, O., Poupyrev,I.,Israr,A.,and Harrison,C. TeslaTouch: Electrovibration for Touch
Surfaces. Proceedings of the 23rd Annual ACM Symposium on User Interface Software and
Technology.
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