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Award Detail

Doing Business As Name:Iowa State University
  • Christian Schwartz
  • (515) 294-1431
Award Date:11/02/2012
Estimated Total Award Amount: $ 147,864
Funds Obligated to Date: $ 147,864
  • FY 2010=$147,864
Start Date:08/15/2012
End Date:12/31/2014
Transaction Type:Grant
Awarding Agency Code:4900
Funding Agency Code:4900
CFDA Number:47.041
Primary Program Source:040100 NSF RESEARCH & RELATED ACTIVIT
Award Title or Description:Empowering the visually impaired by understanding links between tactility and properties of surfaces
Federal Award ID Number:1304404
DUNS ID:005309844
Parent DUNS ID:005309844
Program:Disability & Rehab Engineering
Program Officer:
  • Alex Leonessa
  • (703) 292-0000

Awardee Location

Street:1138 Pearson
Awardee Cong. District:04

Primary Place of Performance

Organization Name:Iowa State University
Cong. District:04

Abstract at Time of Award

In blind or visually impaired (BVI) individuals, a primary means of delivering information is through tactile channels such as Braille and raised-line illustrations. However, these systems present complications in translating non-tactile information to these forms, and also result in cumbersome and space-consuming materials for instruction and communication of technical and artistic ideas. This is a considerable hindrance to the ability of BVI persons to fully participate in engineering and the sciences, which rely heavily on the presentation and manipulation of graphical information during instruction and peer discussion. A revolutionary improvement in technology is required to address this issue. Currently, there is a lack of fundamental science to address how surfaces can be manipulated to convey tactile information. Thus, there is a critical need to better understand the causative relationships between surface properties (mechanical, textural, thermal, chemical) and the resulting tactile attributes of surfaces (texture, softness, abrasiveness, etc.), as well as a need to train engineers to objectively consider tactility and other sensory attributes during design. Addressing these needs will have a transformative effect not only on the materials science-based understanding of human interaction with surfaces, but also on the paradigms of education and professional occupation of the visually impaired. The objectives of this proposed work are to test the hypotheses that: 1. Surface tactility can be described quantitatively by a collection of objective tactile descriptors and associated scores, 2. Objective causal relationships exist that relate tactile attributes to engineering-based surface properties, 3. Tactility can be used with a problem-based learning approach to educate engineers to address sensory design goals, as well as attract BVI students to study engineering and science in college. This work will employ a thorough experimental approach. Quantitative Descriptive Analysis (QDA) will be used with human evaluators to meticulously identify and quantify the individual tactile descriptors of both textile and solid polymer surfaces. Surfaces will also be analyzed by a number of methods including tribological testing, dynamic mechanical analysis, and surface topography measurement. Statistical and neural network techniques will be employed to identify and investigate relationships between the tactile descriptors and the surface property values. The research tasks will be closely integrated with the educational activities of this work through a number of innovative mechanisms. Intellectual Merit. This work is novel and transformative because it will be the first broad engineering based approach to understanding how to directly control and optimize the tactile feel of a variety of surfaces and thus produce insights into efficient means of conveying tactile information. This knowledge will also foster new fields of research that will bridge the gap between engineering and neuroscience. Control of tactility will revolutionize paradigms in such fields as haptic displays and textiles, but more importantly will open new doors into the possibilities for educational tools for BVI students as well as technologies to facilitate greater participation of these persons in engineering and science. There is a unique synergy with the biotribology and polymers background of the PI and the resources of his institution that maximize the probability of successful completion of this work. Broader Impacts. These results will have far-reaching impact on the fundamental understanding of the materials science based origins of tactility. The work will also serve as an instructional platform to expose students to design experiences that incorporate sensory assessment of engineered products. A problem based pedagogical approach, termed iSENSE, will be incorporated into graduate and capstone design courses. A goal of iSENSE is to enable engineering students to transcend discipline paradigms in order to address real-world design challenges that involve sensory assessment. iSENSE also targets the recruitment of middle- and high school BVI students to engineering and science, by their participation in PI-led enrichment courses that will incorporate tactility into engineering design inspired activities. Undergraduate engineering students will work on design projects to develop instructional technology to help facilitate the learning of the BVI students during these enrichment courses.

Publications Produced as a Result of this Research

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Darden, M.A. and Schwartz, C.J. "Investigation of friction mechanisms during the sliding of elastomers against hard parallel-ridge textures" Tribology International, v.63, 2013, p.2. doi: 

Darden, M and Schwartz, C.J. "Skin tribology phenomena associated with reading braille print: the influence of cell patterns and skin behavior on coefficient of friction" Wear, v., 2015, p.. doi:doi:10.1016/j.wear.2014.12.053 

Project Outcomes Report


This Project Outcomes Report for the General Public is displayed verbatim as submitted by the Principal Investigator (PI) for this award. Any opinions, findings, and conclusions or recommendations expressed in this Report are those of the PI and do not necessarily reflect the views of the National Science Foundation; NSF has not approved or endorsed its content.

When someone picks up, touches or otherwise comes in contact with a product, there is an immediate sensation of how the product feels against the skin. We analyze, often subconsciously, not only the identity and quality of the product based on feel, but we also often pick up cues about how to use the product based on feel. If you are sighted, imagine learning almost everything through your sense of touch and now think about how cumbersome it might be if your first encounters with algebra, geometry, physics and chemistry were based solely on touch instead of sight. This is how blind and visually impaired (BVI) students are introduced to STEM fields, and why it is important to better understand the fundamental phenomena that occur during the touch interaction. This investigation sought to find connections between the attributes of touch and the engineering and material properties of surfaces, in order to propose ways to better include BVI students not only in STEM understanding but also in the engineering and science professions. As a result, we have conducted the first in-depth study of the frictional interaction of fingertip-on-braille contact and from this have learned about potential ways to improve the usefulness of tactile communication as a tool for STEM education.

This project included a number of activities to answer the research questions. The work focused on understanding the fundamental physics of the frictional interaction between a fingertip and a braille-printed surface. The science of friction is called tribology, and this study paved new roads into the understanding of skin tribology for the purposes of tactile communication. By extensive experimental investigation, we learned that finger-on-braille friction is governed by two classical mechanisms that have been known for decades to be involved in industrial friction issues. This was the first validation that they also play a role in braille reading. The first aspect of skin tribology that we discovered to be important was adhesive friction, which is the resistance to sliding caused by the numerous infinitesimal adhesive bonds produced between skin and surface during contact. The force required to continually break these bonds contributes to overall friction. The second component of friction was due to hysteresis of the soft fingertip as it slid over each dot feature. Viscoelastic materials, like skin, do not instantaneously ‘spring back’ on the trailing side of a dot as the soft skin encounters and slides over the dot. At any instant during sliding, there is less skin contact on the trailing side of the dot versus the leading side, and thus an imbalance in lateral force is realized. This, too, creates a resistance to sliding in addition to adhesion. One of the key findings of this work was to identify these two friction mechanisms and to discover that hysteresis dominates finger-on-braille sliding to the extent that friction due to braille media (paper, metal, plastic) is secondary and not as important as the dots themselves. Another key finding of this work is that when braille dots get close together, they can behave like a single dot in terms of friction. It is hypothesized that this behavior may be the cause of difficulty for people learning to read braille, because they have not yet learned to use non-friction cues to indicate the presence of multiple dots while reading.

A final outcome of this work was to forge a tight collaboration with the Texas School for the Blind and Visually Impaired and the Iowa Braille School, in developing engineering content for actively engaging middle and high-school BVI students in meaningful STEM activities. This partnership allows us to offer enrichment courses such as ProblemBusters! to these students, so that they can explore their imagination while strengthening their engineering, science and reasoning skills to acc...

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