This document provides instructions for building a multi-touch display using FTIR technology. It discusses modifying a webcam to detect infrared light, treating acrylic by sawing, sanding and polishing it, building a frame, wiring an LED circuit, and using projection. The guide is intended for readers aged 12 to 70 and assumes the reader has basic handy skills. It aims to explain the process simply and help people understand and build their own multi-touch displays.
This document summarizes Session 4 of a Web Accessibility Workshop. It covers WAI ARIA, including an introduction to ARIA and how it addresses accessibility issues with dynamic content. The core ARIA components are then discussed, including abstract roles, widget roles, document structure roles, and document landmark roles. Examples are provided throughout to illustrate how ARIA adds semantics and information to make interfaces understandable to assistive technologies.
Designing better user interfaces sets out to teach interface design by talking through concrete examples: what works, what doesn’t work. A good interface consists of a thousand details done right. This presentation is all about those details.
The Next Generation of Flash User ExperienceKevin Suttle
Kevin Suttle is a Flash Platform UX Architect who has been working with Flash for over 5 years. In his presentation, he discusses the current "battle for platform supremacy" between Flash and HTML5. However, he argues that users just want great content and experiences, and both Flash and HTML5 are capable of providing that. He outlines many new user experience focused APIs in Flash Player 10.1 for touch, gestures, accessibility and more. He advocates for an approach of "mobilizing, not minimizing" applications to provide adaptive experiences across devices using Flash technologies like AIR.
This document provides tips for creating effective presentations with minimal text and engaging visuals. It recommends including no more than 6 words per slide to reduce cognitive load on the audience. Images should illustrate key points rather than just decorate slides. Simple, clean designs without animations or distractions are best. It also discusses choosing presentation tools like PowerPoint, options for embedding video, using readable fonts, and finding free images and video content within copyright restrictions.
HTML5 Meetup | Back to Basics: Wireframing & PlanningPaul Crimi
This is the keynote presentation from the HTML5 Meetup in Toronto, CA that took place on February 27, 2014.
Planning your projects at the very beginning can be a fun yet daunting task. Showing clients early concepts, prototypes, wireframes and ideas at early stages can help you land the contract, or perhaps see concerns or new features for your own project that wasn’t apparent before. Michael McArthur and Paul Crimi, both of whom are Product Designers at BNOTIONS, are going to walk us through their processes of how they begin a project, what resources they use, and what goes on in their minds as they get everything off the ground.
Minnesota Library Association Presentation 2010nickprieve
Here is a preview of what I will be presenting at MLA this year. It is a valuble resource to libraries trying to find new technologies to solve problems.
The document summarizes a presentation about Papervision3D, an open source 3D engine for Flash. It discusses downloading and setting up Papervision3D, designing interfaces for 3D applications, and provides examples of both good and bad 3D Flash applications. The presentation covers topics such as the basics of Papervision3D, getting started with 3D development in Flash, and designing effective user experiences for 3D Flash games and sites.
This document summarizes Session 4 of a Web Accessibility Workshop. It covers WAI ARIA, including an introduction to ARIA and how it addresses accessibility issues with dynamic content. The core ARIA components are then discussed, including abstract roles, widget roles, document structure roles, and document landmark roles. Examples are provided throughout to illustrate how ARIA adds semantics and information to make interfaces understandable to assistive technologies.
Designing better user interfaces sets out to teach interface design by talking through concrete examples: what works, what doesn’t work. A good interface consists of a thousand details done right. This presentation is all about those details.
The Next Generation of Flash User ExperienceKevin Suttle
Kevin Suttle is a Flash Platform UX Architect who has been working with Flash for over 5 years. In his presentation, he discusses the current "battle for platform supremacy" between Flash and HTML5. However, he argues that users just want great content and experiences, and both Flash and HTML5 are capable of providing that. He outlines many new user experience focused APIs in Flash Player 10.1 for touch, gestures, accessibility and more. He advocates for an approach of "mobilizing, not minimizing" applications to provide adaptive experiences across devices using Flash technologies like AIR.
This document provides tips for creating effective presentations with minimal text and engaging visuals. It recommends including no more than 6 words per slide to reduce cognitive load on the audience. Images should illustrate key points rather than just decorate slides. Simple, clean designs without animations or distractions are best. It also discusses choosing presentation tools like PowerPoint, options for embedding video, using readable fonts, and finding free images and video content within copyright restrictions.
HTML5 Meetup | Back to Basics: Wireframing & PlanningPaul Crimi
This is the keynote presentation from the HTML5 Meetup in Toronto, CA that took place on February 27, 2014.
Planning your projects at the very beginning can be a fun yet daunting task. Showing clients early concepts, prototypes, wireframes and ideas at early stages can help you land the contract, or perhaps see concerns or new features for your own project that wasn’t apparent before. Michael McArthur and Paul Crimi, both of whom are Product Designers at BNOTIONS, are going to walk us through their processes of how they begin a project, what resources they use, and what goes on in their minds as they get everything off the ground.
Minnesota Library Association Presentation 2010nickprieve
Here is a preview of what I will be presenting at MLA this year. It is a valuble resource to libraries trying to find new technologies to solve problems.
The document summarizes a presentation about Papervision3D, an open source 3D engine for Flash. It discusses downloading and setting up Papervision3D, designing interfaces for 3D applications, and provides examples of both good and bad 3D Flash applications. The presentation covers topics such as the basics of Papervision3D, getting started with 3D development in Flash, and designing effective user experiences for 3D Flash games and sites.
empowerment-4_compress.pdf in senior high school students PSUaliyahdalogdogan
This document provides an overview of online platforms and applications for developing ICT content. It discusses the nature and purposes of various online platforms, including presentation, cloud computing, social media, web page creation, and file management platforms. Basic principles of web design are also covered, such as using visual language, balance, focus on content and simplification. Common web design elements like illustrations, links, buttons and images are explained. The document concludes by giving instructions on getting started with specific platforms like SlideShare, Google Drive and Tumblr.
This document provides information on and links to various digital tools that can be used for educational purposes. It describes tools for creating videos, such as Animoto, Adobe Spark Video, and AnimateMaker. It also mentions tools for audio editing (Audacity), blogging (Blogger), video editing (Biugo), mind mapping (Bubbl.us), digital book creation (Book Creator), graphic design and video creation (Canva), learning to code (Code.org), photo editing and captioning (ChatterPix), language learning resources (LanguageForWork), concept mapping (CmapsTools), organizing research papers (CiteULike), language learning (Duolingo), screen recording (DURecorder),
Norville Barnes gets a chance to shine when he is promoted to CEO of his company despite only being able to poorly pitch his idea for a children's toy. His invention, the hula hoop, becomes wildly popular not through marketing but by other children seeing one child enjoying it. The speaker argues that new web technologies are like the hula hoop - they don't need marketing and will succeed if developers embrace them to build fun and engaging experiences that others will want to use. Developers should use HTML5, CSS, JavaScript and other open technologies to make the web better for all.
The document discusses the features and capabilities of the INPLEX collaboration software. It describes how INPLEX acts as a central lobby or homepage that allows users to check on meeting status, tutorials, and advertisements. Key features highlighted include co-browsing websites, co-gesturing, co-drawing, co-chatting, file sharing, and video synchronization across any number of participants from different locations. A variety of use cases are provided such as remote training, design collaboration, telemedicine, and more.
This document provides a series of questions to consider when auditing the user experience and user interface of a digital product. It covers topics like understanding the value proposition, assessing the onboarding process, evaluating the information architecture and flow, analyzing how personalized and integrated the experience is, and ensuring the interface follows best practices. The questions are meant to be considered in chronological order and cover areas like discovery, understanding, engagement, retention, and business viability.
While42 is a French tech community for engineers and those with computer science degrees from French institutions. All members must be French speakers with technical backgrounds. The goal is for each local chapter to know each other personally, staying relatively small. Real connections between real people are emphasized over large size or scope.
Unit – II: NEW HORIZONS IN ICT
Recent trends in the area of ICT - Interactive Video-Interactive White Board- videoconferencing –M-learning, Social Media- Community Radio: Gyan Darshan, Gyanvani, Sakshat Portal, e-Gyankosh, Blog, MOOC, Whatsapp, Facebook, Twitter etc.-Recent experiments in the third world countries and pointers for India with reference to Education.
Creating a Universal Design System for Web, Mobile, Wearables, and XRdamirkotoric
Creating a Universal Design System for Web, Mobile, Wearables, and XR
1. The authors created a design system to provide a cohesive experience across mobile, tablet, desktop, AR and VR platforms for their archaeological apps.
2. They drew from existing design systems like Material Design and customized components, colors, and typography to match their brand while ensuring consistency.
3. Their design system is implemented 30% from Material Design foundations and 70% from their own custom components to provide the needed features for their products across different devices and platforms.
Macromedia Director is a multimedia authoring software that allows users to create applications modeled after a movie, with the user as the director. It supports
This document provides an overview of free and open source software that can be used for online learning. It discusses tools for schools, instructors, and students including learning management systems like Moodle and Sakai. It also lists specific applications for tasks like content management, audio/video, development, and productivity. The document aims to showcase cost-effective alternatives to proprietary software for education.
This document outlines the process of industrializing an open source software and selling it as a product. It discusses securing the intellectual property of the code, improving development practices through version control, continuous integration, testing and documentation. It also covers challenges of determining customer needs when no existing market exists, balancing innovation and technical capabilities with market demands, and the importance of user satisfaction over technical features alone. The conclusion reflects on how research labs can foster innovation and how 13 jobs have been created by building a company around code originally developed through academic research.
OpenY: Scaling and Sharing with Custom Drupal DistributionDrupalCamp Kyiv
The promise of open source technology has always been about the ability to spread and scale. This is exemplified with Drupal distributions. In this session we will examine how we are leveraging open source, Drupal 8 with one of the largest federated non-profit organization in the world, the YMCA. We will focus specifically on a community driven initiative, OpenY, which is a Drupal distribution custom built for YMCAs everywhere. Some specific topics we will go over include:
Leveraging open source software to foster sharing and collaboration.
Developing a communication strategy focused on key benefits of Drupal and open source, such as cost and speed of innovation.
Story about building custom Drupal 8 Distribution
The beginning of OpenY distribution.
The biggest technical challenges:
How to provide scalable and flexible architecture?
How to create integrations with 3rd party services?
How to provide smooth and easy Installation process?
How to support friendly Upgrade Path for the customers?
How to setup sustainable Continuous Integration for the Drupal 8 Distribution?
The road to the 1st major release 1.0
Where is OpenY community now and what are our plans.
This session will reveal how open source software and Drupal can drive business results with better customer experiences, faster speed to market, and lower costs. It should be beneficial for all community members regardless of the position.
Working on an open-source project captures the imagination. It taps straight into an emotional desire to make the world a better place. What an amazing, brave and inspiring idea! What a huge pool of energy and enthusiasm!?? All that energy and within moments a casual idea can turn into committed code and a feature - KAPPOW!
Dream or nightmare? How do we make sure that energetic, enthusiastic, intelligent, talented people direct their energy into applications, features and functions that people want to use?Who is this mythical end-user who bends to our will and is eager to invite all our fantastic features into their life? Are they a bug squished into the punch-card of our ideal development process or a valuable tool that will help us make applications that are loved by millions? We have to start thinking about target users. Who are they? What do they care about? How do we find out and how do we keep that central to our design and development processes? From Paper Cuts to UX Advocates what are they and why should you care about them.
*Please note that these slides were for a presentation so may make little sense without me be highly amusing and informative at the same time as you are looking at them.
Technologies, Places, Business Models for Open Design @ Pixelversity, Helsink...Massimo Menichinelli
The document discusses technologies, places, and business models for open design. It begins by describing various digital fabrication technologies like 3D printing, laser cutting, and CNC milling. It then discusses makerspaces, hacker spaces, and fab labs as places where open design projects can be made. Finally, it explores potential business models for open design like crowdfunding, selling services, and dual licensing of open and proprietary designs and software. The overall focus is on how designers can engage with both open technologies and business opportunities.
Hybrid solutions for exhibitions stand designSerena Ferrari
FROM EXHIBITION STAND DESIGN TO EXPERIENCE DESIGN.
COVID-19 has accelerated the integration of virtual and in-person event and exhibition delivery, requiring a fundamental change in how we engage with customers to maintain relevance.
Furthermore, a recent GES USA survey has revealed that to most people hybrid is another way to attend virtually or in-person and not a differentiated format.
The main challenge for exhibition stand designers and event planners is how to make the hybrid experience meaningful, and the technology easy to use.
These slides are from a 2 hour presentation called Design for Developers.
The goal of Design for Developers is to teach interface design as a set of rules: there are some good default values for a lot of design decisions that you should remember, there is a “scientific” way of approaching things like alignment, even though many designers will tell you it’s something you should “feel”.
Use PyCharm for remote debugging of WSL on a Windo cf5c162d672e4e58b4dde5d797...shadow0702a
This document serves as a comprehensive step-by-step guide on how to effectively use PyCharm for remote debugging of the Windows Subsystem for Linux (WSL) on a local Windows machine. It meticulously outlines several critical steps in the process, starting with the crucial task of enabling permissions, followed by the installation and configuration of WSL.
The guide then proceeds to explain how to set up the SSH service within the WSL environment, an integral part of the process. Alongside this, it also provides detailed instructions on how to modify the inbound rules of the Windows firewall to facilitate the process, ensuring that there are no connectivity issues that could potentially hinder the debugging process.
The document further emphasizes on the importance of checking the connection between the Windows and WSL environments, providing instructions on how to ensure that the connection is optimal and ready for remote debugging.
It also offers an in-depth guide on how to configure the WSL interpreter and files within the PyCharm environment. This is essential for ensuring that the debugging process is set up correctly and that the program can be run effectively within the WSL terminal.
Additionally, the document provides guidance on how to set up breakpoints for debugging, a fundamental aspect of the debugging process which allows the developer to stop the execution of their code at certain points and inspect their program at those stages.
Finally, the document concludes by providing a link to a reference blog. This blog offers additional information and guidance on configuring the remote Python interpreter in PyCharm, providing the reader with a well-rounded understanding of the process.
Rainfall intensity duration frequency curve statistical analysis and modeling...bijceesjournal
Using data from 41 years in Patna’ India’ the study’s goal is to analyze the trends of how often it rains on a weekly, seasonal, and annual basis (1981−2020). First, utilizing the intensity-duration-frequency (IDF) curve and the relationship by statistically analyzing rainfall’ the historical rainfall data set for Patna’ India’ during a 41 year period (1981−2020), was evaluated for its quality. Changes in the hydrologic cycle as a result of increased greenhouse gas emissions are expected to induce variations in the intensity, length, and frequency of precipitation events. One strategy to lessen vulnerability is to quantify probable changes and adapt to them. Techniques such as log-normal, normal, and Gumbel are used (EV-I). Distributions were created with durations of 1, 2, 3, 6, and 24 h and return times of 2, 5, 10, 25, and 100 years. There were also mathematical correlations discovered between rainfall and recurrence interval.
Findings: Based on findings, the Gumbel approach produced the highest intensity values, whereas the other approaches produced values that were close to each other. The data indicates that 461.9 mm of rain fell during the monsoon season’s 301st week. However, it was found that the 29th week had the greatest average rainfall, 92.6 mm. With 952.6 mm on average, the monsoon season saw the highest rainfall. Calculations revealed that the yearly rainfall averaged 1171.1 mm. Using Weibull’s method, the study was subsequently expanded to examine rainfall distribution at different recurrence intervals of 2, 5, 10, and 25 years. Rainfall and recurrence interval mathematical correlations were also developed. Further regression analysis revealed that short wave irrigation, wind direction, wind speed, pressure, relative humidity, and temperature all had a substantial influence on rainfall.
Originality and value: The results of the rainfall IDF curves can provide useful information to policymakers in making appropriate decisions in managing and minimizing floods in the study area.
empowerment-4_compress.pdf in senior high school students PSUaliyahdalogdogan
This document provides an overview of online platforms and applications for developing ICT content. It discusses the nature and purposes of various online platforms, including presentation, cloud computing, social media, web page creation, and file management platforms. Basic principles of web design are also covered, such as using visual language, balance, focus on content and simplification. Common web design elements like illustrations, links, buttons and images are explained. The document concludes by giving instructions on getting started with specific platforms like SlideShare, Google Drive and Tumblr.
This document provides information on and links to various digital tools that can be used for educational purposes. It describes tools for creating videos, such as Animoto, Adobe Spark Video, and AnimateMaker. It also mentions tools for audio editing (Audacity), blogging (Blogger), video editing (Biugo), mind mapping (Bubbl.us), digital book creation (Book Creator), graphic design and video creation (Canva), learning to code (Code.org), photo editing and captioning (ChatterPix), language learning resources (LanguageForWork), concept mapping (CmapsTools), organizing research papers (CiteULike), language learning (Duolingo), screen recording (DURecorder),
Norville Barnes gets a chance to shine when he is promoted to CEO of his company despite only being able to poorly pitch his idea for a children's toy. His invention, the hula hoop, becomes wildly popular not through marketing but by other children seeing one child enjoying it. The speaker argues that new web technologies are like the hula hoop - they don't need marketing and will succeed if developers embrace them to build fun and engaging experiences that others will want to use. Developers should use HTML5, CSS, JavaScript and other open technologies to make the web better for all.
The document discusses the features and capabilities of the INPLEX collaboration software. It describes how INPLEX acts as a central lobby or homepage that allows users to check on meeting status, tutorials, and advertisements. Key features highlighted include co-browsing websites, co-gesturing, co-drawing, co-chatting, file sharing, and video synchronization across any number of participants from different locations. A variety of use cases are provided such as remote training, design collaboration, telemedicine, and more.
This document provides a series of questions to consider when auditing the user experience and user interface of a digital product. It covers topics like understanding the value proposition, assessing the onboarding process, evaluating the information architecture and flow, analyzing how personalized and integrated the experience is, and ensuring the interface follows best practices. The questions are meant to be considered in chronological order and cover areas like discovery, understanding, engagement, retention, and business viability.
While42 is a French tech community for engineers and those with computer science degrees from French institutions. All members must be French speakers with technical backgrounds. The goal is for each local chapter to know each other personally, staying relatively small. Real connections between real people are emphasized over large size or scope.
Unit – II: NEW HORIZONS IN ICT
Recent trends in the area of ICT - Interactive Video-Interactive White Board- videoconferencing –M-learning, Social Media- Community Radio: Gyan Darshan, Gyanvani, Sakshat Portal, e-Gyankosh, Blog, MOOC, Whatsapp, Facebook, Twitter etc.-Recent experiments in the third world countries and pointers for India with reference to Education.
Creating a Universal Design System for Web, Mobile, Wearables, and XRdamirkotoric
Creating a Universal Design System for Web, Mobile, Wearables, and XR
1. The authors created a design system to provide a cohesive experience across mobile, tablet, desktop, AR and VR platforms for their archaeological apps.
2. They drew from existing design systems like Material Design and customized components, colors, and typography to match their brand while ensuring consistency.
3. Their design system is implemented 30% from Material Design foundations and 70% from their own custom components to provide the needed features for their products across different devices and platforms.
Macromedia Director is a multimedia authoring software that allows users to create applications modeled after a movie, with the user as the director. It supports
This document provides an overview of free and open source software that can be used for online learning. It discusses tools for schools, instructors, and students including learning management systems like Moodle and Sakai. It also lists specific applications for tasks like content management, audio/video, development, and productivity. The document aims to showcase cost-effective alternatives to proprietary software for education.
This document outlines the process of industrializing an open source software and selling it as a product. It discusses securing the intellectual property of the code, improving development practices through version control, continuous integration, testing and documentation. It also covers challenges of determining customer needs when no existing market exists, balancing innovation and technical capabilities with market demands, and the importance of user satisfaction over technical features alone. The conclusion reflects on how research labs can foster innovation and how 13 jobs have been created by building a company around code originally developed through academic research.
OpenY: Scaling and Sharing with Custom Drupal DistributionDrupalCamp Kyiv
The promise of open source technology has always been about the ability to spread and scale. This is exemplified with Drupal distributions. In this session we will examine how we are leveraging open source, Drupal 8 with one of the largest federated non-profit organization in the world, the YMCA. We will focus specifically on a community driven initiative, OpenY, which is a Drupal distribution custom built for YMCAs everywhere. Some specific topics we will go over include:
Leveraging open source software to foster sharing and collaboration.
Developing a communication strategy focused on key benefits of Drupal and open source, such as cost and speed of innovation.
Story about building custom Drupal 8 Distribution
The beginning of OpenY distribution.
The biggest technical challenges:
How to provide scalable and flexible architecture?
How to create integrations with 3rd party services?
How to provide smooth and easy Installation process?
How to support friendly Upgrade Path for the customers?
How to setup sustainable Continuous Integration for the Drupal 8 Distribution?
The road to the 1st major release 1.0
Where is OpenY community now and what are our plans.
This session will reveal how open source software and Drupal can drive business results with better customer experiences, faster speed to market, and lower costs. It should be beneficial for all community members regardless of the position.
Working on an open-source project captures the imagination. It taps straight into an emotional desire to make the world a better place. What an amazing, brave and inspiring idea! What a huge pool of energy and enthusiasm!?? All that energy and within moments a casual idea can turn into committed code and a feature - KAPPOW!
Dream or nightmare? How do we make sure that energetic, enthusiastic, intelligent, talented people direct their energy into applications, features and functions that people want to use?Who is this mythical end-user who bends to our will and is eager to invite all our fantastic features into their life? Are they a bug squished into the punch-card of our ideal development process or a valuable tool that will help us make applications that are loved by millions? We have to start thinking about target users. Who are they? What do they care about? How do we find out and how do we keep that central to our design and development processes? From Paper Cuts to UX Advocates what are they and why should you care about them.
*Please note that these slides were for a presentation so may make little sense without me be highly amusing and informative at the same time as you are looking at them.
Technologies, Places, Business Models for Open Design @ Pixelversity, Helsink...Massimo Menichinelli
The document discusses technologies, places, and business models for open design. It begins by describing various digital fabrication technologies like 3D printing, laser cutting, and CNC milling. It then discusses makerspaces, hacker spaces, and fab labs as places where open design projects can be made. Finally, it explores potential business models for open design like crowdfunding, selling services, and dual licensing of open and proprietary designs and software. The overall focus is on how designers can engage with both open technologies and business opportunities.
Hybrid solutions for exhibitions stand designSerena Ferrari
FROM EXHIBITION STAND DESIGN TO EXPERIENCE DESIGN.
COVID-19 has accelerated the integration of virtual and in-person event and exhibition delivery, requiring a fundamental change in how we engage with customers to maintain relevance.
Furthermore, a recent GES USA survey has revealed that to most people hybrid is another way to attend virtually or in-person and not a differentiated format.
The main challenge for exhibition stand designers and event planners is how to make the hybrid experience meaningful, and the technology easy to use.
These slides are from a 2 hour presentation called Design for Developers.
The goal of Design for Developers is to teach interface design as a set of rules: there are some good default values for a lot of design decisions that you should remember, there is a “scientific” way of approaching things like alignment, even though many designers will tell you it’s something you should “feel”.
Use PyCharm for remote debugging of WSL on a Windo cf5c162d672e4e58b4dde5d797...shadow0702a
This document serves as a comprehensive step-by-step guide on how to effectively use PyCharm for remote debugging of the Windows Subsystem for Linux (WSL) on a local Windows machine. It meticulously outlines several critical steps in the process, starting with the crucial task of enabling permissions, followed by the installation and configuration of WSL.
The guide then proceeds to explain how to set up the SSH service within the WSL environment, an integral part of the process. Alongside this, it also provides detailed instructions on how to modify the inbound rules of the Windows firewall to facilitate the process, ensuring that there are no connectivity issues that could potentially hinder the debugging process.
The document further emphasizes on the importance of checking the connection between the Windows and WSL environments, providing instructions on how to ensure that the connection is optimal and ready for remote debugging.
It also offers an in-depth guide on how to configure the WSL interpreter and files within the PyCharm environment. This is essential for ensuring that the debugging process is set up correctly and that the program can be run effectively within the WSL terminal.
Additionally, the document provides guidance on how to set up breakpoints for debugging, a fundamental aspect of the debugging process which allows the developer to stop the execution of their code at certain points and inspect their program at those stages.
Finally, the document concludes by providing a link to a reference blog. This blog offers additional information and guidance on configuring the remote Python interpreter in PyCharm, providing the reader with a well-rounded understanding of the process.
Rainfall intensity duration frequency curve statistical analysis and modeling...bijceesjournal
Using data from 41 years in Patna’ India’ the study’s goal is to analyze the trends of how often it rains on a weekly, seasonal, and annual basis (1981−2020). First, utilizing the intensity-duration-frequency (IDF) curve and the relationship by statistically analyzing rainfall’ the historical rainfall data set for Patna’ India’ during a 41 year period (1981−2020), was evaluated for its quality. Changes in the hydrologic cycle as a result of increased greenhouse gas emissions are expected to induce variations in the intensity, length, and frequency of precipitation events. One strategy to lessen vulnerability is to quantify probable changes and adapt to them. Techniques such as log-normal, normal, and Gumbel are used (EV-I). Distributions were created with durations of 1, 2, 3, 6, and 24 h and return times of 2, 5, 10, 25, and 100 years. There were also mathematical correlations discovered between rainfall and recurrence interval.
Findings: Based on findings, the Gumbel approach produced the highest intensity values, whereas the other approaches produced values that were close to each other. The data indicates that 461.9 mm of rain fell during the monsoon season’s 301st week. However, it was found that the 29th week had the greatest average rainfall, 92.6 mm. With 952.6 mm on average, the monsoon season saw the highest rainfall. Calculations revealed that the yearly rainfall averaged 1171.1 mm. Using Weibull’s method, the study was subsequently expanded to examine rainfall distribution at different recurrence intervals of 2, 5, 10, and 25 years. Rainfall and recurrence interval mathematical correlations were also developed. Further regression analysis revealed that short wave irrigation, wind direction, wind speed, pressure, relative humidity, and temperature all had a substantial influence on rainfall.
Originality and value: The results of the rainfall IDF curves can provide useful information to policymakers in making appropriate decisions in managing and minimizing floods in the study area.
Embedded machine learning-based road conditions and driving behavior monitoringIJECEIAES
Car accident rates have increased in recent years, resulting in losses in human lives, properties, and other financial costs. An embedded machine learning-based system is developed to address this critical issue. The system can monitor road conditions, detect driving patterns, and identify aggressive driving behaviors. The system is based on neural networks trained on a comprehensive dataset of driving events, driving styles, and road conditions. The system effectively detects potential risks and helps mitigate the frequency and impact of accidents. The primary goal is to ensure the safety of drivers and vehicles. Collecting data involved gathering information on three key road events: normal street and normal drive, speed bumps, circular yellow speed bumps, and three aggressive driving actions: sudden start, sudden stop, and sudden entry. The gathered data is processed and analyzed using a machine learning system designed for limited power and memory devices. The developed system resulted in 91.9% accuracy, 93.6% precision, and 92% recall. The achieved inference time on an Arduino Nano 33 BLE Sense with a 32-bit CPU running at 64 MHz is 34 ms and requires 2.6 kB peak RAM and 139.9 kB program flash memory, making it suitable for resource-constrained embedded systems.
Optimizing Gradle Builds - Gradle DPE Tour Berlin 2024Sinan KOZAK
Sinan from the Delivery Hero mobile infrastructure engineering team shares a deep dive into performance acceleration with Gradle build cache optimizations. Sinan shares their journey into solving complex build-cache problems that affect Gradle builds. By understanding the challenges and solutions found in our journey, we aim to demonstrate the possibilities for faster builds. The case study reveals how overlapping outputs and cache misconfigurations led to significant increases in build times, especially as the project scaled up with numerous modules using Paparazzi tests. The journey from diagnosing to defeating cache issues offers invaluable lessons on maintaining cache integrity without sacrificing functionality.
Applications of artificial Intelligence in Mechanical Engineering.pdfAtif Razi
Historically, mechanical engineering has relied heavily on human expertise and empirical methods to solve complex problems. With the introduction of computer-aided design (CAD) and finite element analysis (FEA), the field took its first steps towards digitization. These tools allowed engineers to simulate and analyze mechanical systems with greater accuracy and efficiency. However, the sheer volume of data generated by modern engineering systems and the increasing complexity of these systems have necessitated more advanced analytical tools, paving the way for AI.
AI offers the capability to process vast amounts of data, identify patterns, and make predictions with a level of speed and accuracy unattainable by traditional methods. This has profound implications for mechanical engineering, enabling more efficient design processes, predictive maintenance strategies, and optimized manufacturing operations. AI-driven tools can learn from historical data, adapt to new information, and continuously improve their performance, making them invaluable in tackling the multifaceted challenges of modern mechanical engineering.
Advanced control scheme of doubly fed induction generator for wind turbine us...IJECEIAES
This paper describes a speed control device for generating electrical energy on an electricity network based on the doubly fed induction generator (DFIG) used for wind power conversion systems. At first, a double-fed induction generator model was constructed. A control law is formulated to govern the flow of energy between the stator of a DFIG and the energy network using three types of controllers: proportional integral (PI), sliding mode controller (SMC) and second order sliding mode controller (SOSMC). Their different results in terms of power reference tracking, reaction to unexpected speed fluctuations, sensitivity to perturbations, and resilience against machine parameter alterations are compared. MATLAB/Simulink was used to conduct the simulations for the preceding study. Multiple simulations have shown very satisfying results, and the investigations demonstrate the efficacy and power-enhancing capabilities of the suggested control system.
Introduction- e - waste – definition - sources of e-waste– hazardous substances in e-waste - effects of e-waste on environment and human health- need for e-waste management– e-waste handling rules - waste minimization techniques for managing e-waste – recycling of e-waste - disposal treatment methods of e- waste – mechanism of extraction of precious metal from leaching solution-global Scenario of E-waste – E-waste in India- case studies.
artificial intelligence and data science contents.pptxGauravCar
What is artificial intelligence? Artificial intelligence is the ability of a computer or computer-controlled robot to perform tasks that are commonly associated with the intellectual processes characteristic of humans, such as the ability to reason.
› ...
Artificial intelligence (AI) | Definitio
2. Introduction
My name is Harry van der Veen, callsign Gravano.
I’m a 25 year old Communication & Multimedia Design student, located at the NHL (Noordelijke
Hogeschool Leeuwarden) in Leeuwarden (Holland), participating in the fourth and final year of that
education.
I’m writing this FTIR multi-touch display how-to guide, because I want to make it easier for other
people to build their own multi-touch display.
My intensions are to make this guide understandable for people, in the age of approximately twelve to
about seventy years.
I would like to point out, that in this guide, I describe “a way” to build a multi-touch display. I’m not
saying it’s THE way. There are numerous of ways to build screens, this is just one of them.
There’s nothing you should know about any difficult technologies. I’ll try to explain everything as
simple and thorough as possible.
Only thing you must be able to is, actually buy or own the materials and have some basic handyman’s
work skills like drilling, sanding, sawing, polish. If have two left hands myself and even I succeeded, so
you should be fine.
After walking through this guide, you should be able to understand the technology behind this project
and be able to build your own multi-touch display, to let it collaborate with your own computer.
This is only possible with the appropriate software.
Only the hardware is discussed in this guide.
There’s the possibility, to write your own software for the multi-touch display.
This however, is a whole different aspect. Which as mentioned above, is not discussed on this paper.
When finished with this guide, you’ll have a general understanding of why which materials are being
used and what the alternatives are.
By this way I would also like to thank everybody from the NUIgroup (Natural User Interface) open
source multi touch community, for all their efforts and contributions.
I hope you enjoy this guide and that you have a working multi-touch display as well in no time, so you
can collaborate with us inside our community.
If you have any questions or suggestions, feel free to contact me at harryvdveen@gmail.com
If you’re looking for more information regarding this subject, visit our community
Blog: http://www.nuigroup.com
Wiki http://www.nuigroup.com/wiki/
Forum http://www.nuigroup.com/forums/
Join us on irc.freenode.net on #ftir
Or drop by on my personal blog, located at: http://www.multitouch.nl
3. Table of contents
Introduction.........................................................................................................................................2
Table of contents ................................................................................................................................3
Requirements .....................................................................................................................................4
Tools...............................................................................................................................................4
Building materials............................................................................................................................4
Software..........................................................................................................................................4
Technology explanation ......................................................................................................................5
Global building process.......................................................................................................................6
Modifying a webcam........................................................................................................................6
Treating acrylic................................................................................................................................6
Building a frame ..............................................................................................................................6
Wiring an electronic circuit...............................................................................................................6
Projection........................................................................................................................................6
Detailed building process / material information...................................................................................7
Modifying a webcam........................................................................................................................7
Treating acrylic..............................................................................................................................12
Building a frame ............................................................................................................................15
Wiring an electronic circuit.............................................................................................................19
Projection......................................................................................................................................26
Projection screen material..........................................................................................................26
Silicone rubber...........................................................................................................................27
Projector....................................................................................................................................30
4. Requirements
Tools
Power drill + 5mm drill
Standard size screwdriver (flathead & cross)
Small sharp knife
Scissors
Different grits of sanding paper
Wooden cubical object to wrap sanding paper around
Copper or silver polish + towel
Synthetic material saw
Building materials
Screws € 5
Glue (hotglue / white glue) € 10
Frame material (for example wood, aluminium or PVC) € 5 (depends on construction)
Connector strips € 5
Electronic wire (0,5 mm) € 5
IR-LEDs + resistors € 30
Acrylic also known as plexiglas € 25
Black photo negatives € 5
Power source € 10
Power cable € 5
Webcam € 15
Projector € 200+
Projection material (tracing paper) € 5
Silicone rubber € unknown (35 max)
Working computer
Mirror (optionally)
So basically the projector is the most expansive part of the device. You can make a multi touch display
without a projector and use your monitor as an output, which is like totally not cool ;)
So for an amount of about € 350, you’ll be able to build a cool multi touch display.
You could also go with a more expansive webcam, filter or projection material, for better performance,
but for the proof of concept, this will do.
Software
Computer applications are necessary to communicate between a multi touch display and a computer.
These applications can be developed within several languages / programming environments.
For example: Processing (P5), VVVV, Flash, C, C++, Java and others.
Because of the usability of certain API’s and the relatively simple visualisation possibilities, I reckon
P5, VVVV or Flash 9, in combination with Actionscript 3.0.
The above can be downloaded from the following locations:
Processing (P5) - http://www.processing.org
VVVV - http://www.vvvv.org
Adobe Flash 9 - http://www.adobe.com/nl/downloads/
Applications built within these API’s, are freely available, on the forum of the online Open Source
Multi-touch Community, called NUIgroup (Natural User Interface), located at:
http://www.nuigroup.com/forums/
6. Global building process
The building process consists of the following 5 main elements
Modifying a webcam
A normal webcam will be modified to a webcam that can detect IR-light.
The IR-block filter inside the webcam will be replaced by an IR-pass filter.
Treating acrylic
The treatment of the acrylic will be discussed.
Our main objectives will be sawing, sanding and polishing.
Building a frame
The build of a frame will be mentioned. What material to use etcetera.
Wiring an electronic circuit
There will be an explanation about how to creat an electronic circuit containing LEDs, resistors, power
supply and wires.
Projection
Here you will find information on what kind of projection material and beamer you can use and how to
make a silicone rubber sheet as a coupling layer between the acrylic and the projection screen.
7. Detailed building process / material information
Modifying a webcam
Needed material:
• webcam
• lens
• black photo negative
• tape, glue or any other material that can hold the black photo negative in place
Modification of a webcam is necessary to detect the IR blobs that are generated by your fingers. IR is
not visible to the human eye, neither is it to most of the webcams. Some webcam’s detect IR, but not
as clear as it should be, for this project.
Every webcam can detect IR, but this option is not available because, there’s an IR-block filter inside
the webcam that blocks IR. So the camera is able to detect all visible light, but not the IR.
To see to it, that the webcam detects the IR, we need to remove the IR-block filter from the webcam.
So it will detect all visible light including IR.
For removing this IR-block filter, we have two options:
• removing the IR-block filter manually
• replace the current lens with another lens that has no IR-block filter
With some webcams it’s relatively easy to remove the IR-block filter.
For my first multi touch display, I used a cheap (€ 10/15) Sweex webcam (Sweex WC001 webcam),
that had a IR-block filter in front of the lens.I broke the IR-block filter (some sort of glas material), so I
could remove it.
Image 2: A Sweex WC001 webcam
In some cases the IR-block filter is painted on the lens and you can scratch it off.
But be careful that you don’t leave scratches on the lens.
But in most cases, it’s impossible to remove the IR-block filter, without damaging the lens, because it’s
glued to the lens.
In that case, it’s wise to replace the default lens with a special lens that doesn’t have a IR-block filter
attached to it. Try to find a lens that looks like the one below.
8. Image 3 : The 4.3MM CCTV Camera board Lens IR DVR
Lens specifications:
• Glass Lens
• Aperture F/1.8
• Image format 1/3 inch
• Angel of view 68°
• M12x0.5 mount
• Size ?14×14.75
$14.99 + $8.50 (shipping) = $23.49 total
In my example, I used a Philips SPC900NC webcam, which has a difficult to remove IR-block filter
attached to the lens. That’s why I choose to buy and replace the default lens, with a special lens, from
ebay, without IR-block filter. It’s a 4.3MM CCTV Camera board Lens IR DVR.
Image 4 : The 4.3MM CCTV Camera board Lens IR DVR without IR-block filter and Philips
SPC900NC webcam.
9. Onces the webcam is modified to being able to see normal light as well as IR-light, you need to apply
an IR-pass filter. This IR-pass filter, lets all the IR through, but blocks out most of the visible light.
There are different materials that you can use for this purpose:
• IR-pass filter
• IR-band pass filter
• Remote control filter
• Black photo negatives
IR-pass filter
Image 5: An IR-pass filter
An IR-pass filter is a special filter that only passes through IR on a certain frequency (760 nm to for
example 1000 nm). So it basically blocks out all other light, that’s not within that region, that would be
most of the visible light.
IR-band pass filter
Image 6: An IR-band pass filter
The IR-band pass filter only passes through IR on a specific frequency.
For example: 880 (nm)
So if you’ll use 880 (nm) IR-LEDs and you use an IR-band pass filter of 880 (nm) as well, you’ll get the
best optical performance, because all the light is blocked out, except for the specific IR from the LEDs.
I haven’t tested the IR-pass filter nor the IR-band pass filter, because they are relatively expansive. 80
euro for a IR-band pass filter. But from what I’ve heard, they work very well.
The IR-band pass filter works better then the IR-pass filter.
Which will hopefully make sense after what I’ve wrote just above.
10. Remote control IR filter
Image 7: The front of a remote control
The filter on the front of remote controls (deep dark red/black piece) isn’t very handy to work with,
because of the different shapes it may have and the result is almost the same as one layer of dark
photo negative.
Black photo negatives
Image 8: Photo negatives
So because of a low budget scenario and usability, I reckon you use several layers of entirely black
photo negatives. You’ll probably know them. They are usually among the negatives of your holiday
pictures etcetera. It’s those completely dark negatives that appear when pictures are misfabricated.
Three layers will do the job nicely. If you use too many layers, your blobs become less visible as well.
Attach them in front of your lens.
First you have removed the IR-block filter and then you applied an IR-pass filter.
The webcam modification is finished.
You can test your camera by pointing at a money bill or cola.
Or by checking if it detects the IR-light from a remote control.
11. Image 9: 50 euro in infrared
Image 10: Cola is transparent in infrared
12. Treating acrylic
You’ll need the following materials:
• Acrylic also known as Plexiglass
• Sanding paper (for example: grit 100, 200, 400, 600)
• Wooden cubical object to wrap sanding paper around
• Copper or silver polish + towel
• Synthetic material saw
Acrylic will be the material that internally reflects the IR-light.
This material is strong and works very well as an optical waveguide.
You could also use polycarbonate, which has a plus compaired to acrylic, namely it’s unbreakable.
But the optical waveguide performance is a few percent worse.
You can get acrylic at glass stores, but I found out, that most of the time, you pay ten times the
amount, compaired to buying it online. So I suggest you buy it online from ebay or equivalent.
If you can get it cheap from a glass store or a handy man’s shop, go and ask if they can cut the acrylic
in the dimensions you desire, so you don’t have to cut or saw it yourself.
In most cases, they can even buff the edges transparent, so you don’t have to treat your acrylic at all
and you can continue with the next step: Building a frame.
Most of the time, acrylic has transparent cut edges when it leaves the factory.
Most people I know made 4:3 ratio multi touch displays. So unless you are going to use a 16:9 ratio
projector, to project your image, I suggest you cut your acrylic with a 4:3 ratio as well.
I bought a piece of acrylic (dimensions: 460*900*8 mm) for about 25 euro’s from
http://www.marktplaats.nl (a dutch equivalent of ebay).
I sawed off my piece from that bigger piece. Sizes: 460*320 mm (4:3 ratio) 8mm thick.
8 mm thick is the least you should go with, because the LED’s you’re going place along the edges,
will be 5 mm thick. Especially if you’re building larger screens, you want to go with a thicker piece,
because it needs to be robust. So even when, you push in the middle, the acrylic doesn’t bounce.
If you need to saw your acrylic yourself, at least use the finest saw you can find,
so you can try and keep the edges as smooth as possible.
If there’s a protective film material on the acrylic, keep it on as long as possible, so you’ll prevent the
acrylic from being scratched.
13. Image 11: Transparent acrylic with protective film material, square piece of wood, sanding
paper
If you have sanding tools, I suggest you use them, instead of doing it by hand.
Make the edges of the acrylic as transparent as possible, to increase the amount of IR-light beamed
into the acrylic
Try to find the highest grits of sanding paper. I believe there’s even grit 2000 sanding paper.
Higher grit > finer scratches > better transparency
Wrap the sanding paper around a piece of flat wood, to prevent round and to ensure flat edges
Start off sanding with a low grit sandpaper
Increase the grit step by step (for example 100, 200, 400, 800)
When using the highest grit sandpaper, put olive oil or equivalent, on the edges and continue sanding
Finish the edges by polishing them with copper or silver polish and a towel
When finished, the edges should be pretty transparent.
I sanded all four edges, eventough I’m going to place leds along two sides. This because I want, light
that bounces out of the sides, to be able to bounce back easily through the aluminum that I will put
along the edges.
I namely experienced IR-light leakage on the sides during my first prototype. That’s why I want to
bounce the light back into the acrylic.
14. I decided not to flame polish the edges afterwards, because I thought the edges were already
transparent enough and you don’t want to accidentely destroy parts of your acrylic.
Because, when you flamepolish them wrong, you might create small air bubbles, inside the acrylic or it
might turn out black.
15. Building a frame
During the build of the first proto I found out that I wanted some kind of reflective material against the
edges to bounce back leaking IR light. With my first proto I used aluminum tape, but it intends to stick
to everything, so basically alot of annoyance.
Image 12: Acrylic in aluminum frame (mount in progress)
So I decided to make an aluminum frame around the acrylic, which can also hold the leds at the same
time. It makes your screen look alot better then with shabby tape hanging around.
16. Image 13: Acrylic mounted in aluminum frame
I used 4 pieces of aluminum rail. 2*50 cm and 2*38 cm both 10 mm (acrylic= 36 * 48 cm, 8mm thick)
So the acrylic would stuck inside the aluminum rail perfectly, it seemed it first. Lateron I founded that
the rail on one side was a little hard to get around the acrylic, so I used brute force with a hammer.
I sawed of the edges of the aluminum with a 45 degree angle, so they would perfectly fit against
eachother.
Afterwards I drolled 5mm holes in the 2 rails that will hold the leds. 10 holes on each rail. I choose
5mm holes so the leds would get stuck pretty good, since the leds theirselves are also 5mm.
17. Image 14: Drilled holes in aluminum U-frame
Image 15: Drilled holes in aluminum U-frame
Then I placed the leds in the holes to see if I had the wished for result.
18. Image 16: Leds put through the drilled holes in the aluminum U-frame
Because of the space inside the aluminum, there’s just enough room to hold the head of the led.
Image 17: Wooden frame around the aluminum framed acrylic
19. My wooden frame has arrived. My uncle makes wooden frames for paintings and since they only cost
5 euro I asked him if he could make one for me. The acrylic/aluminum part leans on the wooden frame
on the left and the right side and a little bit on the top and the bottom as well. Notice I have space left
on the bottom and the top side to wire the leds and resistors.
Wiring an electronic circuit
Imag 18: IR led powered by a 5 volt USB connection
LEDs (Light Emitting Diodes) need a power source to produce light.
There are several ways to power your LEDs. For example by batteries (1,5 volt), USB (5 volt) or a 12
volt adapter. But you could also connect your led’s to the 12 volt molex connector on a computer
power supply.
I used 100 (mA) miliampère LEDs, so I needed a pretty good power source.
Using batteries doesn’t make alot of sense, since you would need quite a few and you would need alot
of wire as well, because of the inefficient power circuits.
Using USB is possible, but I would only choose that option, if you are going to use 20/30 (mA) led’s
and even than, a computer power supply would make more sense, since you can put more led’s in a
row.
Why not use a computer powersupply? Your screen is going to be near a 220 volt power source
anyway, since you have to use a projector and a computer as well.
You can use one of the molex connectors on the computer you are working on, to supply the leds with
power. But you could also use it without the motherboard in between.
20. Image 19: 6 IR leds powered by a 12 volt molex connector inside a computer
There’s a pretty easy solution to hotwire a computer power supply.
If you look at the ATX connector, you see several colored wires:
Image 20: ATX connector
To hotwire your computer power supply, simply connect the green wire with any black wire (ground) of
the pin out and you will be able to connect your LEDs to one of the molex connectors, without the help
of a motherboard, turning the power supply on.
During the build of my first prototype I used 36 880nm 60 degree 5mm cl IR leds (1,8 V, 20 mA, 11,0
mW/sr).
Lateron I discovered that there were leds that were even better, namely the Osram SFH485,
specifications: 1.5 V 100(mA) 880 (nm) 5mm. These were a bit more expansive but more powerful, so
I would be able to use less leds.
21. Image 21: An Osram SFH485 IR LED
I decided to go with 10 leds on both horizontal sides, so 20 leds in total.
After filling in the specifications of the power source and the leds in this led wizard , I found out that, I
had to make 4 strings of 5 leds, each with a 47 Ohm resistor of 1 Watt. An electronics teacher at
school gave me a few 51 Ohm resistors of 4 or 5 Watt. He told me that would do the job pretty well,
since the higher Watt was only about the amount of heat that a resistor could handle. So it would just
handle an higher amount of heat without influencing the brightness of the leds. And the difference of 4
Ohm (51-47) was not noticeable, according to him.
22. Image 22: 6 connected leds for testing purposes. Green thing in the lower left corner is a
resistor.
Image 23: 6 connected leds for testing purposes
23. I connected the leds on 2 different molex connectors (12 volt), but I might as well have gotten around
with just using one.
I just happened to have 2 molex connectors, so I used 2 (which is pretty useless actually).
The wires I used were pretty short, so you might want to use longer ones, so it will be more flexible. I
used 0,5 mm thick wire.
I did the entire circuit without soldering, for a change, which seemed to work just fine. So why spend a
lot of time on soldering if you can do without.
Image 24: Front of screen
24. Image 25: Back of screen
I connected the leds with each other by using strip connectors (”kroonsteentjes” in Dutch).
My first intention was to do the entire setup without the strip connectors and just let the holes in the
aluminum rail hold the leds. But because of the fact that some holes were a bit to big (matter of tens of
a millimeter) to hold the leds pretty steady, I decided to use the strips anyway, because else the leds
would be too loose.
You might as well go for the solution below, which is a solderless ledholder. You can easily click the
led into this holder, so you won’t be bothered with soldering anything.
Image 26: Solderless led holder
After connecting all the leds I tested the entire setup by checking for fingers on the computer (image
below).
Which seemed to work pretty fine.
25. Image 27: hand placed on screen, detected by webcam, displayed on monitor, power supplied
by computer power supply (molex 12 volt)
Note:
With most leds the longest pin of the led, is the plus and the short one is the minus.
But with these leds (Osram sfh485) it was the other way around.
26. Projection
To project the image from a computer, you’ll need a projector and a projection screen.
The projector beams an image on a projection screen, that is placed underneath or on top of the
acrylic.
A plus of placing the projection screen material on top of the acrylic is that you can directy interact with
the image. There is no visual imperfection contrary to placing the projection material underneath the
acrylic. If you place it underneath the acrylic you’ll still have to optical difference of the thickness of the
acrylic. In this case you can also let the projection screen function as an ambient IR block filter, but
more about this lateron.
In case you want a closed box solution for your multi touch, you may want to consider using a mirror to
reflect the image that comes from the projector, so you can shorten the distance. Keep in mind that
there can be ghosts images (vague double projections), caused by the acrylic bouncing back the
image to the mirror and back to the acrylic again.
Projection screen material
There are different materials you can use as a projection screen:
• Rosco grey rear projection screen
• Mylar
• Tracing paper
And I bet there are tons of other materials you can project on. For the project I did in Sweden we used
some kind of white plastic paper material which they use to make designer lamps.
Rosco grey is a very good projection screen, but it blocks IR, and it therefor diffuses the blobs, if you
place it underneath the acrylic, and makes them rather unusable for software analysis.
If you place it on top of the acrylic the blobs are a bit less vague, but still very diffuse, because there’s
no good coupling between the acrylic and the Rosco.
Furthermore Rosco is relatively expansive compaired to the other two materials.
Image 28: Piece of Rosco grey on top of my first prototype
The cheapest solution is tracing paper.
27. But since you want your multitouch display to work in all kinds of environments, don’t want ambient
infrared light to interfere with it. Therefor you have to use a projection material on top of the acrylic that
blocks IR. Rosco grey is one of those rear projection screen materials.
Silicone rubber
The problem with placing the rosco grey on the bare acrylic is, that it hardly generates usable blobs.
The blobs are pretty vague because of the bad coupling between the acrylic and the projection
material.
You have to press pretty hard to generate a workable blob. And that’s not something you want. This
has to do with physics. It’s about relative index of refraction. For example, when you touch the acrylic
with your bare fingers, there is still some miniscule air in the space between the acrylic and your
fingers. So when you wetten your fingers, these miniscule air holes get filled, so your finger has a
better coupling with the acrylic. This way the blobs are brighter with wett fingers opossed to dry
fingers. Therefor we needed to find a material that prevented those small airholes as much as
possible, so that there would be a better coupling, resulting in brighter more clear blobs.
A lot of people within the NUIgroup community have experimented with different materials and we got
pushed in the direction of silicone rubber being the best solution to this problem.
Here at the university in Sweden we made two samples of silicone rubbers sheets, a 1mm and a 2mm
thick. The 1mm thick sample worked better, since the blobs were brighter. We haven’t tried thinner
sheets, but 0,5 mm may even work better. But that’s all up to you if you want to experiment with that.
Material details
The silicone rubber sheet we prepared are made out of 2 fluids that you combine and then they cure
over time. The fluids come from a company named Wacker Chemie AG. Their website is located here:
http://www.wacker.com
This company only sells these products in amounts of 20 kg’s. But since we are doing research for
Lulea University of Technology (Sweden), we have a supplier that cuts the 20 kg amounts into smaller
pieces. So we were able to order just one kg.
The company that divided the 20 kg’s into smaller amounts, is called ABIC Kemi.
The brand of fluids we used go by the name of ELASTOSIL® M 4641.
ELASTOSIL® M 4641 is a pourable, addition-curing, two-part silicone rubber that cures at room
temperature.
Special characteristics
• Very good flow properties
• Fast and non-shrink cure at room temperature which can be accelerated considerably by the
application of heat
• Medium hardness (Shore A approx. 43)
• Good transparency of the cured rubber
• High tear strength
• Outstanding resistance to casting resins, particularly polyurethanes and epoxies, for long
service life of the molds
You can download a PDF with more specifications here. (English version)
Or download a German version, here.
28. Making a silicone rubber sheet
• First you have to make a frame of some kind that will hold the acrylic in place and that has
some kind of border that is 1 mm higher then the height if the acrylic, when you placed it in the
frame.
• Then you have to decide on how much silicone rubber you want to use.
• Afterwards you weigh andmix the two components and stir them until they are properly mixed.
• Pour the silicone rubber liquid onto the acrylic and devide it with an object (a plastic knife or
so).
• Immediately when you equally divided the liquid, flatten it by using a strip of material
(preferable NOT metal, PVC might work)
• Now let it cure several hours (14 hours with our liquid).
The longer the curing process the smaller the chance of bubbles in the silicone rubber sheet. We
didn’t have any bubbles anyway on our 1mm thick piece.
Make sure you let it cure in a place that’s not very dusty or cover the setup while curing.
Image 29: Pouring the silicone rubber liquid onto the bare acrylic
29. Image 30: Dividing the silicone rubber over the entire acrylic surface
Image 31: Flatten the silicone rubber surface with a strip
Now the silicone rubber sheet that’s placed between the acrylic and the projection screen material is
finished. Now just cover it with a piece of projection material and you should be good to go. Make
sure you test what side of the projection material up, creates brighter blobs, there’s a difference!
With the Rosco one side on top is different to the other side on top.
30. The layering is like this:
Acrylic with the silicone rubber sheet on top of that. On top of the silicone rubber sheet you place a
projection screen. Make sure the projection screen doesn’t stick to the silicone rubber sheet, because
otherwise the ftir effect will be set off.
So basically it looks like this:
———- your fingers
———- projection screen
———- silicone rubber sheet
———- acrylic
———- image source
Projector
What kind of projector you want to use, is all up to you.
You can choose a HD-projector, LED-projector or even a 16:9 projector.
But keep in mind, that with this guide I used a “normal” 4:3 ratio projector.
You don’t have to use a projector. You could also just go with the entire setup without projector and
projection screen and navigate with the multi-touch display and look at the output on the monitor of
your computer.
In case you want to work with a projector and don’t have enough room to properly project the image
on the projection screen. You might want to use a mirror to redirect the image.
Image 32: Redirecting the beamed image with a mirror.