Tag Archives: accessible

Building a cheap book scanner – Progress Report 3

Abstract

A first prototype of scanner was presented in our last post, a different fixing system for the scanner has been designed since and a lightning system has been added to the prototype. Since, the last post, our programming team has also started working on the app itself.

Hardware

Scanner fixation

The first prototype had to be attached to a table. To make the scanner use more flexible and to be able to use it anywhere without any risk of damaging the table, a stable base for it has been designed. This base is made with small pieces of wood, making it rather light. To ensure an easy storage and transportation of the scanner, the base was also designed to be foldable. This was achieved using hinges and an elastics system to keep it opened.

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Former fixation system

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Foldable base

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Elastic system to hold the bas opened                                                      Hinges

Lightning system

One of the most important parameters for pictures quality is the lightning. It was therefore important to find a way to have a good lightening on the whole book, without any shadowing and while keeping in mind our first objective, the lowest possible price. Tests were done using a 4.90 CHF halogen lamp fixed on the scanner a bit under the phone fixation; more tests have to be done to choose the final positioning of the light. We might have to use two of them to ensure a good lightening everywhere.

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Scanner with lightening device

Software

Methodology

The app is coded using XML and Java on Android Studio. The first problem our programming team encountered was how they were going to be able to work simultaneously on the program. After some research, they found the Google Cloud platform which allowed them to do so.

What will the app do?

It will ask the user to reshape the first page, store the settings and then apply it to all the following pages. Once fully scanned, the book will be exported to PDF. The user will have to fix the settings for the first page, turn the pages and use the pedal to tell the app when to take a picture. It will be possible to either continue a project (book) that was started but not finished or to start a new one. It will also be possible to rescan some pages if the user is not satisfied with them.

The interface

When opening the app, the user will arrive on a page on which his different projects will be listed. He will be able to manage, edit or continue existing projects or to start a new one.

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App Interface

First problem encountered

The first version of the app is using the already existing camera application. This will have to be changed because when with this app, the user is asked to confirm each picture before he can take the next one, which obviously is a problem as we want to have a fluid scanning process. We will therefore have to implement our own algorithm to manage the camera directly in the app, which requires a lot of time.

What’s next?

In the oncoming weeks, our programming team will go on with the app, starting with the camera issue. They will then have to figure out how to use the Bluetooth pedal to take the pictures, do the settings on the first picture and apply it to all pictures and manage the different projects.

The scanner prototype will be further improved, the lightening question will be solved and other tests will be carried out.