Category Archives: electronics

Dropbox and Syncing all your photos to your Galaxy S4

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A few months ago I got my hands on a Samsung Galaxy S4. As part of the setup procedure it asks for your login details for Dropbox, this was great, I actively use Dropbox, had the app on my previous phone and regularly access files from my cellphone. As it was set-up on my previous phone to only download files when I request/access them, I expected the same to happen with this setup.

http://www.talkandroid.com

http://www.talkandroid.com

The next day I checked my gallery, and saw hundreds and hundreds of photos that Dropbox had decided I wanted to have on my phone. Fortunately I was on Wi-Fi, otherwise that 1.5Gb could have hurt my phone bill at the end of the month. This wasn’t a major problem, as I assumed I’d missed something in my settings which told it to sync photos, so I went in search of the correct settings. And I couldn’t find them anywhere.

I compared the settings exactly to that on my previous Android phone and there was no difference. After searching for a quite a while on the internet, I eventually came across a forum post that explained my problem. The setting I was looking for wasn’t in Dropbox, it was in my phones ‘Accounts’ options, and not under the Dropbox account, but under the general ‘Cloud’ options.

If you look at the bottom you’ll see a ‘Contents sync (with Dropbox) menu, here you can disable the syncing of pictures, videos and documents. Disabling this option then removed all my photos from my gallery and prevented the further unwanted syncing of files from Dropbox to my phone.

So to get there:

Settings > Accounts tab > Cloud > Contents sync

Master’s Update

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So after an amazing three months in Germany, I had to come back to the real world and finish off a Master’s Dissertation.

I got back to PE mid-December and had a week to finish off my testing before I left for the Cape for two weeks. I then had five more days in PE before I had to hand in my dissertation. Final hand-in date to still qualify for April graduation was 11 January, handing in after that date would mean I’d have to reregister for another year of studies, and would probably result in me doing a whole lot more work, not necessarily a bad thing.

But with 3 days to go I was still doing testing. Below you can see a clip I compiled of said testing. In the end I handed in a dissertation in time. Most of it had gone through a round of editing by both my gran and girlfriend, with slight input from my supervisor. I wasn’t completely happy with what I’d handed in, and could have done with another month to neaten up the report, read through it properly and get some proper feedback from my supervisor, but such is life, and what is done is done.

In any case, the following week I did a demonstration for the project initiators who were quite happy with the results and it will most likely be taken forward. There’s a second master’s project on the table which will be extending on my work, but the company in question are going to take the design to contractors with the plan of getting a commercial unit up and running. Exciting stuff, my supervisor was also quite happy and said from his side he doesn’t think there’ll be any problems, so know I just sit and wait for results from the external. If I hear before the end of March I’ll be surprised, but don’t know when I should start bugging my supervisor for answers :)

In the mean time I’ve moved another step further from the Cape to the city of East London where I’ve got an appointment at a large manufacturing plant for the next year. The work ought to be quite interesting as the factory’s busy with a rebuild, but it’ll be interesting to see where it goes.

Once I’ve had feedback on my master’s and have made any necessary changes I’ll put my full thesis up. I also have to write up a journal type article on the project so will post that whenever I get round to finishing it. In the mean time you can see my previous post on the project here.

Research Work

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As part of my time spent in Reutlingen I did some reasearch work for Prof. Dr -Ing Gruhler of the Mechatronics Department of the Hochschule Reutlingen. I ended up compiling two reports. The first was a purely research based one and the second included some practical work on a mobile robot. The work on the second report was used in a journal article available here.

Summary of Omni-Directional Drive Choices

This report briefly introduces the concept of an  omni-directional drive. It then proceeds to give overviews of many of the the currently available and in use methods of achieving omni-directional drive. Both units which have received commercial use, and those restricted to hobby robotics have been listed. Because no specific application was in mind, no recommendation towards a specific drive method was made. The appendix includes some further information and links to a design report and video demonstration of most of the drive methods listed in the report.

Drive types mentioned include: Omni-Wheels, Anisotropic Wheels, Omni-Ball, Mecanum Wheel, Swerve Drive, Ball Drive, Vuton Tracks, Omni-Crawler, Hemispherical Gimbaled.

The report can be downloaded here (4.5 MB PDF)

Notes on Robot Odometry

In this report a pre-built omnidirectional robot is  modified to allow for better odometry as well as control. The report investigates several possibilities for odometry, and then making use of available equipment adds a proximity sensor to the robot for accurate tracking. In addition to this the movement control code is replaced with PID controllers for both directions of movement. Slight adjustments are made to the visual interface with the robot and a Wi-Fi connection is re-established.

The full report can be downloaded here (2.1 MB PDF)

Autonomous Guided Vehicle Master’s Project

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In February this year I started work on my MEng Mechatronics degree at NMMU in Port Elizabeth. The current title for the project is “The Design of a Low-Cost Autonomous Guided Cart (AGC) for Material Handling”. The project was initially suggested through a collaboration of my department and the General Motors factory in PE.

I’ve barely posted any details during the year, I’m never quite sure where I stand with IP, as far as I know I own none of it, and the university owns it all. In any case, as part of the South African Automotive Week held in Port Elizabeth this week, our department had a stand and apparently a video similar to what can be seen below is on show there. I feel that’s more than enough to cover me posting the video here.

There are similar products available on the market, but they are very costly, I’m aiming at my product being less than R30,000 (US$3,500) per unit. Obviously this is a pure cost per unit value, and doesn’t take into account development costs that a normal project would invoke.

There were a list of specifications that had to be met, I’ll post my thesis early next year some time, as with any project, but the budget was definitely the limiting factor. There are lots of nice toys you can put into such a project, such as an R11,000 (cheapest I could find) laser range finder, alas. Finding suitable motors and drivers is also rather tricky.

I initially (and still do) wanted to use a microcontroller. After discussion with several staff members I was pretty much instructed to use a PLC. I understand that the application lends itself to PLCs, but I’m far more comfortable with microcontroller and the cost cutting effect would be significant.

In any case, the video shows some of the testing I did at the GM factory. Control is a bit iffy at the moment, I didn’t research my PLC choice well enough before selecting it. I have a few ideas in mind to improve this, unfortunately I’m in Germany till mid-December (well not really unfortunately) so I’m only going to have a week or two to make changes to my AGV before I have to hand in my thesis.