Chrome extensions offer a very limited range of ways to interact with the browser while Firefox allows for complete customisation, because of this Firefox extensions are developed in a much more complex but powerful way.

The Firefox extension can be downloaded from here https://addons.mozilla.org/en-US/firefox/addon/107869 its currently waiting for a Mozilla person to check it before it will loose its experimental status.

The extension uses the same script as the chrome extension to display the contact information; the sample code I used for this is limited so I have spent the past week working on a new script. Its taken me longer than it should have and i still haven’t done but the new script should display the tel info in a much better way, it will also allow me to make updates and changes as new features get added to the specification.

If anyone does give it a try and finds any problems please let me know in the comments.

Also, if anyone is looking at developing a Firefox extension I found this blog post very helpful http://blog.mozilla.com/addons/2009/01/28/how-to-develop-a-firefox-extension/

I had decided on the framework but needed an idea for a website, I turned to my girlfriend for suggestions and she came back with ‘happy’, as you probably imagine I looked a little puzzled.
Despite being an odd topic I came up with the idea of a social aggregation site around the topic of happiness.

It took an evening but I came up with a very basic, one page site that displayed twitter posts and flickr images all related to the topic happy, the next evening I added a couple more pages to narrow the range to just text, photos or videos.

You can see the site I came up with here, happy.arthurguy.co.uk

This was a very basic site but it was a nice introduction to the framework and how easy it is to deal with, I especially like the automatic url structure, rather then messing around with htaccess files to get the address looking nice it happens automatically.

Earlier in the week I took a look at the extensions developer guide and was surprised at how simple making an extension appeared to be, I had been updating my .tel domain the previous day so I cam up with the idea for an extension which would scan a page for a .tel address and display the associated contact information.

I used the Mappy sample extension as a starting point as it offered similar functionality; after getting the code to identify and return a .tel address I moved onto displaying the .tel information.
This was harder than I was expecting, all the contact information associated with a .tel address is stored in its DNS records so it can’t just be queried as you would a web service, thankfully Telnic provide some sample code so after spending an evening working with that I came up with a script which would display the contact details when passed a domain name.
At this point it was just a simple case of updating the extension to display the contact information in an iframe and it was done.

My extension can be found here – .tel Info Google Chrome Extension

I will hopefully port this to Firefox soon although there system is a lot more powerful and as a result more complicated.

Trip List, the site for managing trip signups

A few years ago when I was organising trips for the University mountaineering club and wanted a better way to collect peoples names for climbing weekends I decided to build the trip list application for Facebook. It took 2 days but I came up with a very usable application for setting up a trip and allowing people to sign up. After I finished my stint as social secretary for the club I forgot about the application and just left it to fend for itself.

I have recently decided to pursue a career as a freelance web developer so I decided to go back to the application to refresh my Facebook programming skills; I have spent a few hours over the past week improving the application and fixing a few issues that arose as a result of changes to the Facebook platform over the years. I have now finished and have an application that works well again.

It’s been fun working on Facebook again, it really is an easy platform to develop for. There are a number of quirks to get used to and things you can’t do and Facebook’s recent changes regarding messaging are an interesting change. They now don’t want applications contacting users through the site itself, they either need to email the user directly or they can place a number (think unread count) next to the application name in the sidebar. Both of these methods don’t seem ideal but I can see why they are making this change, in their eyes these changes are further separating the application and its identity from Facebook preventing annoying spammy apps from affecting the brand.

Home Office - Identity & Passport Service

There is a lot of debate surrounding privacy especially the identity cards, large groups are opposed to the idea of a national database containing contact and biometric details.
I am certainly not one of them, I can’t see the problem to a national database and I am amazed there isn’t one already, the UK has a lot of lists or databases across various departments each of which contains a selection of the UK population but none of them contain a complete list. The National Identity Register will unfortunately add to this with another database but hopefully if it takes off and the Conservatives don’t get into power and scrap it it may eventually replace other databases and provide a single unified database.

If the National Identity Register does go ahead I would like to see some web based management and viewing for users. A lot of the worry is caused by the uncertainty people will have about who is viewing their information, there is an easy way to solve this. Every search or request for information by a government agency or business should be logged, this information should then be available for users to view. If you could log into a secure site and view all the information the government has on you as well as every company that has ever requested your information it would put people at ease.

I should get my card in a few weeks but I seriously doubt any kind of system for seeing what information is held on me is available or will be available for some time.

Land fenced off for new signage

A week or so ago small sections of land started getting fenced off around Sussex University campus where I study and work, attached to the fences were signs saying trenches were being dug for new signage. In relation to the few signs and maps scattered around campus at the moment a lot of new ones were going up so it seemed a little excessive, today I found a brief article explaining that a campus signage review had been carried out and new signs were being installed at a cost of £700,000.

This is a figure I think a lot of people would find over the top, especially for signs but it really depends on what the final result is.
If they are just going to be as simple as maps on a stick then I think it will be a waste of money but something like this is a fantastic opportunity for the university to do something great. Rather than just maps these could be interactive information points, computer terminals displaying the latest university information or serving location information and people finders. I am certain they won’t be anything like this but they could at least make them semi decent by using them to extend the poor wireless internet service available on campus. These information points are everywhere and it looks like most of them would have power for lighting so it would have been a great opportunity to add wireless repeaters to improve coverage.

The other issue with this is the cost, I imagine a large portion of the money would have been spent on the external audit of the current signage, why did this need to be external? A few years ago the university paid a company £2 million to come up with a new brand including colours, logos and a general look, this is a specialised thing requiring lots of skilled people and I believe the money was well spent, this current project doesn’t require a high skill level just a moderate level of competence which I hope anyone working at the university would have.
Anyone could have analyzed the current signage and come up with a new plan why did they have to waste money on an external audit especially at a time when the university is in financial trouble and needs to save a lot of money.

Hopefully they will start to go up soon and I can see what they are going to be like.

I haven’t worked this out yet so as I write this I genuinely don’t know if it is possible to construct one but I plan to work it out, considering both size, power and practicality.
I have seen devices on the market which do this type of thing but none do exactly what I want, my specifications are as follows

• Small – It needs to be small enough so it can be carried without much inconvenience
• Power – The battery needs to power the unit for at least 24 hours ideally longer
• Accuracy – The GPS needs to be accurate enough to pickup a signal wherever the device is placed on someone
• Frequency – The system needs to transmit its location in real time, this means a constant communications link and no stupid SMS systems.

The other requirement for this system is that I can build it, that means no (BGA) ball grid array devices but I can deal with pin pitches down to 0.1″.

The system will be composed of 4 main parts, GPS, communications module, processor and battery. I will look at the GPS first.

GPS

GPS devices require a lot of power, they average around 30-40 mA at 3.3V which is a lot of power for something that needs to run all day, there are also different types of antenna, the common ceramic one needs to be pointed up which isn’t very practical, they can work at other angles but they aren’t as sensitive, thankfully you can get helical antennas which don’t have orientation problems.

GPS with Helical antenna

The GPS to the right is a high performance GPS which should be ideal, the body is only 2.5cm by 2.5cm and it has a small connector which can be soldered to, unfortunately it draws up to 80mA which is way to high.

Lassen IQ GPS, top and bottom view

After another look I have found a GPS module, a Lassen IQ which draws 26mA at 3.3V which is much better, it doesn’t have a built in antenna but a simple ceramic one can be connected, this will need to be pointed up but I will probably have to compromise on that option. The module is about 3cm square.

The antenna also draws some power, I don’t have an exact figure but it may be up to 10mA

Communications

Telit GM862 GSM module

The other important part of the system is the communications module, I have recently used a GSM module from Telit with another project so I will see what they have that would be suitable for this.

Telit make some small devices but unfortunately they are all BGA devices, this means I will need to use the same size device I used for the other project, this was 4.5cm square. They also make a GSM module (the same size) with a built in GPS, I initially had difficulty dealing with this signal so I would prefer to avoid using this device.

The module I previously used, the GM862, draws 24mA at 3.8v normally and averages about 150mA during transmission.

Processor

The processor would be a small pic microcontroller from microchip, its power consumption would be negligible.

The Battery

This is the important part, I would use a 3.7V lithium-ion battery, this would power the GSM module directly and a 3.3V regulator would be used for the GPS module, the GSM module has a built in battery charger so it will deal with battery management.

The GPS module will draw about 36mA at 3.3v, this works out out be 120mW of power.
The GSM module would draw 570mW assuming continual transmission.
These two together come to 690mW which can be rounded up to 700mW.

To run for 24 hours the battery would need to be at least a 4.5 Ah battery, this is large but not big enough to be impractical.

Size

The biggest part of this system is the GSM module at 4.5cm square, the GPS module could be placed to one side of this and the voltage regulator and capacitor in the 1.5cm by 3cm gap next to it, the microcontroller can go on the other side of the board and the battery would sit flat next to the board.
The battery would probably be about 1cm thick when you connect enough up to provide the power required, the GPS and GSM modules with the circuit board are about 1cm as well.
The GPS antenna can sit at right angles at one end of the board, this would add 5-10mm to the length and should be within the 2cm depth of the system, the GSM antenna is a piece of pcb and can attach to the side adding negligible thickness.
Overall the system would be about 8.5cm x 5cm x 2cm.

Conclusion

It seems a personal tracking system would be feasible, I could make something that could be clipped to a belt or kept in a pocket, it would need to be charged every day but it would transmit its location in real time.

With technology as it is it’s unlikely I would attempt this, maybe in a few years when the power consumption of GPS systems has dropped further or battery technologies have improved.

I use a regular GPS system quite a lot and a while ago I noticed that the speed it was reporting was different to what my car was reporting, the difference was fairly big at high speeds, for example driving at 70 mph the car reports it as 76 mph. It was at that point I thought it would be a good idea to have a digital speedo which used a GPS system to calculate the speed. I looked around and found a system which offered this, it was a small box which sat on the dashboard and projected the speed onto the windshield as a head up display; I can’t remember the exact price but it was around £50, not to expensive but not worth it for something unimportant.

That was a year or two ago, recently I was looking at GPS modules online and decided it would be fun to make my own, with that in mind I devised the following system.
My GPS system would consist of 3 parts, the main GPS unit, a speed display and a tracking system.

Main GPS

The main unit would house a high sensitivity GPS unit (LS20031), a microcontroller (PIC 18F2620) and possibly a bluetooth module. The microcontroller would receive the GPS data and extract the important information, speed and location, it would then make this available in a simpler form over a serial link. I may also include a bluetooth module which would transmit the raw GPS signal, this could then be used by other devices such as a phone or computer.

Speed Display

The speed display would be just that, a 7 segment led display which would receive the simplified speed signal and display it.

Tracking System

The final module is the tracking system, this would receive the location information and using an inbuilt gsm module relay the data to a server which would store the information. I have had an interest in location systems for a while and since a personal GPS tracker is impracticable because of power consumption issues I can at least track my car, it could even be useful if it gets stolen.

I tend to loose interest in projects quite quickly, especially the more in depth ones which is why I decided on the modular approach, even if I only complete two or one of the parts it is still a usable system.

Progress to date

GPS Test System

Over the past few days I have been playing around with an old bluetooth GPS and I have made a lot of progress on the first stage. The module I am using is quite old so internally it is fairly crude which is a bonus for me, it uses a prebuilt GPS module which is soldered to the main board so I have been able to tap into the GPS feed before it reaches the bluetooth module and divert it into a microcontroller.

Bluetooth module built into the GPS

I have now written a program which parses the data extracting all the information I would need and then outputting it over the bluetooth link, this is perfect for testing as I don’t need to have it physically connected to the PC.
None of these parts will be used in the final system, except maybe the bluetooth module if I can remove it from the circuit board, I am just using this setup for testing as I am currently waiting on a high performance GPS module to be delivered.

Locosys LS20031

I decided on a Locosys LS20031, this is a small unit with built in antenna, it seems to be fairly sensitive and has a fast update frequency of 5Hz.

I will post further information as the project progresses

Working on these projects alongside my PhD work and other existing personal projects has made me realize how much I enjoy the verity freelance work brings. Because of this I have decided to try and pursue more freelance type jobs, so if anything comes up in the future either web or electronics based I will take it, providing I have time for it that is.

I have also decided to update this blog and my main website, I will combine them into a single wordpress site with a uniform branding under my newly created logo.
I have fancied creating a logo for some time, I have no real use for one but I though it would be cool none the less.

ArthurGuy Logo

ArthurGuy Initials

This site and the other main one will probably be a bit messed up for a week or two as I find time to make the changes.

Kodak Zi6 Pocket Video Camera

For a while now I have been looking for something to record video, I was reluctant to go for a traditional camcorder as they are quite big, expensive and only do one thing. I had almost settled on one of the handheld video recording devices such as the Kodak Zi6, they can normally record HD video, there relatively cheap and portable.

The only thing putting me off was the overall quality, yes they can record HD video but the optics are cheap and you can see this in the videos they capture.

Ideally I would like the Canon EOS 5D digital SLR with HD video recording function I wrote about last year but that camera is over £2000 so it’s not going to happen. Today I came across the 500D and the fact it records HD video as well, I had no idea that any of Canon’s other cameras in this range recorded video.

Canon EOS 500D

The 500D is expensive but it is much more affordable than the 5D, for example Amazon currently have it for just under £600.

The real benefit of a video camera like this over the Kodak or a traditional video camera are the lenses. You can easily switch between different lenses for example a zoom or a wide angle, the zoom is also manual for grater accuracy.

I am fairly set on this camera now, my current SLR is the 300D and is now getting on a bit so this camera while still a little pricy is a good upgrade.