Boblight with Raspbmc – Ambilight Clone

When I first started seeing the Ambilight (Philips’s lighting system that allows the display to bleed out) clones popping up I knew I wanted to create one myself. The open-source system has been fairly well refined to this point, such that it is pretty much plug and play with Raspbmc (XBMC for the Raspberry Pi). ‘nadnerb’ has already created a tutorial for the process, which I followed, so I won’t go into the process here. This post is just to share my results.

Testing before install to avoid any aggravation!
Testing before install to avoid any aggravation!
I opted for some old trunking to hold the LEDs, held using hot glue. The trunking is stuck using double-sided duck tape.
I opted for some old trunking to hold the LEDs, held using hot glue. The trunking is stuck using double-sided duck tape.

AirPi: DIY Airplay Speakers using Shairport and a Raspberry Pi Updated

My last AirPi post has been popular – and still is – but part of why of like Arch linux is that it is constantly updating so you must be hands on, learning a new part of the OS the hard way!

Since my post a year ago, Shairport has some new features and dependencies, and Arch has moved to the systemd service manager, changing the tutorial process somewhat. In order to update it, I have run through the process with the current build (2013-02-11).

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Modelling a Double Pendulum in Simulink

One module I took during the final year of my degree was ‘System Modelling and Simulation’. A well taught and great module, one of the tasks was to model a double pendulum.

The approach involved deriving the equations of from the highest order of motion for each mass then working backwards through Simulink blocks to generate each term, which could then be to solve the equation – a bit of a chicken and egg problem! It was a an excellent task as the idea seems a little backwards at first and gave me a fresh approach to problem solving a model.

Below is the method extract from my report as the YouTube demo has generated some interest in the solution.

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Long-Range Coastal Autonomous Underwater Vehicle (AUV)

AUV with logo

The second semester of the third year of my Mechanical Engineering degree was a group design project. My group of six was tasked with the design of a coastal autonomous underwater vehicle (AUV). I was assigned design of the gliding sub-system (a long-range AUV it had to optimise energy use) and was also the business manager (as part of the project we were required to develop a business plan).

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Pressure Washer Pump Teardown (ProUser PP150 5.5hp 2200psi)

My ‘cross season has gradually gotten more serious, with two bikes and a pressure washer; both vital at last Sunday’s National Trophy. I’ve always wanted a pressure washer anyway (partly for washing bikes but also because I like mechanical things!) and this £100 GumTree special couldn’t be turned down. It’s been good to me so far but it’s clear the previous owner didn’t look after it. I noticed one of the pump mounting bolts had vibrated loose and after some suspicious drips, then loosing a bit of oil, I decided to take the thing apart to learn about it and give it a service.

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HDD Clock

With a cupboard full of old hard drives and some spare time, I recently set about making a persistence of vision clock. Using the platter of a hard disk, a slot is cut to allow backlighting to be emit. When the disk is spinning at 5400rpm+ and backlight constant, the disk appears opaque, as the slit is ‘refreshing’ each point of the revolution faster than our eyes. The trick is to measure the revolution time then flash or change the backlight colour at a fraction of this revolution time at the same point each revolution, in order to create a light segment. For example, flashing the light at a frequency twelve times the disk frequency in phase with the disk will create 12 light segments:

f_{light}=12.f_{disk}=\frac{12}{p_{disk}}

Expanding on this, one can create a light based clock, which takes some getting one’s head around on first sight!

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