Aside from writing Websites, here at TCK, we love to build real world objects.
As you can see from the ‘Advertising Systems’ page, we build ‘proper’ electronics…
The LEAF Electric Bike Project
Other, equally exciting and fun projects include the ‘Electric Bike’ for LEAF Sheffield.
A couple of years ago, one of LEAF’s volunteers suggested that they needed lights to work under as the nights drew in past autumn. As there is no mains power supply at LEAF, this presented quite a ‘challenge‘. (We prefer the work ‘challenge’ to the word ‘problem’. So much more positive.)
Another volunteer had seen a demonstration on TV that showed a guy riding a stationary bicycle and generating power to light lights.
“Simple!” someone shouted.
Yes, in fact it is fairly simple to hook up a generator to a stationary bicycle -as long as you have a ‘bike trainer’ available for indoor, stationary cycling. All you do is hook up a DC motor connected to the back wheel, and sure enough, the motor acts as a generator when turned. Simple high school physics.
BUT, (…and this is a fairly HUGE ‘but’…), as soon as you stop pedaling, the lights go out.
You need some way of storing the electricity after you’ve generated it.
“Simple!” someone else shouted. “Hook it up to a car battery!”
Ah. Stop right there. Yes, it may sound a simple proposition, but in actual fact, it’s not simple at all!
If you merely connect a car battery to a generator, you will very quickly discover that a generator is actually a motor in reverse. Unless you can cycle really, really quickly, you’re just going to eventually flatten the battery still further.
What is needed is a method of controlling the power generated by the motor, then presenting it in a form that the battery will ‘see’ as charge.
It has taken many months of work, but we do now have a system that convert a cyclist’s pedaling into electricity, but more than that, any excess power not used for immediate lighting can now be safely stored in a marine or leisure battery for later use.
This system, aside from being used by LEAF is also being used by Trade Base, a project similar to LEAF, again with no mains electricity supply.
We’ll be popping some accompanying photos up here soon…
Movie Poster Display Board
One of our staff has a real passion for original movie posters, particularly after we did the Movie Poster Company website a couple of years ago.
“Wouldn’t it be great,” he said “If there was a way of displaying movie posters, but with backlighting, so you could turn the room’s lighting down, and still be able to see your favourite poster?”
Yes, it would be great, and yes, it is great.
We are currently building a large (31″ x 41″) ‘light board’ that you can clip a movie poster into, then press a button, and it will light up -back lit.
Obviously, the real trickery comes in to allow the user to set their own brightness levels via two pushbuttons.
Of course, the board will remember this setting when switched off.
The electronics and programming is pretty simple -merely a very small PIC processor controlling a PWM (Pulse Wdith Modulated) output for the brightness levels. The desired brightness is then stored in non-volatile memory, so it won’t ‘forget’ the level when it is switcthed off.
Pictures to soon follow!