Projector Power Party People
Thanks to an almighty team effort, we managed to power a projector, laptop and some sound with five pairs of legs. We also had a play with various sound systems, decks, electric keyboards, guitar amps and anything else we could get our hands on.
[youtube=http://www.youtube.com/watch?v=MLjDlpm4AUQ]
If you’re interested… We used both our ultra-capacitors, no lead-acid battery, our new inverter, only one pair of diodes and five 20amp fuses. Quite a basic set-up. We’ve yet to play with voltage regulators and other sexy things like that.
SEE THE KIT IN ACTION next Monday 2nd July, 8pm at The Portland Arms. Our first ever bike powered gig!
OPEN MEETING next Wednesday 4th July, 7pm at The Portland Arms. To discuss our long-term aims and ideas for the ‘grand cycle powered tour’ in 2008. All welcome.
15 Conversion Pins & 15 Motors
Tension Test
Yay! Our new inverter turned up the post and it looks like a beast. Bit of a weighty number but we’ve been recommended a Studer by Felix, who’s had one bumping around in his van for three months in Romania without a hitch. Lets hope ours fairs well on the road with the bike tour. In the end we went for the Studer AJ1000, which is rated at 800W continuous. That should give us enough if we decide to power the audio through AC, and at the same time not too ‘over the top’ if we run the audio direct from DC and just use the inverter for the projector. It’s also fairly small, very simple, supposed to be quiet and by the looks of things… rock hard.
George pops by the workshop and brings along a couple of friends, one of which is visiting from Edinburgh and volunteers for The Bike Station. He loves the idea of the project and you could see his eyes light up when we talk about the ’six month revolutionary crazy bike caravan tour’…
Then Lucy comes by and has managed to blag an expensive looking industrial digital newton force meter thing from work. Time to play around with the tensions we’re using to hold the skate wheel against the back tyre, to see if we’re getting slippage or wasting energy.
First off we discover that the ‘two bungee elastic things around motor and hooked on the frame’ method, that we’ve been using so far, is pulling the motor at around 95N. After a short brainstorm we manage to work out a way to test from slippage (which involved marker pens, bits of paper on wheels and counting rotations). We were happy that at 95N it wasn’t slipping. With some testing, it soon became fairly obvious that rider can feel when it slips, as long as they’re not ‘going for it’. We could lower the force a little without slipping, maybe to 85N or so, but didn’t seem to get any more power out of the system.
This was all very rough as we’re trying our best to keep a steady rate on the bike, therefore the volts level, and then try and gage output by looking at the amps. We really want to get geeky and have a setup that records all this information over time, probably via a laptop. If you know how to do this, via something like LabJack, do get in touch!
In the end, it was decided that pumped up tyres and enough force so it doesn’t slip - but not much more than that - will work just fine for us, for now. So back to out ‘two bungee elastic things around motor and hooked on the frame’ technique.
