SpokePOV mounted in fan?

[pdp7]

Howdy,

I would appreciate any feedback or insight the community may have on this. I'd like to use the SpokePOV to create a display for a Maker Faire booth. Given the design of the booth, a bike isn't a good option. Thus, I'm looking at ways to have a SpokePOV rotate via electric power, and be safe enough for kids that may be visiting the booth.

The best idea I could think of so far would be to mount the SpokePOV inside a box or pedestal fan. I plan to order 3 boards, so I believe it would only need to go ~7mph. However, without trying, I'm not sure if the fan grill/cage will disrupt the image too much, or if I can place the magnet for the hall sensor appropriately. Additionally, I'm trying to think if there are any other safety aspects I'm overlooking.

Has anyone tired a similar approach?

Or any have an other ideas for making the SpokePOV into a booth display that doesn't require a bike?

Thanks!
Drew
http://twitter.com/pdp7

[pdp7]

Well, sometimes the answers are right under one's nose!

What did I spy at my hackerspace, Pumping Station: One, in Chicago at our weekly meeting last night? Nothing other than a blue SpokePOV kit mounted in a box fan lookin' all awesome!

http://pumpingstationone.org/2011/04/ps ... a-new-fan/

Our most excellent member, Crimson, decided to take the SpokePOV from one wheel of the our TRON lifecycle (made for the Scion Hackerspace Challenge - http://pumpingstationone.org/2010/10/psone-takes-on-the-machine/). He removed the fan blades since it was 5 bladed instead of 3 blades. Then he cut out of plywood a new 3 legged propeller and attached the 3 SpokePOV boards with zip ties. The magnet is affixed to the fan grill and the hall effect sensors detect it well.

I feel much better about the viability of my project now that I've seen Crimson's work! Just in time as I've got 12 blue SpokePOV boards arriving tomorrow

Cheers,
Drew
http://twitter.com/pdp7

[pdp7]

Here's a nice snapshot of it. It's very clear even through the grill:

http://twitpic.com/4rr1m5

[carmatic1]

interesting... the spokepov can keep up with the rpm of the fan?

[pdp7]

Yeah, I'm not the exact speed the fan is moving at, but there are 3 SpokePOV boards and it looks great. It was just some old fan in the space, Hawaiian Breeze.

I'm gonna be building the SpokePOVs I ordered later this week so I'll update with what fan I end up using. Ideally, I'd like to find a fan with 3 blades as the 5-blades had to be removed from the photographed box fan and a new 3 blade structure made from plywood.

Cheers,
Drew

[Crimson13]

Yeah to echo Drew's post, the povs seem to be able to keep up with the fan without much of an issue. I guess if you wanted to have more speed control than the fan settings, you could use a light dimmer switch instead of the fan settings. That way you could dial in the speed you need/want.

Once I'm able to get some measurements off of the povs at the space I'm going to make a sketchup file of a 3-bladed pov mount for others to use in fans. And once I find a CAD program I like, I'll do it in more of a 2D format as well. I have most of this done, since I made a template for me to use on the scrollsaw to make the plywood frame that the current fan is using. The only thing is that I didn't add the "fingers" that hold the pov. One short finger goes in-between the leds and the bottom battery, up to the second battery. The long finger runs the length of the pov.

[pdp7]

Great stuff, Crimson! I look forward to fabricating the design at the MSI FabLab tour on Saturday http://pumpingstationone.org/2011/04/psone-behind-the-scenes-at-msis-fab-lab/