UPDATE: Bretford is now offering a charging/syncing cart for iPad. Although they are the first one we've seen, we don't expect them to be the last company to do so. We'll update you when we learn more.
Using MacBook and 4 daisy-chained D-Link USB hubs (model # DUB-H7), we were able to successfully sync 20 (and possibly more, but we settled on 20 as our maximum as we didn't think we'd be able to do more than a normal iPod touch sync on our carts. We will be limiting it to 15, as we want to make it easier for teachers to be able to sync the "top row" and then the "bottom row" on our Bretford "Mobility" carts. We are using Bretford Mobility Carts, and modifying them to be able to sync and charge in the same cart. It's not completely pretty, and we're not sure MacGyver would approve (no duct tape used).
Below you can see our results of the sync tests.
Video media syncing:
|Number of iPads||Length of Video||Size of Video||Time needed|
|6||1 minute||23 mb||18 seconds|
|10||1 minute||23 mb||28 seconds|
|20||1 minute||23 mb||70 seconds|
|1 minute, 39 sec|
|Number of iPads||App name||Size of app||Time needed|
|20||iBooks||16 mb||49 seconds|
For what it's worth, here are pictures with some descriptions to go along.Overall view:
Sync cables are attached to the USB hubs, again attached via Velcro® to the top of the cart. They share the same hole in the back of the cart that the USB cable for charging goes through. They are very conveniently placed, and we fed multiple cables through them to keep the front of the cart (and inside the back) as neat as possible.
From inside the front, you can see the USB hub attached to the cart and the sync cables routed to the holes in the back. This hub is located on the left, hence its black USB cable routed out to the left side and on top of the cart for syncing. It's on the left because the USB ports on the MacBook are on the left...
Also, in the lower-left corner of the hub, you can see a USB cable from the other hub connected to the front daisy-chaining them so that we can sync the top row with 3 hubs.
Here are the other two hubs, the one on the left connected to the previously-pictured hub, and the one on the right connected to the middle one in the same way. The power cords are routed through the holes on the back of the top shelf, keeping them out of the way as they travel down to the power strip. There are several convenient routing options for cables in the Bretford Mobility cart.
Just a detail shot of the front of the hub, with 5 sync cables going into the holes below, and the one USB cable connecting to the other hubs.
Although not as pretty as we would like, you can see the sync cables sharing the same portal as the power cables. Two hubs are on the left (as you face the cart) and one on the right. The one on the right will be the one on the left as it comes out the top as in the next photo.
The cable coming out from the hub, with Velcro® attached to the side of the cart and the cable itself. We used the sticky-back kind, industrial strength (it has smaller/tighter loop and hook).
From the front of the cart, you can see the two cables that come out of each slot. We will zip-tie them together and we have put green electrical tape on the syncing cable in each slot (you can see that on the cable that is connected to the model iPad in the photo).
Bretford's cable management allows for two cables (built for one, obviously, but we can fit two) to keep them neat at the top of the slot.
Finally, in this photo, you can see the top row finished (from the back), and we will continue to do the same thing for the bottom row. When it's finished, we'll add another couple of photos here. Any suggestions for us would be most welcome as we hone our MacGyver skills.
We will deploy six of these to start, with possibly more soon. By the time we finish them, however, somebody may have already designed a charging/syncing cart...
And someone has: http://apple.bretford.com/products/powersynccartforipad
Here's a parts list for those of you trying to figure out how much of what parts you'll need:
|6||USB Hubs||D-Link||DUB-H7 7-PORT USB 2.0 HUB|
|2||Power strips||Any||Need vertical plugs, not horizontal|
|?||Sticky-sided velcro||Velcro||One side should stick to cart, other to back of hubs and such.|
|?||Zip ties||Any||As much as you need to keep cables "pretty"|
|1||6' extension cord||Any||Industrial strength, as it gets plugged in and unplugged a lot. We got an orange one to make it easy to see.|
|60||USB sync cables||Any||30 come with your iPads already, we had extras from our iPod carts, you can buy generic and another color would make it easy to distinguish power from sync.|
|1||Roll electrical tape||Any||We used as a way to distinguish power from sync, but if you buy other colored cables, then you don't need it.|