Nikon DSLR D3100 - Mini Project?

I'm doing a project based on high speed photography. This requires us to manually adjust shutter speed, exposure time, focus and other things.
Now, the most important question: Can I trigger the camera using an external circuit, without dismantling the camera.

There are several remote releases available for the D3100.

Here's one of them.
http://www.amazon.com/...B003XN4XJU
And here's a sample of the range you can find.
http://www.amazon.com/...zon.com/s/

Here's also some I found on Ebay for you.
http://shop.ebay.com/i.html?rt=nc&LH_PrefLoc=1&_nkw=d3100%20remote%20shutter%20release&_dmpt=Camera_Camcorder_Remotes&_fln=1&_trksid=p3286.c0.m283

Hope this helps