Did you ever get a chance to look at the retractable TV screens they 
have in airplanes? The idea is simple enough: two linkages with one 
pivot point. One end can be attached, in your case, to a hobby RC servo 
(you will need one with metal bearings if the hatch is a bit heavy) and 
the other is attached to a pivot on the hatch itself about midway 
between the hatch hinge and the edge that opens up. Of course you would 
use a hardware PWM with a PIC to open and close the hatch. Look for a 
hobby servo like Hitec and the package comes with little plastic 
linkages that you can use. If the hatch is heavy then you can find metal 
linkages on line at places like smallparts inc.
Good luck
Madhu


Matt Johnson wrote:
> I want to make a "access hatch" or panel that is flush mounted in the 
> ceiling of my living room. When I flip a switch, it will lower and their 
> will be a security camera exposed to monitor the room. To most of you I am 
> sure this is extremely simple as it is just a servo (not sure if 
> continuous drive or standard) driving some sort of worm gear going between 
> predetermined point A and point B.
> 
> My question is is this too simple of a project to involve the use of a 
> microcontroller? has anyone done something similar that I can see some 
> source code for? I wasnt sure if I can do the same type of thing just 
> using an IC circuit or not. I also am not sure what to use for the 
> mechanical components and hatch. I figured someone here has done a opening 
> hatch before. I just need some direction. Thanks.
> 
> - Matt Johnson
> 
> 
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