Motion sensors might be the ticket.  For example,

----- Original Message -----
From: "Andreas Orphanides" <[log in to unmask]>
To: [log in to unmask]
Sent: Thursday, August 15, 2013 11:12:02 AM
Subject: Re: [CODE4LIB] Way to record usage of tables/rooms/chairs in Library

Oh, that's a much better idea than light sensors. One challenge with that
might be difficulty in determining what "vacant" looks like
authoritatively, especially if people move chairs, walk through room, etc.
But much more accessible than actually bolting stuff to the table, I would

On Thu, Aug 15, 2013 at 1:03 PM, Schwartz, Raymond <[log in to unmask]>wrote:

> Hey Dre, Perhaps a video camera with some OpenCV?
> -----Original Message-----
> From: Code for Libraries [mailto:[log in to unmask]] On Behalf Of
> Andreas Orphanides
> Sent: Thursday, August 15, 2013 8:55 AM
> To: [log in to unmask]
> Subject: Re: [CODE4LIB] Way to record usage of tables/rooms/chairs in
> Library
> If I were feeling really ambitious -- and fair warning, I'm a big believer
> that any solution worth engineering is worth over-engineering -- I'd come
> up with something involving light sensors (a la a gate counter) mounted on
> the table legs, just above seat height. Throw in some something something
> Arduino or Raspberry Pi, and Bob's your uncle.
> I find myself more intimidated by the practicality of maintaining such a
> system (batteries, cord management etc) than about the practicality of this
> implementation, actually.
> -dre.
> On Wed, Aug 14, 2013 at 7:59 PM, Thomas Misilo <[log in to unmask]> wrote:
> > Hi,
> >
> > I was wondering if anyone has been asked before to come up with a way
> > to record usage of tables.
> >
> > The ideal solution would be a web app, that we can create floor plans
> > with where all the tables/chairs are and select the "reporting time",
> > say 9PM at night. Go around the library and select all the
> > seats/tables/rooms that are currently being used/occupied for
> statistical data.
> >
> > We would be wanting to go around probably multiple times a day.
> >
> > The current solution I have seen is a pen and paper task, and then
> > someone will have to manually put the data into a spreadsheet for
> analysis.
> >
> > Thanks!
> >
> > Tom
> >