House Access Help

I'm rather new at home automation. I'd be interested in feedback regarding a plan for a passive entry system to my home. The plan and components I have envisioned exist but I have not seen them configured in the way I've planned.

Pictures from the top, inside, and outside of my front door can be found at the following urls (I apologize in advance for the smallness of the jpg's that msn groups pulled from my computer -- hopefully my description below will provide the detail that may be so small as to be illegible on the jpgs):

Top View

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Outside View
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Inside View
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Principle elements of the plan: (1) Long range proximity reader - It seems as if the normal distance for a proximity reader is something on the order of 6" or less. My intention is to be able to approach my front door and have it open as I approach without having to remove my key card from my wallet. This would suggest a range quite a bit longer than 6". Long range proximity readers are out there (HID Maxiprox) but it appears they are targeted to parking garages and such.

Would anyone like to comment on applying a long range proximity reader to home automation application?

Since the long range proximity readers I've come across are on the order of 12" x 12" or larger my thought is to mount it indoors (in the drywall??) where it is not an eyesore. Should I reasonably expect this sort of installation to work? Are there challenges with this sort of installation that I need to be aware of?

With a long range proximity reader I need to be concerned with the distance that the reader penetrates indoors (I have provided for this in my diagram by specifying that the read area extends only outside the front door). I don't want to be activating my front door once I'm inside. Are proximity readers typically directional? Can they be made directional by the use of properly placed shielding? (metal??)

(2) Keypad mounted outside - I've seen some keypads (some elegant, some ugly) on the web (feel free to make suggestions if you would). They keypad would provide access in lieu of a keycard (for house cleaners, guests, etc.) allowing me to add/remove access codes and limit access to specific times.

(3) Control unit mounted inside - Don't know if this is the proper term but I understand that separating this from the keypad is a more secure solution.

(4) Electric strike - Would be activated by either proximity reader or keypad via control unit. I like the fact that the electric strike is mounted in the door frame and is therefore capable of being powered without having to wire the door itself.

My expectation is that the strike, when activated, would allow the door to swing open for some preset time. I'm wondering about how much time I should alot. I suspect it's easier with a short range proximity reader as one expects that entering the door is immediate upon activation. I don't want the door to prematurely "lock" so it should be longer than 1 second delay. On the other hand, I don't want the door to swing open for 10s of seconds after entry so the delay should be shorter than 30 seconds. Is this going to be a pain in the butt?

(5) RF electric deadbolt - I would love to have a deadbolt which functions in the same way as the electric strike. Since a deadbolt isn't a latch and since a deadbolt isn't spring activated it appears an electric strike won't work with a deadbolt. That leaves an RF deadbolt with a key fob as an additional component to the plan. The idea of replacing batteries for the thing seems rather inelegant to me. My father-in-law suggested a second latch acting as a deadbolt (with a second electric strike), IF there exist latches which act (and look -- who wants two doorknobs on a door) like deadbolts. Does this beast exist? Would this be as secure as a deadbolt?

(6) Fail secure - Both the deadbolt and the electric strike would be fail secure. I would have both keyed on the outside and a handle/knob on the inside in case of power failure.

Please feel free to comment on any or all parts of the plan. What am I overlooking or failing to appreciate? What should be I looking for from these components if I was interested in hooking this into a comprehensive home automation system?

Thanks for your patience in reading this rather long post.

= Joseph

Reply to
joseph_stiehm
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[ snip]

There is a turn-key, long range RFID using Wavetrend hardware

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developed and market for home automation by iAutomate that does what you are looking for. Interface software is available for Crestron and Homeseer home automation systems.

The principal drawback is price, especially if you want more than one location (reader). Cost for a minimal setup is about US$700.

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Homeseer RFID discussion board is here:

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As with many Homeseer plugins, there are "issues".

I've looked for less expensive options, including home-brew DIY and found none. Eventually they will emerge. Wavetrend (what iAutomate uses) themselves have less expensive readers. Keep us posted on what you learn.

HTH ... Marc Marc_F_Hult

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Reply to
Marc_F_Hult

Marc,

Thanks a lot for the info. I was reading up this past weekend. The iAutomate solution is interesting. A couple of questions if you don't mind answering them:

1) The iAutomate (Wavetrend) solution involves tags that are battery operated and have a lifespan of 5 years. Are you aware of any good long-range proximity reader solutions which involves strictly passive tags that don't require their own power source (HID seems to fit the bill, but it doesn't seem to be marketed to home automation)?

2) The setup I have envisioned has the reader installed in the house with the read envelope extending outside the house. All the readers I've looked at seems to be omni-directional. Any ideas on creating a hemi-spherical area of activation (on the outside of my house only)? I looked at the front door this weekend with a tape measure. In order to create a passive, transparent solution to opening the door I figured a radius of 36" around the doorknob (at wallet level) would be ideal. I don't want to trip the front door reader from the inside so I figured I needed to do one of 4 things: a - Shield the reader (using metal?) so it only detects tags from one direction. Is this realistic? b - Set up the reader outside (ugly for a number of reasons) so that the envelope doesn't penetrate to the inside of the house c - Use a reader and a second, fixed-location, tag set up asymmetrically and measure distance of the 1st tag against the distance to the second tag to determine whether the door should open (I don't even know if this is feasible) d - Get two readers (expensive) and set them up in conjunction to create a crescent of activation (tricky?)

Again, I'm new to this so maybe my concern is due to naivete on my part (it may be that this is something HA folks simply "deal with"), but before I look to spend $700 on the venture I'd like to establish the feasibility of my concept.

Thanks for your time.

= Joseph

Reply to
joseph_stiehm

Joseph,

Sophisticated (expensive) systems with multiple sensors can locate an RFID tag to within centimeters in 3-D space in real time. This in turn can be used to calculate diretion and rate of movement (velocity vectors) which would be very useful to address a goal that I've played with off-and on for years.

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This site has some very useful info:

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Earlier this year, I wrote in ccomp.home.automation about G2 Microsystem's

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new active RFID chip.

' The $12 (in quantity; scheduled to ship 3rd quarter 2006) G2501 chip performs active RFID over standard 802.11b WIFI. Battery life using two AA's is projected at 5 years.

The chip is programmed through a url and "uses existing WIFI wireless access points on the network, meaning no new network installation is required" if a WIFI network exists.

Spatial location of the tag to within 15 feet can be accomplished by triangulation using three WIFI access points, or to within about six feet using ISO 24370/ANSI 371.1 Time Delay of Arrival (TDOA).

The chip also has two standard passive RFD technologies built in: Electronic Product Code (EPC) and a standard 125mhz magnetic. These are powered internally, don't need the WIFI transceiver to turn on and "can talk to other existing RFD systems in their neighborhood".

GPIO, UART, SPI, current loop and ADC interfaces are built-in and on-chip. The latter are specifically designed for sensor interfaces such as temperature, humidity, light, radiation and so on. '

With respect to the battery issue, I'd work under the assumption that five years (cited battery life) is a long time in the rapidly evolving long-range RFID arena. It would be nice to see a device the size and thickness of a credit card including battery that could be kept in a wallet. With that form factor, the battery life would not be an issue (for me.) Credit cards all expire in less than five years, so why shouldn't RFID tags?

There are of course passive RFID tags, but their range is limited. The G2501 chip discussed above can employ both techniques.

HTH ... Marc Marc_F_Hult

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Reply to
Marc_F_Hult

See my other post in this thread.

Can't see why not (but I have no hands-on experience). One conventional approach is to triangulate using multiple readers. The G2 chip solution using WIFI I cite in my other post in this thread would serve to keep the 'reader' costs way down and so allow for triangulation at moderate cost (software permitting).

I don't think I understand this.

Yes. This is a 2-sensor (1-D) version of what I meant by triangulation (2-D localization).

Three points form a triangle.

So would I ;-)

... Marc Marc_F_Hult

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Reply to
Marc_F_Hult

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