Difference between revisions of "Home Automation"

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(Servo Controlled)
m (Edits to Flowchart: typo)
 
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=Road Map=
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=Roadmap=
 
* Pick an authentication method '''DONE''' USB
 
* Pick an authentication method '''DONE''' USB
* Computer driven scripts to send signal to USB
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* Computer driven scripts to send signal to USB '''DONE'''
 
** read in USB info '''DONE'''
 
** read in USB info '''DONE'''
** send out serial command
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** send out serial command '''DONE'''
* Pick an physical entry method
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* Pick an physical entry method '''DONE'''
* Use serial command to trigger entry method
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* Use serial command to trigger entry method '''DONE'''
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* Attach everything to the door '''DONE'''
  
 
=Entry Automation=
 
=Entry Automation=
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===Cons===
 
===Cons===
 
* Keys easily stolen with anonymity
 
* Keys easily stolen with anonymity
* Your tracking me!
 
  
 
===Implementation===
 
===Implementation===
 
====Materials====
 
====Materials====
* Need a reader with good range. Can be found for [http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=300060435830&ssPageName=MERC_VI_RSCC_Pr12_PcY_BIN_Stores_IT&refitem=300222598671&itemcount=12&refwidgetloc=active_view_item&usedrule1=StoreCatToStoreCat&refwidgettype=cross_promot_widget&_trksid=p284.m184&_trkparms=algo%3DDR%26its%3DS%252BI%252BSS%26itu%3DISS%252BUCI%252BSI%26otn%3D12 under $100]
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* Need a reader. Can be found for [http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=300060435830&ssPageName=MERC_VI_RSCC_Pr12_PcY_BIN_Stores_IT&refitem=300222598671&itemcount=12&refwidgetloc=active_view_item&usedrule1=StoreCatToStoreCat&refwidgettype=cross_promot_widget&_trksid=p284.m184&_trkparms=algo%3DDR%26its%3DS%252BI%252BSS%26itu%3DISS%252BUCI%252BSI%26otn%3D12 under $100]
* To build a system that can perform coming/going detection, would need two readers. or 1 + N readers, where N is the number of approachable directions
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* Need tags
* Need a writer.  [http://search.ebay.com/search/search.dll?sofocus=so&sbrftog=1&dfsp=32&from=R40&satitle=RFID+writer&sacat=-1%26catref%3DC6&sargn=-1%26saslc%3D2&sadis=200&fpos=ZIP%2FPostal&sabfmts=1&saobfmts=insif&ftrt=1&ftrv=1&price=1&saprclo=&saprchi=100&fsop=32%26fsoo%3D2 Under $100]
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** Some writers are substantially more expensive.  Q:  Why the price difference? 
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* Need a server
 
* Need a server
  
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===Pros===
 
===Pros===
 
* Rotating keys are available
 
* Rotating keys are available
* Someone must have physical access to the fob to capture the non-rotating key
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* Physical access is required for key duplication
 
===Cons===
 
===Cons===
 
* Hands-on access
 
* Hands-on access
* 1 wire interface may be fakable with any interface that has the same signal levels (very cheap and easy buttonforging)
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* Interface may be fakable with any interface that has the same signal levels [[iButton Spoofing]] --[[User:Omegix|Omegix]] 23:02, 8 May 2008 (CDT)
** ''prove it'' --[[User:Strages|strages]] 20:18, 8 May 2008 (CDT)
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** Unimportant, because the threat of theft through kicking the door in is much higher than spoofing --[[User:Korc|Korc]] 20:51, 8 May 2008 (CDT)
*** [[iButton Spoofing]].  I'm not promising to get around to this anytime soon, but I'll layout how to spoof the static key iButton here. [[User:Omegix|Omegix]] 23:02, 8 May 2008 (CDT)
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** ''It doesn't matter.  Old keys are still eliminated from the system.  And the threat of theft through kicking the door in is much higher than copying a valid key.'' --[[User:Korc|Korc]] 20:51, 8 May 2008 (CDT)
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* User may forget to log their entry to the area.
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** If door is open, no incentive to use key
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** Group of people walk in at once
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** Someone knocks and has the door opened for them
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** ''All these Cons are valid for any system'' --[[User:Korc|Korc]] 19:26, 8 May 2008 (CDT)
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*** <i>True, but not so much with RFID.  With RFID as long as the person has their tag on them, simply walking within a few feet of the reader will activate it.  Most people are used to RFID readers with short reading distances, ones with longer throws are found at storage units so that people don't have to get out of their cars.  There's a cheap long throw reader on ebay that can do 40 meters.  Of course, if people don't keep their RFID tag/card on their person, then that screws the pooch. </i>[[User:Omegix|Omegix]] 23:07, 8 May 2008 (CDT)
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*** <i> This point makes no sense!  Why do we need a long range reader?  Why do we need to track people once they are at the shop?  If you have a long range reader, won't this make it harder to track coming and going of people?  The hole purpose of access control is to first control access to "users" and second keep track of people coming and going.  Getting a long range reader so you can be lazy and not have to hold up your card is rather stupid, because now if I even get close to the reader, its tagged me as coming or going.  Unless of course you just track everyone in the vicinity, but I'm guessing that will be harder to do, cost more...and frankly I don't want you to track me with RFID.  With the iButton you simple touch it to a pad, stating you have either entered or exited for the day.  If you don't, you won't get credit for being there...seems simple enough to me</i>--[[User:Jim Shoe|JimShoe]] 10:24, 9 May 2008 (CDT)
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==USB Authentication==
 
==USB Authentication==
 
===Pros===
 
===Pros===
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to not only receive a signal from the computer, but also sense a window-open detector, and control a servo.  
 
to not only receive a signal from the computer, but also sense a window-open detector, and control a servo.  
  
This sketch from Feltinix shows how a stick hanging from the servo could be used to manually unlock the door in event of a power failure:
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This sketch from Feltinix shows how a stick hanging from the servo casing could be used to action / reaction hold the servo in place.
 +
 
 +
If you were to attach the stick to the deadbolt turner or the plastic connected to the servo motor shaft, that would allow for a manual unlocker for the door in the event of a power failure
  
 
[[Image:Tanstaafl%27slockproposal.png|thumb|none|100px|10/04/2008]]
 
[[Image:Tanstaafl%27slockproposal.png|thumb|none|100px|10/04/2008]]
  
 +
This image from gregabyte shows a mechanical override system that could be implemented for under $20
  
The flowchart for the circuit is below.
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[[Image:Img-X08155151-0001.jpg|thumb|none|100px|10/04/2008]]
 +
 
 +
 
 +
The flowchart for the circuit is below.
  
 
[[Image:ServoControlled.jpg|thumb|none|100px|10/04/2008]]
 
[[Image:ServoControlled.jpg|thumb|none|100px|10/04/2008]]
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=====Edits to Flowchart=====
 
=====Edits to Flowchart=====
 
# Sound a buzzer right before the door unlocks or locks so that users are aware that something is about to happen
 
# Sound a buzzer right before the door unlocks or locks so that users are aware that something is about to happen
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 +
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[[Category:Arduino]]

Latest revision as of 15:37, 4 March 2010

Roadmap

  • Pick an authentication method DONE USB
  • Computer driven scripts to send signal to USB DONE
    • read in USB info DONE
    • send out serial command DONE
  • Pick an physical entry method DONE
  • Use serial command to trigger entry method DONE
  • Attach everything to the door DONE

Entry Automation

General Implementation Notes

  • The system needs to be powered, and preferably include a UPS
  • Overriding key access is nice for graceful failure
    • Of course, this just underlines the fact that this is an access registry system more than anything
  • Probably need a normal handle in the door with an electric door strike for the cheapest implementation.
  • If the implementation simply replaces the metal key with a token, it will have the same problems. Unless two- or three-factor authentication is used and/or the physical security of the lock and door are improved, it's about as secure as it was.
  • Simple enough to manage the coming and going of people.

RFID

Pros

  • Hands-off access
  • Hands-off tracking of access
    • As long as user has their RFID tag on them, their presence within a certain proximity around the reader will be recorded.

Cons

  • Keys easily stolen with anonymity

Implementation

Materials

  • Need a reader. Can be found for under $100
  • Need tags
  • Need a server

iButton

Pros

  • Rotating keys are available
  • Physical access is required for key duplication

Cons

  • Hands-on access
  • Interface may be fakable with any interface that has the same signal levels iButton Spoofing --Omegix 23:02, 8 May 2008 (CDT)
    • Unimportant, because the threat of theft through kicking the door in is much higher than spoofing --Korc 20:51, 8 May 2008 (CDT)

USB Authentication

Pros

Each USB device has a unique serial ID. USB keys are cheap, readily available, and many can fit on a standard metal keyring.

Cons

Implementation

Authentication Flow

  1. User inserts key into USB hub hooked to a PC
  2. Computer reads serial ID of key
  3. Computer compares serial ID to list of valid serial ID in a table \ DB \ Flat File
  4. If good, computer writes data ("Unlock!") to USB line of Microcontroller
  5. Microcontroller throws a pin high for 5-10 seconds.
  6. Pin is likely 3-5volts. Pin is wired to either a 200ma transistor or relay
  7. Relay, when thrown, sends 12V of 200mA current to an electric doorstrike

Useful Microcontroller (Arduino/Freeduino) Resources

Suggested Implementation Phases

  1. Get microcontroller to throw a pin high
  2. Get microntroller to read commands issued from external system (serial/USB)
  3. Get microcontroller to throw Pin high after recieving external command
  4. Build and test simple door strike circuit

Circuit

In order to get 12V of 200mA current to the doorstrike, we'll need to protect the freeduino from flyback current. After consulting with protomech, 1kOhm resistor, one 1N4002 diode, and one 2N2222 transistor should do the trick for making a safe 12V relay for the doorstrike.

Other Materials

Mechanical Implementation

DoorStrike

Electric Deadbolt

  • This Guide Shows how to easily hack a Powerbolt 1000.
    • Cost is roughly $80

Servo Controlled

The idea here is to have a servo attached to a standard deadbolt. The microcontroller will need to not only receive a signal from the computer, but also sense a window-open detector, and control a servo.

This sketch from Feltinix shows how a stick hanging from the servo casing could be used to action / reaction hold the servo in place.

If you were to attach the stick to the deadbolt turner or the plastic connected to the servo motor shaft, that would allow for a manual unlocker for the door in the event of a power failure

10/04/2008

This image from gregabyte shows a mechanical override system that could be implemented for under $20

10/04/2008


The flowchart for the circuit is below.

10/04/2008
Edits to Flowchart
  1. Sound a buzzer right before the door unlocks or locks so that users are aware that something is about to happen