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eben
03-02-2008, 06:00 PM
I want to build an automatic watergun to keep the cats off the counter even when we're gone or asleep. My plan is to fit the cats with reflective collars, and then use a webcam to hose down bright moving things. Obviously it'll have to have some sort of light near the camera for that to work, and it's probably easiest if the camera is attached to the barrel. So I need to run a motor (or valve on a pressurized container), and a servo (two if I get fancy). The computer is easy to get. I can get the motor, tubing, and nozzle by gutting a battery-powered watergun. (There's got to be a cheaper / less wasteful way, however.) They probably have appropriate servo(s) and controllers here. See anything I've forgotten? Thanks.

Matt
03-02-2008, 07:35 PM
This sounds like a fun/funny project. But I was thinking that there must be far cleaner ways to accomplish your goal. Such as sounds cats don't like or something that rattles maybe. I would want to avoid spraying water all over my kitchen at all costs, but that's me.

Lets see, maybe you can capture a feed from an infrared security camera and use roborealm as a trigger. Or you might be able to use an array of simple IR range sensors as invisible trip lines. Phidgets has an analog motion sensor also.

You will probably need to set up some kind of webcam to capture footage for research to see what works and what doesn't. If you figure it out be sure to let us know. I have a good friend who has cat rage* that needs your device.


* cat rage: similar to road rage where a friend during phone calls breaks the conversation to scream nonsense in your ear. IE: "So I was talking to Brian and... HEY! YOU SEE ME TRYING TO MERGE PAL!!! MOVE OVER... Anyway I was talking to Brian." or, the cat version "Are you going to the party on frida... GET OFF THE BOOKSHELF MUFFIN!! I SWEAR TO GOD!! Yeah, friday, are you going?"

eben
03-02-2008, 11:20 PM
But I was thinking that there must be far cleaner ways to accomplish your goal. Such as sounds cats don't like or something that rattles maybe.Well, one cat's deaf, so sound's out. Maybe a projectile that isn't harmful but is annoying (like http://www.thinkgeek.com/interests/usb/8a0f/ but witth more than 4 shots)?


I would want to avoid spraying water all over my kitchen at all costs, but that's me.As long as I land the shot, it doesn't matter. *evil grin*


Lets see, maybe you can capture a feed from an infrared security cameraWould that need an IR LED? Not that that's a big deal...


Or you might be able to use an array of simple IR range sensors as invisible trip lines.Yeah, I'd hate to sic it on a human. It's supposed to be OK for us to use the counter.

Matt
03-03-2008, 12:07 PM
What I had in mind was a USB based night vision security camera like this (http://www.gainsaver.com/bNetStore/Templates/Site/Template1_BCA/TplDefault.aspx?TCode=53&FCode=15&Param1=3&Param2=0&Param3=All&Param9=1&Param10=12246).

>>>Yeah, I'd hate to sic it on a human. It's supposed to be OK for us to use the counter.

I was assuming that there would be an on off switch somewhere to save the humans :p

What about an Air in a Can (http://www.uline.com/Browse_Listing_6955.asp?pricode=wk622) blaster device? That should probably freak out a cat. (even deaf ones) You could maybe buy one of the IR sensor kits (http://www.trossenrobotics.com/store/c/3157-IR.aspx) and use that to place 4 or 8 triplines around the counters and tie each one to an air can that covers that area. A simple program could record each trip event with time and that security camera I found actually records only when there is motion I think so that could run completely independently capturing the evidence ;)

Can anyone else think of stuff that would create a poof of air that may be easier than and air can with a servo? An empty paintball gun comes to mind, but that's a little extreme. (Plus people are trying to sleep) Maybe a CO2 powered pellet gun? Something that can be powered by a relay would be ideal.

MinyFly92
03-03-2008, 02:33 PM
* cat rage: similar to road rage where a friend during phone calls breaks the conversation to scream nonsense in your ear. IE: "So I was talking to Brian and... HEY! YOU SEE ME TRYING TO MERGE PAL!!! MOVE OVER... Anyway I was talking to Brian." or, the cat version "Are you going to the party on frida... GET OFF THE BOOKSHELF MUFFIN!! I SWEAR TO GOD!! Yeah, friday, are you going?"

Thats really funny. And why thats really funny is because my mom does that.

Anyway I was just thinking wouldnt you get shot a lot for holding a spoon, fork, knife, ect. It seems like there are too many shiny things in a kitchen. But otherwise nice concept.

Matt
03-03-2008, 03:28 PM
Would that need an IR LED? Not that that's a big deal...


Okay, I finally got what you meant by that, an LED on the cat. For all my ideas I was thinking of a system that is disarmed when humans are around. I think trying to specifically identify cat verse human would be too difficult. If you just manual turned the system on every time you left for awhile and did this for a month I'm thinking that would make the cats quit forever. Sort of Pavlov's dogs training.

Alex
03-03-2008, 04:42 PM
I think trying to specifically identify cat verse human would be too difficult.

I think RoboRealm can do this.... Tyberius?

DresnerRobotics
03-03-2008, 04:52 PM
I think RoboRealm can do this.... Tyberius?

No, probably not. Not strictly between humans and cats. Neither have defining characteristics that are distinguishable by roborealm. Easier to give the cats a certain color collar, and have roborealm identify that.

eben
03-03-2008, 11:13 PM
> Would that need an IR LED? Not that that's a big deal...

Okay, I finally got what you meant by that, an LED on the cat. Actually, I was thinking illumination for an IR camera. I have some amulets (? dunno if that's the right word; acorn-size thingies that hang from the collar) that originally came with a cat door; they flash IR every few seconds.

So theoretically I don't need any extra light: if it happens to be too dark and the camera sees _anything_, it's a cat.

Adrenalynn
05-14-2008, 04:06 PM
I can't resist this thread, even if it's old...

Preferred method:

3v glow plug
small copper tube
small ball of flash cotton
small wad of flash paper

I could build that to track the cats from just a stand-alone make controller, a PIR motion sensor, and use the motor drivers on the make controller to fire the glow-plug.

Here, Kitty Kitty! PHOOOOSH. Singed kitty.

The big downside is that burned hair smell...

So we move on (assuming we don't want to talk about building carbon-arc furnaces for a more permanent fix...):

You're looking for a QEV - Quick Exhaust Valve.

Dirt simple - an air resevoir, a QEV (in this case, either a 3/4" or 1" irrigation valve), and a bunch of PVC.

You'd need to make a PVC piston, but that's pretty simple too.

The QEV would be fired with a relay from a servo controller or with a motor controller.

With simple tools, this is a ~3hr project. Let me know if you want me to do a walkthrough.

PM if you want to know how to add lighter fluid and an igniter... :P

metaform3d
05-14-2008, 07:51 PM
Neat idea.

My idea for detection would be a camera pointing down at the counter directly from above. You should be able to convert motion-detection (temporal image difference) to a blob. Only blobs of the right cat-size would trigger the weapon. The blob would also give you the place to aim (CG for XY, Z assumed to be cat-height above counter).

If you could make an exception for moving blobs that have part of their extent crossing the edge of the counter (like an arm holding a salad bowl, for example) then you wouldn't need a cutoff for humans. Only shoot at cat-sized blobs surrounded by stable background.

Don't know if roborealm can do it -- I've only played with it a little -- but it sounds right up the right alley.

metaform3d
05-14-2008, 07:53 PM
3v glow plug
small copper tube
small ball of flash cotton
small wad of flash paper
Don't know if I'd want an autonomous flame-wielding robot running loose in my kitchen. Never know what might catch fire. (Although that was an awesome instructable.)

Adrenalynn
05-15-2008, 12:07 AM
What better place than your kitchen?

It bakes, it fries, it flambes, and it keeps the dam'd cats off the counter.

I have a fool-proof cat detector/eliminator. Even in hibernation mode it can detect a cat several hundred feet away, instantaneously come out of power-save and into full operation, and run the cat down at 30+ mph.

http://www.sonotthedrama.net/thor/thor-grass-look-side.jpg

http://www.jlrdesigns.com/thor-chew-cat.jpg

Matt
10-18-2008, 07:11 PM
LOL, here is a cheap solution that is hilarious

http://www.plasma2002.com/blenderdefender/