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Cart Locking System Released as Open Source
An anonymous reader writes "You may have noticed that over the past few years it has become increasingly common to find supermarket and large retail store shopping carts equipped with 'boots' designed to lock up if you try to take the cart outside of the store. Now, someone has discovered through some clever analysis the signal used to both lock and unlock carts, and has designed a portable system that locks up all carts within 20 feet of the emitter! They have released the schematics, software, and detailed instructions for assembling the systems on Instructables, an online magazine dedicated to releasing howto's for everything from rat taxidermy to Shopping Cart EMPs under a Creative Commons License."
a fair amount of mischief about.....or maybe it's just cowboyneal.
We came,we saw, we kicked it's ass!
... like a lot more fun than an iPhone. Plus it doesn't require a 2 year AT&T commitment ;-)
Is it really a good idea to show all pranksters in the world how to lock up a bunch of innocent people's carts in a store?
I'd much prefer if supermarket pranksters stuck to less annoying pranks, like hiding a speakerphone and ketchup bags in a baby-less baby-holder, having it play "crying" sounds, and then publicly "beating" the "baby" until it "bleeds".
Apology to Ubuntu forum.
will be of great interest to a certain inhabitant of the Sunnyvale trailer park.
the good ground has been paved over by suicidal maniacs
As if millions of homeless suddenly cried out in terror and were suddenly silenced. ;-)
Creative Commons is not Open Source. Creative Commons is not Open Source. Creative Commons is not Open Source.
That gets people to take it back to a cart corral instead of just dropping it in the parking lot... I think this is more aimed at people who try to steal carts (they're surprisingly expensive).
This 4th of July when both me & my neighbor get our lazy asses to the grocery store to get cookout supplies at the last minute, I will laugh evily when he flies over the handlebars & lands in his basket when we're both 10 feet away from the last case of beer.
Wanna fight ? Bend over, stick your head up your ass, and fight for air.
Fun with supermarkets and security strips:
1. If you're in the UK and you've bought region 1 DVDs, look inside the case and you'll most likely find one of those long thin security tags.
2. Peel off one of those security tags and stick it the underside of a shopping trolley.
3. Sit back and wait for some unsuspecting shopper to trigger the alarm, when going in nobody will really bat an eyelid, but if they walk out with a trolley load of shopping and it goes off, things will get interesting.
4. Tag as many shopping trolleys as you can for maximum fun.
5. ????
6. Profit!
Reminds me somewhat of this quote from bash.org- cag URL tara: When I was in high school, the school board decided that the biology students had to pay for the fetal pigs that were being dissected. After the course was done, my friend Amy demanded that she be allowed to take the pig, since she had paid for it. There was some WTF from the school, but she got her pig. That weekend, she and her brother dressed the pig up in some baby clothes and a blanket, drove down the street and lit a smoke bomb in the car. They were passing a couple walking down the street when Amy leaned out of the car and yelled "Save my baby" and tossed the pig at the couple. They were doing about 50 mph so she missed the couple. The baby/pig hit the sidewalk, skidded along the concrete, shedding parts and limbs before it impacted a mailbox.
She said she had never seen such a horrified look in her life. I mean, yeah, it's funny, and I hate to say that I laughed at it a lot (and still keep doing so whenever I read it), but at the same time I'm thinking that they should have been locked up for doing something that would have been quite the opposite of funny- if not downright traumatic- for the pedestrians.
1. nerdy does not imply not-asshole
2. this was not actually designed by a competent engineer. a competent engineer would have put the transmit coil in an lc circuit tuned to the right frequency and thus made it way more powerful while consuming way less electricity. this is essentially an electric heater that radiates a small magnetic field.
We didn't need some fancy electronic locking device to stop trolleys leaving the car park (translation to American: carts leaving the parking lot)
..
Instead each trolley stacked up in the waiting area had a small mechanical lock that attached a pin to the trolley in front by a chain. In order to release the next trolley in line you had to insert a $1 coin, which was retained in the lock. When you finished using your trolley, you locked it back up again and your coin was returned. No high faluting electronics, a built in incentive to return the trolley, and no mysterious lockups.
Of course trolley wheels have been designed since day one to lock up without any fancy electronics inside them
I am Slashdot. Are you Slashdot as well?
These systems are used to keep people from taking carts past the store parking lot. Generally there is a painted line indicating how far you can go before the 'boot' will activate.
I don't understand how I keep seeing K-mart trolleys miles and miles from the nearest K-mart, but it explains the need for the 'boot' system.
All the carts in my local are already locked up, and they have no 'boot'. I was suprised to hear that a store in the world actually has functioning shopping carts, or at least ones without two wonky wheels out of four.
A positive attitude may not solve all your problems, but it will annoy enough people to make it worth the effort.
I think a better target would be the vibrating coasters that signal "your table is ready". If you could somehow set up all of those to go off at the same time on a Friday night you might...have them all going off at the same time on a Friday night! Drive-by mayhem!
Um, did you RTFA? Look at the signal, it's obviously an encoded byte. You would prefer to create a system where you have to rebuild the entire system if they change the code? She even explicitly mention that different stores have different codes, and that she included a simple switch to choose which signal to broadcast... seems like smart engineering to make your interface as easily modified as the system it's interfacing with.
Did you look at the hardware or read the descriptions of the design? It's pretty clear that she is not at all afraid of circuitry, and even included *many* disclaimers showing people places where if they didn't follow the electronics design properly they could be seriously injured.
Senseless vandalism. Swell. How laudable. Life is tough enough, but how about locking up some wage-earner's cart, after he has suffered under the hands of a sadistic boss, just wanting to get some grub and go home. Delightful.
Mod down people who tell people how to mod in their sigs
But what if you have a pacemaker, and you're really, really short?
Whoever designed level 61 in Frozen Bubble is a sadistic bastard.
Best.Troll.Thread.Ever.
Appended to the end of comments you post. 120 chars.
"can the cost of putting a remote control boot, sensors, transmitters etc. really cheaper than losing some carts?" Obviously, yes, that is why stores pay big bucks for these systems. Remember, they don't just lose a few carts, they lose all of them one at a time. They have to hire people to cruz neighborhoods looking for them and bring them back. Those they do find are often worse for the wear. Ones they don't find wind up rusting in creeks and abandoned, broken in alleys and fallow yards. Locking shopping carts help prevent neighborhoods from being littered with these abandoned carts brought home on one-way trips by people who can't be bothered to buy a "granny cart." The addition of locks to my local shopping center's carts has quickly eliminated those carts from being strewn about by people walking home with groceries. The newer systems are much better than earlier iterations that use purely mechanical devices triggered by small "speed bump" like berms which rimmed the parking lot. These new systems are more reliable and have fewer false triggers--well, until now :-)
Note, I support walking to the store but I don't support stealing the cart just because it is convenient to push home--and no, most of those people pushing carts home are not fragile elderly people, at least not in my area, so that isn't the issue. And no, nobody ever takes them back, either. If they did, it wouldn't be as big a deal.
Why didn't they just build the device to always lock when there's no signal? A transmitter in the store emits a continuous signal that keeps the wheels unlocked. When you take it out of the parking lot and go out of signal range, the wheels lock up.
Seems a bit more prank proof that way.
Camping on quad since 1996.
The carts are part of the culture.
The system is grossly skewed towards the interest of the cart-owners, who abuse their control over the implements.
We have the right to take the carts away for our convenience (fair use) — and it is not "stealing", because we always plan to bring them back some day. It is stupid and unethical for the supermarkets to fight their customers over this, especially the single mothers (who have never gone shopping) among them.
SMAA (SuperMarket Association of America) and similar oppressive institutions world-wide will, no doubt, try to suppress this new invention, so all freedom-fighters must start mirroring the just released information on their computers.
In Soviet Washington the swamp drains you.
Yep, that's exactly what it's aimed at.
Used to work for the corporate side of a large food & drug retailer in the US; those shopping carts, wobbly wheels and all, cost on average about $120 each - and that's before the wheel lock systems were put in place (no doubt that has driven the cost up).
The ironic thing here is that some of the supermarkets have parking spaces outside the lot, but the carts don't roll outside the lots, so sometimes people can't get their shopping back to their cars. On the flip side, I watched one lady try to steal one of these carts - she got about 3/4 of a block away with it, and it was quite a struggle for her. Clearly she hadn't read the signs that said the cart wouldn't work outside the parking lot. It also was clear that what was in the cart wasn't her shopping.
Loss prevention is big business. This is what happens when people steal from local stores - the stores end up having to put measures in place that inconvenience everyone.
Insanity is a gradual process; don't rush it.
Basic human contact and interaction with your neighborhood is now a thing of the past folks. It's 2007 now, why the hell should I still have to know who that idiot living next door is?
True, but come to think of it, I'd probably use a microcontroller too. Low part count and cheap enough; I can get an attiny13 for about $1.7 where I live.
Maybe true: no 2 year committment to ATT, but perhaps a 1 year committment in the local state penitentiary :-). Well, this is probably better than to be with ATT, so GO FOR IT!
Either way, you're going to get fucked.
"Ladies and gentlemen, my killbot features Lotus Notes and a machine gun. It is the finest available."