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DIY USB Servo-Guided Water Gun
An anonymous reader writes "What better way is there to learn something than by making your own DIY gadget? Here's a new video showing how to use a common hobby servo, in conjunction with a small water pump, to create a USB controlled water gun! You can use your keyboard to aim and fire at an unsuspecting passerby. Both fun and educational, this project looks like a great DIY weekend project for any IT guy, wanting to make sure people think twice before asking a stupid question!"
Are you saying this doesn't matter? Legions of Wicked Witches will be stopped by this new weapon. Fill it with holy water and we may survive the vampire hoard.
This is all that matters.
Oh wait, nevermind, they're just trying to sell their kit. You might as well buy an Arduino since it's cheaper and has more applications. The only thing it lacks compared to the other is an LCD screen, but I figure it makes up for it by having a big community.
No existe.
whaddya think the "S" in USB stands fer, huh?
There is a fine line between being a cultivated citizen and being someone else's crop. - A. J. Patrick Liszkie
Can't you see... If one person builds one, then another will have to build one as well to defend themself. And, so, it escalates. Then comes the larger more powerful water gun. Then the mobile water gun. Then a brilliant but misguided developer creates an artificial intelligence. Building such a weapon will ultimately lead to IT armageddon. Think of the children!
Sexy?
Fill it with holy water
Kids today are not evil enough. Fill it with a mix of 3-methyl-1-butanethiol, 2-quinolinemethanethiol, or similar mercaptans (http://en.wikipedia.org/wiki/Skunk#Anal_scent_glands). Even using a dilute solution, your victim will have no friends for a week.
It might even keep the kids off your lawn.
Those who can make you believe absurdities can make you commit atrocities. - Voltaire
vampire hoard
Are you suggesting there is someone out there stockpiling vampires in case of a vampire shortage?
That's probably the worst brushless dc controller ever built. As you can see in the video the circuit cannot recover from too low rpm of the motor. He mentions better waveforms at the bottom of the site, though.
A proper sensorless BLDC controller measures the back EMF at the undriven coils and uses that information to figure out which coils to drive. Also you don't need a common ground for the coils, instead the polarity should switch when both ends of a single coil have the same potential. Of course it's possible that each of the coils actually has a third contact in the middle.
Properly driving a sensorless bldc motor is quite an interesting challenge for microcontroller programming. You'd need the analogue input and 3 PWM channels. Probably 3 digital outputs, too to switch the polarity.
In other words: I'm taking apart a harddrive right now.
Surely this stuff should be on the idle section of slashdot!
If I want DIY servo controlled stuff I can go to http://www.hackaday.com/ or http://www.hackedgadgets.com/ or http://www.hacknmod.com/ or even http://www.instructables.com/
To do something right, you often have to roll up your sleeves and get busy.
It's like beer, only less so.
Oh, so it's like American beer.
No. Absolutely not. Nobody is doing that.
Completely unrelatedly, does anyone know if butchers will deliver blood directly to your basement? I'm never quite sure how to ask.
DRM: Terminator crops for your mind!