[Gilad] tipped us about his latest project, where he adds plenty of pneumatics and electronics into his wife’s car to remote control it.
The brake/throttle pedals are actuated by pistons controlled by electronic valves, and a standard DC motor is in charge of turning the wheel. The Arduino code tells us that the valves will be opened as long as the remote up/down channel is above/under given values. The frame is based on Festo aluminium profiles and we’re not sure where the mains used for the DC/DC converters is coming from. As the valves use 24V and the motor 12V, standard N-Mosfets and power relays are used for voltage conversion. The remote controller [Gilard] used is actually 20 years old, so the output signal of the receiver isn’t actually really clean.
We do hope to never see this car on the road….
It would probably be a good idea to wire up some sort of fail-safe that would apply the brakes fully if the receiver loses a signal from the transmitter.
That is assuming that he is crazy enough to actually control this car remotely.
You’d need a big, big field, and a very small gas tank.
Actually realistically, how would you stop it if it went out of control? I think a relay needs putting in somewhere, perhaps in series with the low-voltage side of the ignition coil. The problem is, in engines, most wires are high-current or high-voltage, and either will weld a relay shut.
Maybe beef up a potato bazooka to take it out.
Horn. and light relays have been handling high currents in automobiles for decades without the relays welding themselves shut. Generally the are single pole single throw devices, limit the use as simple fail safe without some creative thinking in some applications. Auto ignition circuits are both low voltage and low current, that a solid state solution could handle.
It’s called a fail safe, and if he built it right he has a system that will apply the brakes and kill the engine if it loses signal or if any other issues happen.
I’m a fan of explosives in it, It’s getting out of control, KABOOM!
most wires aren’t high current or high voltage at all! most of the wires are for small sensors and actuators. yeah you have the high voltage of the ignition coils and high current of a starter, but that’s just a couple of wires. anything under 30 amps is pretty trivial to control with relays reliably.
Most high-current stuff on cars is *CONTROLLED* by relays. Even the starter motor, at hundreds of amps, has a solenoid (and usually a fusible link these days).
The average auto relay is rated at 30 or 40A, ones for large loads (heated screen etc.) are ~70A.
There’s multiple ways to stop a car, but very few to reliably and safely STOP it. As long as the engine is turning, the alternator is generating electricity and can back-feed the ignition circuit. Cutting the battery feed can result in the alternator losing its reference for regulation, hitting 100v+ and toasting a lot of stuff.
The suggestion above, killing the low-voltage side of the ignition coil (these days, coil pack) supply is reasonable, but you still need some fail-safe way of applying the brakes. I would want a large spring pulling the brakes ON that must be held OFF by the controller, preferably on some sort of watchdog.
The inclusion of an ardunio does not fill me with hope for the competency or safety of this project, I suspect it would be ropey enough running a normal RC car (which may be a better test bed) or something marginally less lethal like a lawnmower (minus blades).
Couldn’t one just… disconnect power to the fuel pump?
Open up the fuse box of your car, it is full of relays. And the fuel pump almost always has its own relay.
Could work well in this endeavor http://usatoday30.usatoday.com/news/offbeat/2009-08-14-car-launch_N.htm
Mythbusters have done this multiple times.
And messed it up badly multiple times!
But not with an arduino!
3 zipties to a wooden steering wheel adapter driven like a pulley doesn’t exactly scream robustness.
You’re right – duct tape is a much better choice!
I thought that was a toilet seat!
Do you think his wife knows?
i wonder which is a better driver! ;)
Oh SNAP!
While she still owns that car she has the perfect excuse.
“Well if you hadn’t pissed around it with it …”
:)
Another poorly conceived arudino project. No error correction, no safety consideration, nothing.
This is why I don’t trust anything by software “engineers”.
Come on, dude…Everyone knows that software engineers are not engineers. A prairie dog is not a dog.
Yup. No such thing as a software engineer. You have to be Licensed and have the state and feds test you to be an engineer. Anyone telling you they are a software engineer, is simply trying to puff up themselves. They are just a code money, nothing more.
butthurt much?
Or they could be a, you know, government examined and licensed professional software engineer.
Engineers write shitty code.
Or they could just have a degree.
None of that is needed as long as the car has no fuel in it ;o
I agree. DIY stuff is fun to see when it simplistically works well. Something that is this dangerous and only half-baked just makes me shake my head. That steering setup in particular looks like it’s only going be good for a matter of hours.
Saints Row The Third comes to my mind…
Wow, I expect to see this again on Wednesday – as a Hack A Day FAIL!
that is not something i would leave for an am/fm radio like that.. i’ve nearly lost ‘cheap’ r/c cars in a few hundred feet with such old tech..
He obviously never heard of the CAN bus … that’d be so much easier .. and also controls the whole car!
Guess you never heard of it either
You must be a GM engineer.
On some cars it does…but as far as I know codeblocks doesn’t support it. I’d almost like to see this thing run…on an empty lot surrounded by Jersey Barriers. BTW….I think this might be the most negatively written article I’ve ever seen on this site.
Next, on Hackaday’s fails…
I hope there isn’t a child in the car seat during the fail.
… RC car rear-ends police cruiser… :P
The ardumobile