I found the biggest cylinder we have at work today.
the bore is 250mm and the stroke is 1100mm
ok ok its $2k, but it can lift, nae, throw 3000kg.

Pity the frame of the car would buckle under the opposing force though.
or would it?
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You could probably have some sort of a skid plate to transmit the 10 ton or so of force directly into the ground rather than into the car chassis.

You would want around a 50 litre buffer. I would hate to think of the size of the valve.

I would like to see a car 5 m into the air.
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the control valve you would need could be just a 3 port. the weight of the cylinder and arm on it would well and truly be enough to pull it back to home.

I wonder, could you use the cars suspension. the skid plate could be mounted under the car reasonably low to the ground. when the cylinder is activated the weight forces the car down, pressing the plate to the ground.
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Two of the vids here are to ilistrate how easy it might be to rc a car.
the top gear one is just funny.

http://www.youtube.com/watch?v=O7jHxXmzHmQ&NR=1

http://www.youtube.com/watch?v=-JL9vFOu4SQ

http://www.yikers.com/video_real_remote_control_car.html
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Never doubt that a small group of thoughtful, committed citizens can change the world; indeed, it's the only thing that ever has.

They've done a R/C combat car in Scrapheap Challenge in 2001, although they didn't build really destructive weapons apart from big poles as spikes (which did the most damage) and they used a scoring system where you get 10 for the sides, 20 for the rear, 30 for the roof and, in the third round, 100 for a yellow target.50 points for the opponent if you go out of the ring.
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It seemed like a good idea on paper...

I watched that last night - it had potential but was pretty lame in the small arena size. I think it would make sense to develop a fairly universal and "quick fit" RC interface that could be changed between cars - that would make it much easier for people to get started. It would also be much easier if people used auto transmissions.

It would also be really, really, really expensive. Those videos all had high power pneumatic control systems...
EDIT: and you don't know how much in scrapheap is real or not.. they get engineers to fix things up.
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YEAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAH

they didn't fix that leaky ass "speedboat" rofl
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Mechanical engineers build weapons, civil engineers build targets

they probably tried xD
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YEAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAH

id imagine youd just make a plate with the pnuematic or electric actuators on a board that you could just weld onto the floor pan in a few minutes and for the steering wheel just make a clamp around the steering column that the motor attaches too or something.

but yeah a huge area with big 100kmh rams would be so intollerably awesome
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That car video with the pneumatics has to be the hard way to do it! Much easier and cheaper to use a 'jumbo servo' and linear actuators. What I don't get is that everybody tries to adapt the existing human controls - I would be hacking the pedals off and working direct with the hydraulics where possible and also cutting off most of the steering column.

We wouldn't be needing the seats or much of the dashboard, so all that would go as well to make room for mounting the driving interface.

quote:

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Originally posted by dyrodium:

EDIT: and you don't know how much in scrapheap is real or not.. they get engineers to fix things up.

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if you get a car with OBD im sure some smart ass could knock up an interface so you could literally just plug the thing in and drive it,

gear changing on an automatic could be selected, drive by wire controlled and i guess power assisted braking also. just leaves the steering. maybe you could rely on the power steering alone..

but who would throw a car like that out

or we could just have a big demo darby
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http://www.youtube.com/user/HyzerGlen - Videoooozzz

Just had a think about this; you could do all the control of an auto car or a manual in one gear with two Roboteq controllers set up for servo mode. an AX1500 could do two pedals and an AX3500 could do steering and another pedal or gear shift. No exactly cheap, but a very easy off the shelf solution.

Another thing; taking the return springs off the controls and using shorter, smaller actuators would cut costs and complexity.

There is only one car thats electronicised enough out of the box to drive by plugging a computer in.

Cant remember the name off hand but its drive and steer by wire, i think the brakes are fairly conventional though. Its one of those supercompact city cars.

Theres only a few very late model cars that are throttle by wire. The ecu might well control 98% of everything but the foot pedal is still cabled to the butterfly valve in most cars. An EFI diesel might be easier to do, as i recall they don't have a butterfly valve.

Electric power steering is only just coming into main stream cars and hydraulic systems (as i recall) rely on a bar bending in the power steering assembly to do the power assist, so you have to turn the wheel to get the power steering to do anything.

Same sort of thing with power assisted brakes, The only thing that actually applies the brake without the person putting their foot on the pedal is traction control, electronic brake assist applies the brakes harder depending on how fast you press the pedal down.

ODB is really just for reporting and setting stuff about the engine, timings, injector durations, sensor readings etc.
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