Remote controlling a car for Pyro, anyone want to help?

So I have a funny problem. A few members of my Pyro group are wanting to remote control a car and send it off a ramp into a wall of fire. But, while these guys have the smarts to make a wall of fire and the money to buy a car to burn. They don’t know squat about rigging a car to drive by remote control and this is where I hope the DMS can help.

Do we have anyone that has the knowledge or want to be a part of this?
@Team_Aerospace @Team_Automotive

This sounds awesome. I have experience in building RC … but I’ve never worked with a full sized car before.

I assume your looking for something more sophisticated than a rope on the steering wheel and a cinder block on the accelerator.

#macgyver4ever

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Mythbusters has multiple episodes where they have done this, and have covered enough of the process that they used to give you a general idea of what may be needed.

What a great idea. I have no experience with remote control cars, but would love to help out. I wonder if you could achieve the effect you need by slingshotting a non-working car? Please keep me posted.

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Its actually relatively straight forward, you need to figure out some way of actuating the brake and gas pedal and turning the steering wheel remotely.
I’ve seen it done with a stepper motor connected to the steering column via a chain and sprocket. Then you need linear actuators for the pedals, which I would probably diy-it by attaching a lead screw to some more steppers

What all that would actually look like depends a lot on the geometry of the car, but its certainly doable.

On the control side you would use a common rc reciever (I have one if you want it) that out puts a PWM signal based on the positions of the sticks. Read that with an arduino and output the proper stepper signals to drive the car.

If you need help i can lend a hand, of course. I also would love to meet these Pyro guys, sounds like a good group to know.

Adrian

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Awesome, glad to have the interested group.

I’m headed to Gillette Wyoming next week with Rex and Kovar the two guys who thought this up. I’ll get more specifics there.

I wouldn’t call that ridiculously cheap. All I’ve seen on the brushless ESC side that can give robotic control for hobbyiests is the Odrive, which $120ish for 2 channels.
We would need to gear down the brushless which adds mechanical complexity, especially since we don’t need a whole lot of travel. Encoders aren’t cheap either…

Unless I’m missing something, then please tell me because it would be game changing.

Edit. In this case we could probably get away with out encoders because we will just be driving by rc, we can just do it by eye with pwm ESCs. The point still stands on the mechanical complexity as far as I know, but I’m not a mechanical engineer so idk. It seems to me that we would be trading electrical complexity for mechanical complexity.

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Another info thread here:

Thus is a fairly common question, with lots of stuff available through Google searches.

Be careful with that actuator in field use. First, this would not have a default safe position. Second, it will have a linear movement. That means it will apply pressure at a constant rate, and will generally not produce a way to speed up the braking ability.

If the vehicle is going to move in a straight line, the easiest way is to tow the vehicle with a pulley located at the impact point. Allows for quick reset in the event a shot is aborted prior to pyro event.

If you absolutely have to have RC, then you probably want a pneumatic actuator with default safe.

I’m inclined go rc because remotely chasing people in a big field would be my ideal warm up before for the main event.

Anyway, good point on the brakes, we can do pretty much anything on the throttle but the brakes must be failsafe, robust and will need more force. Also an emergency shutoff interlock might be nice while we r in there.

On the subject of interlocks, when I was working on an electric racecar we had an inertial crash sensor that would isolate the battery in case of collision. We could use a similar sensor for the opposite purpose of puncturing the gas tank on the crash for a bigger boom lol. Food for thought…

Edit. Found the sensor

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If the car has cruise control, that can be used to work the throttle.

(Several paragraphs deleted)

Do you jokers have any idea just how close we are to ALL OF THE LIMITS that Homeland Security has set? All we have to do, is load the Pyrogen into the car instead of the wall, and we are lifetime members of Camp X-Ray. JHC!

So we show you how to build this freaking Death Machine, then just hand it over to a friend of a friend? No, I’m not in the mood to be “excellent” to each other any more. I don’t know your friends, Nick; and I surely don’t know their intensions. You need to rethink what it is that you’re asking. Oppenheimer went all nerdy and smoked 2 Japanese cities full of civilians, just to prove he was smart. I’m starting to get ill. I’m going to delete everything that I posted, now.

I mean I will be there the whole time (to watch it blow up is the whole point), this whole conversation has been under the assumption that there will be some notion of safety at this affair.

I’m sorry if y’all misconstrued the “chasing people” comment, my point is that if we are going to go through all the technical trouble I would like to have the opportunity to drive it normally.

And the over the rails extremist conspiracy theorists come out.

This is nothing like what you are saying. I run a non-profit that pull permits, get local AHJ approval, pull insurance, and hosts events where things like this can happen. We have members with the licensing and experience to do the fireworks both legally and safely.

The idea for the car was first to see what it would take to lift it with a slow explosive. The problem with that idea was the unknown amount of shrapnel that would be produced and how to view it safely. So instead of exploding the car, we shifted to a more Movie Magic style shot. This would be to jump a car through a wall of fire. We have been working on hybrid flame effects for years and have the process down well. We would produce a wall of fire for the car to fly through and then crash into the ground on the other side. This would allow many to see the process for a effect like this in person, while also doing it safely. The thing about professional fireworks is maintaining a practice for solving problems safely. This was intended to challenge our processes and possibly update or improve some of our best practices.

@Russell_Crow, it seems you may not be emotionally stable enough to work on a project like this with a group. Thank you for removing yourself before it was a larger issue.

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I don’t know if you saw the news yesterday. There was a terror attack in El Paso where a lot of people got killed.

The idea of rigging a full-sized car for remote control, and mixing in explosives, for people we don’t know, is not well advised these days.

As for licensing, here’s mine; show us yours.

Pull your pants up Russell, we aren’t playing those games.
This is the kind of events we put on.