Automate a lid?

[Ted jones]

And no hazardous accumulator to leak, mess up your floor, and cut your fingers off.
Toodleoo!
Ron Hebbard

Details! Details......

 

[DBL]

Looking for some creative ideas: We are trying to rig up an effect where a large-ish and moderately heavy trunk lid opens and shuts itself several times (and this happens pretty rapidly -- not a very laborious and slow opening/closing). For complicated reasons, nobody can be hidden anywhere near it (or in it), and we need to move it around to various positions while the effect is used (so it can't be physically attached to something rigid). I tried a system with aircraft cable through flexible metal tubing (sort of like a larger version of a bicycle brake cable) but there's way too much friction to make it practical. I would be interested in pretty much any ideas (be they electronic, pneumatic, mechanical) so long as they are safe and not overly pricy (I realize this may not be possible). Any hints about where to source the required items would be helpful, too.

And, before you ask, yes, we are keeping people out of harm's way.

Thanks!

Look at frightprops.com. If fixed speed is ok, I'd use a pneumatic cylinder with a small CO2 tank (paintball tank?) hidden in the trunk.
Otherwise I'd look at a car window motor or a linear actuator (depending on weight and travel needed). RC4 products are excellent but you may not need that much control. There are some cheap on/off radio links available. Obviously you need to be sure no one can get hurt if the radio link malfunctions.

 

[Jay Ashworth]

Agreed. If the visuals work, a linear actuator is a great machine. Better than hydraulics in the case.

But put a circuit breaker in the drive wire in case it locks up.

 

[almorton]

RC4 products are excellent but you may not need that much control. There are some cheap on/off radio links available. Obviously you need to be sure no one can get hurt if the radio link malfunctions.

You may not need the control, but you do want a reliable link, which is why, if I have a choice, I go with RC4 (or City Theatrical? I have friends who use them all the time, again, for reliability) as they are proven products, whereas the cheaper stuff can get swamped by cell phone mush, radio mics, you name it. It's part of a risk assessment, of course.

 

[RC4Wireless]

Using the RC4 solution suggested above with 12V linear actuators would work similarly, with the advantage that the RC4 connection tends to be reliable, even with mobile swash from phones, and they have high current controllers available to control the actuator, just need a relay controlled by one of the "dimmer" channels to reverse the feed to the actuator. Alternatively, a pair of low current dimmers with a high current H-bridge driver to reverse the actuator could work. All powered from easily sourced12V rechargeable sealed cells.

A few years back we offered an RC4 receiver/driver with an H-Bridge built-in. It would have been perfect for this -- directly connect and go, set up and running in seconds, everything you need in one little unit. Unfortunately, we didn't get enough interest in that product to keep it in production. If having this kind of thing interests anyone, be sure to let people like me know. I'd love to see enough interest to put a wireless H-Bridge back into production.

Jim
RC4

 

[RonHebbard]

Looking for some creative ideas: We are trying to rig up an effect where a large-ish and moderately heavy trunk lid opens and shuts itself several times (and this happens pretty rapidly -- not a very laborious and slow opening/closing). For complicated reasons, nobody can be hidden anywhere near it (or in it), and we need to move it around to various positions while the effect is used (so it can't be physically attached to something rigid). I tried a system with aircraft cable through flexible metal tubing (sort of like a larger version of a bicycle brake cable) but there's way too much friction to make it practical. I would be interested in pretty much any ideas (be they electronic, pneumatic, mechanical) so long as they are safe and not overly pricy (I realize this may not be possible). Any hints about where to source the required items would be helpful, too.

And, before you ask, yes, we are keeping people out of harm's way.

Thanks!

@jds10011 How did you eventually achieve your goal and were you and yours happy with it?
Toodleoo!
Ron Hebbard