Thread: Box open/close circuitry help

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I'm working on a box that opens, plays sounds, then closes. I would like to trigger the opening with a motion sensor that opens the lid and the sounds start to play. I've ordered a recordable module for the sound and to open the lid I'm thinking about a cordless screwdriver (rewired for power), connected to all-thread for a make shift linear actuator to open the lid, hitting a micro switch to turn the screwdriver off. Will use an ice cube relay to start the ball rolling for the multiple items. I'm struggling with how to wait for the sound sequence to finish and reverse polarity to screwdriver to close the lid. Motion sensor would restart sequence. Any help would be greatly appreciated. Thanks

That's a complicated setup and there's more than one way to go about it...

Maybe the quickest, easiest, and fastest solution is to use a ready-made prop controller. This is also your most expensive option. I think you'll want something with at least 3 outputs and 1 trigger. I'm guessing you would need 2 outputs for the motor and 1 output to trigger the audio. You can also get a prop controller with built-in audio, (and use only a 2-output model) but that will probably add more to the cost and I think you said you already had a sound module. You may need to use an H-Bridge chip in order to reverse the motor. See below.

If you are good with electronics or have the time to learn the basics, you could build a circuit with one or two 555 timer chips (or use a 556 which is a dual-timer chip) with some capacitors and resisters to control timings and resets. You'll probably need to use something like an H-Bridge in order to make the motor work in both directions from the same circuit. I don't have any experience with H-Bridges, though, but you should research that.

Finally, if you're not afraid of some simple programming, you can use a microcontroller such as the Arduino. You'll still have to build a small circuit but you it's not too bad. I just did this for my spitting spider prop that I am working on. I basically use a Parallax PIR motion sensor and when motion is detected, I trigger a cheap $11.95 sound board to start playing and then several seconds into it, I start triggering a solenoid on & off which releases air from an air compressor that sucks up water from another tube and sprays it. You can see a video of the microcontroller in action with the circuit on a breadboard here:
http://www.youtube.com/watch?v=vv2-42o5yHs

Finished spitter with sound:
http://www.youtube.com/watch?v=M67_e...eature=related

Again, for your application you will need an H-Bridge IC in order to control the motor in both directions. I found a good tutorial on how to use an H-Bridge with an Arduino. See here:
http://itp.nyu.edu/physcomp/Labs/DCMotorControl


Good luck!

You could also add a time delay relay so that after your routine finishes it will clos ethe lid. I would use an off delay relay, it stays off until the specified time has elapsed, then with it wired to reverse the screwdriver it will lower the lid.

The spitting spider is great and maybe i'll build one of those for next year - should get some great responses - i can see it now!

Thanks for your help with my circuitry - i'll look into the H-Bridge IC - a pre-made controller would be too costly and takes the fun out of trying to figure it out

Happy haunting!

Thanks, was thinking about that, but still scratching my head.

By the way, Arduinos are relatively cheap. The Arduino Uno is < $30. And you can also use a Boarduino for < $18. Check Adafruit.com, sparkfun.com, Electronics123.com, etc.