Science Buddies: "Ask an Expert"

Hi. I'm doing a 6th grade science "invention" project. It's going to be a gate that has a voice recording that reminds you to close the gate when it's open. I have a specific design question I'm trying to figure out...

I have a toy talking parrot that when you squeeze one wing you can record a message and when you squeeze the other wing it plays the message back.

I want to build a model gate that is hooked up to a circuit that connects to this talking parrot so that when the gate is opened the parrot will say my message ("please close the gate, please close the gate").

I understand that an electromagnetic relay might help me connect the gate circuit to the talking parrot circuit, but I don't understand HOW to do this or what parts I will need to build the circuits.

If I can extract the wires from the playback side of the talking parrot and I can build a small wooden gate, how do I need to wire these together to make this work?

And would you have any leads about where I should go to buy parts? Radio shack folks have not been very helpful.

I would be SO grateful for any help anyone out there can offer!

I have to figure most of this out this weekend, the whole thing is due in a couple of weeks, but I have to do a lot of supporting presentation materials as well.

Thanks!

This shouldn't be too hard to set up, I wouldn't think.

I'm guessing that the switch in the parrot's arm is closed when you squeeze it. That connects the 2 sides of the switch which triggers the recording.

There are numerous ways to build a switch (or just buy a normally closed momentary contact switch and use that). On easy way might be to have something like a clothespin that would be held open when the gate is closed, but which springs closed when the gate is open. Then you could put to wires or electrodes on the inside of the prongs so the circuit is completed when the clip/spring/whatever is allowed to close by the gate being removed from it.

Or, as I said, get a normally closed momentary contact switch from Radio Shack. A normally open switch is one where the switch is closed when there's no pressure on the switch, but once you push on it, the circuit is opened. This could be used much like the homemade version I described above.

lostinspace wrote:Hi. I'm doing a 6th grade science "invention" project. It's going to be a gate that has a voice recording that reminds you to close the gate when it's open. I have a specific design question I'm trying to figure out...

I have a toy talking parrot that when you squeeze one wing you can record a message and when you squeeze the other wing it plays the message back.

I want to build a model gate that is hooked up to a circuit that connects to this talking parrot so that when the gate is opened the parrot will say my message ("please close the gate, please close the gate").

I understand that an electromagnetic relay might help me connect the gate circuit to the talking parrot circuit, but I don't understand HOW to do this or what parts I will need to build the circuits.

If I can extract the wires from the playback side of the talking parrot and I can build a small wooden gate, how do I need to wire these together to make this work?

And would you have any leads about where I should go to buy parts? Radio shack folks have not been very helpful.

I would be SO grateful for any help anyone out there can offer!

I have to figure most of this out this weekend, the whole thing is due in a couple of weeks, but I have to do a lot of supporting presentation materials as well.

Thanks!

Hello, lostinspace!

I'd like to add some detail in addiiton to the post from Ray Trent.

First, I think there are some useful descriptions of switches at the following web site:

http://wolfstone.halloweenhost.com/Tech ... tches.html

This may help you get a better understanding of "normally closed" and so on.

Squeezing the switch in your parrot's wing is a little like connecting the ends of two bare wires together. The wires stay connected as long as you're squeezing the wing, and they become disconnected when you let go. That's why it's called "momentary".

You suggested that you might consider using an electomagentic relay. An electromagnetic relay is just a switch triggered by an electromagnet instead of a pushbutton or toggle lever. I think using one is a possibility, but the electromagnet part is built into the switch, and the electromagnet needs power. You'd have to design a circuit to control the electromagent, and I think it would be simpler to use a different kind of switch.

If you'd like to do a little reading about electromagentic relays, check out this site:

http://ourworld.cs.com/gknott5413/elect129.htm

In my opinion, your challenge is to figure out a way to either squeeze the parrot's wing when the gate opens (the mechanical option), or do the work of the switch when the gate opens (the electrical option).

The mechanical option would be to attach something to the gate that does the squeezing. A clothespin or other spring-loaded mechanical device might work. Maybe even a mousetrap! (You wouldn't spring it, though! You'd just use the spring mechanism!) You could figure out a way to mount the parrot and the spring mechanism such that while the gate is closed the wing is not squeezed, but when the gate is opened, the spring mechanism would close and make the parrot speak!

The electrical option would be to replace the switch in the parrot's wing with another kind of switch somehow connected to the gate. This would involve opening the parrot's wing, cutting the wires to the switch, and connecting them to another switch.

Mr. Trent's suggestion of using a normally closed momentary switch for the electrical option is a good one. You would need to mount the switch such that the gate would be pressing the switch's button when it's closed and release the button on the switch when the gate is opened. Since the switch is "normally closed", the gate pressing the switch opens the circuit and disconnects the wires. Opening the gate then releases the button and closes the circuit, making the parrot talk!

Mr. Trent also suggested using a clothespin. In this case, you could use a normally open switch or two bare wires. You could mount the switch or the wires such that the clothespin would squeeze the switch button or press the bare ends of the wires together. When the clothespin is squeezed, however, it releases the switch button or separates the wires. You'd then mount the clothespin such that the clothespin would be held open when the gate is closed, releasing the switch button or disconnecting the wires. When the gate is opened, the clothespin to would close, completing the circuit and causing the parrot to talk!

I hope this extra information helps you. Best wishes on your project!

Wow, thanks for the help with this! I'm going with my dad to Lowe's today to see if we can get all the parts we need.

I was thinking to do the electric switch way rather than the mechanical way because I couldn't figure out how to get the gate to pinch the bird's wing when it was open...but also because the electric way seemed more elegant. But I couldn't figure out how to do it.

I'll give it a try this weekend, but may have to email back with more questions.

What a great thing that this site exists!

Thanks again!