Simple Beating Heart Mod

anthony22 · Post by **anthony22** » Sun Feb 26, 2023 12:22 pm

Has anyone experimented with beating heart modification? I don't mean like the expensive "breathing robot feature" of some manufacturers.

I mean something as simple as modifying a beating heart teddybear type thing, and putting in a doll, or putting something around a necklace or something to give the sensation and sounds of a beating heart.

Something like these products:
https://www.amazon.com/s?k=beating+hear ... _sb_noss_2

Seems like an interesting concept that I came up with. Maybe it's already been tried or discussed in another thread?

Anthony

timetraveler1 · Post by **timetraveler1** » Sun Mar 26, 2023 2:46 pm

i don't know if anyone has done this but it is a interesting idea , if someone did create something like this, the problem would be the sound part, the heart beat sound it's self is no problem because as you have shown toys already have it. the problem is unless it's a cloth doll material ( which is how the sound is heard so easily from the teddy bears etc. ) with a doll tpe, or silicon, their would have to be a open area where the sound could get through , i would think, that is ( unless the sound could be set very loud that it would be heard through the tpe or silicon skin. AND EVENIF THAT WAS DONE THE HEART BEAT WOULD NEED A WIRE RAN IN THE BODY TO A BATTERY SOMEWHERE. THAT COULD BE CHANGED. some electronic things are made in the back of doll heads. for access. i don't know if anyone has ever done this idea but i like the idea!

Post by **John Takshing** » Sun Mar 26, 2023 6:12 pm

timetraveler1 wrote: ↑Sun Mar 26, 2023 2:46 pm
some electronic things are made in the back of doll heads. for access. i don't know if anyone has ever done this idea but i like the idea!

Tailor · Post by **Tailor** » Sun Mar 26, 2023 7:19 pm

Low-frequency sound tends not to be absorbed as easily as high-frequency. I am not an expert on acoustics but I have picked up a little and it's a complicated subject.
Low-frequency sound waves are very long and can pass through matrial.
Hence, you hear mostly the base when the neighbors play music :drinking:

Can't remember if it was because the waves caused the material to vibrate at the same frequency and thus carry the sound and amplify it or if it just passed right through, probably both depending on the material. While short waves mostly bounce back in the room where the sound is played. High frequencies pass through a stuffed animal quite well but not a wall, for example.

Rubber has a good ability to absorb vibrations, but it's quite a thin layer of it inside a doll, so I'm guessing that the sound of the heart passes through reasonably well anyway. And don't forget that a real heart sound also passes through meat, muscle and fat which also absorbs the sound before you hear it.
So the sound you hear is probably relatively low frequency guess between 80-500hz.

Personally, I don't want to hear a pulse on my dolls but I think it's worth a try if you want this. If you operate it into the chest, you can either put the speaker close to the steel frame so it helps spread the sound, or you don't insert the speaker very deep at all to reduce the absorption from the silicone.

timetraveler1 · Post by **timetraveler1** » Sun Apr 02, 2023 8:41 pm

yes that sounds like a good way it could be done .good idea.

Witchetty · Post by **Witchetty** » Sat Apr 22, 2023 6:45 am

The heart piece is pretty weak in those since they're designed for cotton, but for the doll you could substitute with something stronger like an egg vibe or other insertable that has a heartbeat-like setting. If you implant it near the surface, it could work well. Vibration definitely seems like the way to go, but you could also try a mini bluetooth speaker - I have one that's only about 1" - and play really bass-y sounds through it. Maybe a stock heartbeat sound, looped with low pitch/bass boost. Obviously low sounds don't go through tiny speakers that well, but some of the newer ones are impressive.

Technician · Post by **Technician** » Sat Apr 22, 2023 7:42 am

This is pretty cool, a 10W amp onboard would be loud enough to hear, also can play different files so it could emulate different heart rates.

https://www.electronics123.com/shop/fn- ... 8267#attr=

I was also thinking a variable square wave generator might do something neat, with a pulse at like 1hz or 0.5hz run to a speaker it should make something like a heartbeat, and be able to speed up or down.