Phenomenon for lip motor boating?

In summary, the conversation discusses the concept of lip motorboating, which is when one exhales with their mouth closed causing their lips to flap and make a fart sound. The question is posed about what causes the lip vibration, specifically the cyclic battle between exhale pressure and stiffness/gravity. The conversation also mentions the possibility of related equations and the use of this effect in wind instruments.
  • #1
Randomly popped in my mind when trying to design microvalves and no idea where to post this... Lip motorboating is when you exhale with your mouth closed, causing your lips to flap like a horse and make a fart sound. My question is not what causes the sound but what causes the lip vibration. Any explanations (i.e cyclic battle b/w exhale pressure and stiffness/gravity) or EASY papers on this? I’d like specifics too (i.e is gravity negligible?)

Edit: Any related equations would be nice too - i.e (spitballing here...) static aeroelastic equations of motion.
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  • #2
If you are serious, the effect you describe is used to play a wind instrument.
The lips control a vibrating bit of wood held in the mouth in reed instruments while the musicians lips purse together and vibrate in an external metal mouthpiece in brass_instruments particularly horns.

The sound derives from air movement from the lungs while controlling lip positions. An excellent example from early wood instruments, the Didgeridoo provides resonance that reverberates in the player's (and listeners') chest.


1. What is lip motor boating?

Lip motor boating, also known as raspberry blowing, is a phenomenon where a person creates a vibrating sound by blowing air through their pursed lips onto another person's skin.

2. Why do people engage in lip motor boating?

Lip motor boating is often seen as a playful and affectionate gesture between partners or friends. It can also be used as a form of teasing or to express excitement or silliness.

3. Is lip motor boating a learned behavior or instinctual?

Lip motor boating is a learned behavior. It requires the coordination of muscles in the lips, tongue, and jaw to create the vibrating sound. Infants may accidentally make similar sounds, but it is not intentional.

4. Are there any health risks associated with lip motor boating?

In general, lip motor boating is not harmful. However, there is a potential risk of spreading germs or bacteria if the person blowing the raspberries has a respiratory illness or infection. It is always best to practice good hygiene and avoid lip motor boating if you or your partner are sick.

5. Can lip motor boating have a negative impact on relationships?

The impact of lip motor boating on relationships varies depending on the individuals involved. For some, it can be a fun and playful way to show affection. However, it is important to always respect boundaries and consent. If one partner is uncomfortable with lip motor boating, it should be avoided in the relationship.