I have been doing some 3D computer graphics modelling and I have observed a phenomenon I cannot find anything about. I am using Blender (free 3D program). I am also using "Just Color Picker" which is a free Windows tool that let's you check the hue/saturation/value (HSV) for any color on your...
Let's say you have a simple structure with two equal masses connected by a massless rigid baton of length L. Like this:
Imagine this structure is totally free in space. It is not hinged in any way. Then forces act on each mass in 2D (x,y). If you have the x and y force vectors acting on each...
Thanks guys. As per the NASA link then the most correct formula would be:
D = Coeff * airdensity * Area * 0.5 * V^2
I will use a billboard style approximation of area = diameter * length.
Appreciate all the clarification. That should work well enough.
This is really just for approximation...
Another way of defining reference area that made sense to me for drag of a string would be taking half of the surface area of the string fragment, since half is pushing against the air at any given time.
This would be:
A = (π d Δx)/2
Though obviously some of the area is pushing more than...
I am trying to understand an excerpt from an article describing the vibrations of a string (eg. guitar/piano) which reads as follows:
This is basically the wave equation with Δm representing a small piece of mass from an interval of the string and two forces added to the right side.
He...
Thanks Dale. That's sort of what I tried doing already but I didn't think about the possibility of doing it with even finer detail than per sample in the way you suggest. The problem is the "hammer/hand" was moving so quickly relative to the sample rate it was collapsing the spring almost fully...
Numerical is totally fine and probably desirable!
FYI, if you're curious, this is for simulating the collision of a piano hammer or guitar plectrum (both of which are typically modeled as a mass (ie. hand/hammer) connected to a spring (ie. plectrum/felt) impacting another mass (ie. string...
Thanks. Yeah I was figuring giving the spring mass would make it much harder. We'll leave it with no mass then.
I can try to know as much as I need to know. :smile: I never knew how to do imaginary math with Euler's formula or Laplace transforms last year and now to a limited extent I can (had...
Let's say you have two masses on either side of a spring. Mass 1 is connected to the end of a spring. The spring itself has no mass. Mass 2 is free in space. So you have:
[M1]-[spring] [M2]So it's more descriptive, I'll name the variables like you might in programming. Let's define...
A textbook gives an example of an ideal mass striking an ideal string here:
This is drawn as an equivalent electrical circuit as follows, where each R represents one of the two string segments the mass interacts with (ie. the string segment to the left of the mass and the string segment to...
Now I'm actually thinking of it from a different perspective.
The tension that is increased at the point of plucking or striking a string is the potential energy that then creates the audio output, right?
So actually the tension should decay very rapidly back to the baseline as the sound...
I am working on a guitar/piano synthesizer for my own interest. When a string is plucked or struck, tension increases causing a slight pitch bend and change in the inharmonicity. This change then settles as the note quiets down. Thus it is important to model how the tension rises above baseline...
Let's say you have an impulse of noise, eg. via a guitar string, or a resonant bandpass filter, and it decays naturally. If "1" is the maximum initial amplitude of sound, and "0" is no sound at all, what is the equation for decay of sound over time (x)?
Is it:
y = 1/c^x
Or y = 1/(x+1)^c
I...
I was able to find a website summarizing a damped wave equation for a circular membrane here:
where u is the amplitude of vibration of the membrane, r and are polar coordinates of membrane, a is the damping factor, c is the speed of a wave on the membrane...
I am trying to solve for the theoretical relative decay rates of the various (m,n) modes of an ideal circular membrane, if that membrane is excited momentarily by an impulse or deformation.
I would ideally like the decays of the (m,n) modes in dB/s.
Imagine a simple isolated drum head being...