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This detects when and which drum the user has hit.

Hitting the drums: a velocity computational approach

You now have the positions of the LEDs in every frame. Our goal here is to detect when and which drums were hit so that the corresponding drums can produce their sounds.

Determining when a drum was hit

There are various innovative ways of tracking when the drums are hit. We chose to use a velocity computational approach due to its speed. Using this approach, you can look at the displacement of the LEDs in consecutive frames and calculate the velocity. Using basic physics, if the velocity changes from positive to negative (note that our coordinate system has the positive side of the y-axis pointing downwards) it implies a change in direction of the drumstick, or that a drum was hit. You should be able to figure out approximately which frame the drum was hit in. Since the hit point is returned in terms of two-dimensional coordinates, you can figure out which drum(s) are hit.

Variation in velocity with the movement of the leds

See if you can guess when drums were hit.

Determining which drum was hit

Position of the drums

[1: Cymbal; 2: BigTom; 3: Small Tom; 4: Floor Tom; 4: Snare]

The frame should be broken down into rectangles with assigned x and y coordinates where the drums are positioned. Our drum kit consists of the Crash Cymbal, the Big Tom, the Small Tom, the Floor Tom and the Snare. We check to see if the hit-point falls in the space assigned for any of the drums, and if it does, we move on to producing the sound and displaying the image on the computer screen. However, if the hit point is outside the frame, it is taken as a missed hit.

Questions & Answers

How we are making nano material?
what is a peer
What is meant by 'nano scale'?
What is STMs full form?
scanning tunneling microscope
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
The nanotechnology is as new science, to scale nanometric
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
what school?
biomolecules are e building blocks of every organics and inorganic materials.
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
sciencedirect big data base
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
characteristics of micro business
for teaching engĺish at school how nano technology help us
How can I make nanorobot?
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
how can I make nanorobot?
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
what is the actual application of fullerenes nowadays?
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
is Bucky paper clear?
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
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Source:  OpenStax, Tap that: a virtual drum kit. OpenStax CNX. Dec 19, 2007 Download for free at http://cnx.org/content/col10502/1.1
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