SONAR: The Next Frontier

a map of the seafloor created using sonar technology

A great example of computer science at work with other types of engineering is sonar technology. Sonar is found naturally in animals such as bats and sea creatures used to map out an environment that cannot be observed otherwise. It has been emulated by machines such as submarines to do exactly that. However, I believe that the technology can be taken further. Sonar could be used in acoustical modelling as well, scanning a room and mapping the room out, creating acoustic optimization. But first, it is important to have a full understanding of sonar.

Sonar stands for SOund Navigation And Ranging. The first sonar device was created in 1906, however, the theory behind it was being experimented with as early as 1822. There are two types of sonar: active and passive. Passive sonar is used to receive sounds not made by the device and therefore would not be useful in mapping out a room.

Active sonar works by transmitting a sound or “ping” that is emitted from the sonar device. When this “ping” hits an object, it reflects off of the object in many directions, including the direction back towards the device. Sonar technology records the time it takes for the sound to return thus measuring distance. For long distances, active sonar uses a lower pitch, which travels longer and resonates louder. In terms of measuring a room, the sonar device could ask the user to input a generalization of the room dimensions to determine what type of frequency should be sent out.  

There is a seafloor mapping sonar technique that would be optimal for mapping out a room called Multibeam sonar. This sends out multiple “pings” while the device moves to create a full map of the seafloor. This can be used in a similar way to map out each wall of a room, in case the room is in an odd shapes with walls that have windowsills or other inconsistencies. There is also Side Scan sonar that scans the ocean floor for objects that protrude from the ground. Side scan sonar continuously records the echoes produced and creates a sound picture of the sea floor. When the echoes are strong, it means that they are from hitting something hard. This is portrayed by a dark spot on a map. Contrastingly, when something is soft, the echoes are weak, and the spots on the map are light in shade.  This can be used if the user has a bed or other furniture that they will not be removing from the room to show how to properly adapt the environment to create optimal sound.

It is important to note that if sonar were to be used for mapping out a room for acoustical optimization, the technology would have to be modified to an air medium as opposed to water. This has already been somewhat accomplished by topographers who use sonar to map out land, however, it may need to be modified for an indoor environment.

Sonar is a developed technology that has helped in various aspects of life. It is adaptable and it can be modified to fit many needs, such as mapping out a room for acoustic optimization.

How to Become a YouTube Star!

Let’s face it, everyone is trying to be a YouTube sensation. A quick Google search of “girl singing on youtube” brings up a whopping 87 MlLLION results. A lot of the time, these Katy Perry wannabes just don’t have what it takes. But it is important to remember that the proper acoustical set up of a room could do wonders for a novice’s sound and in some cases could help a real star stand out.

My favorite YouTube sensation

        Here are tips to help YOU create your own home studio.

According to B&H Photo Video Pro Audio, the largest non- chain, home- recording company in the United States, there are many factors to take into account in terms of creating a recording from home. The optimal room for a home studio would be that in the shape of a rectangle with average height ceilings. This avoids inconsistencies in frequency responses. However, if the home studio is in a different shape than this, my device will show the user how to properly set up regardless. This would include putting the recording material in the corner of a square shaped room, thus also avoiding excessive sound reflection as well as maximize the space that the sound can be “thrown” in the room.

It is also important to place your equipment (i.e. desk with computer, mixing console, etc.) in the optimal position. This equipment should be places 20% away from the center of the room. My device will show the user exactly where to put their equipment.

Often times, particularly for rooms that are not rectangular in shape, it is important to obtain acoustical absorption material as well as diffusion material (often fiber glass) called bass traps for the home studio. The absorption materials take in high frequencies, reverberations, and overtones that can interfere with the integrity of the recording. These should be placed one the ceiling above the loudspeakers, on the wall across from the loudspeakers, and behind the loudspeakers. The bass traps deter low frequencies from collecting in corners and should be placed in every corner of the room. It is said that the home studio should be 50% covered with these acoustic materials. My software will help the artist properly place these aids rather than the artist having to spend hours referring to handbooks and internet articles with questionable credibility.

Now for those nitpicky readers out there, you may be wondering how this relates to computer science. There is software out there that creates acoustic models but there are none that assist in setting up an optimal one. My goal is to theoretically (at least) create a setup that will scan a room using SONAR technology, put that room into an acoustic model, and show the user how to set up that room for optimal sound.

Acoustical Engineering and Where It’s Going

Have you ever wondered why musicians perform where they do? Have you ever thought about why you can hear your obnoxious neighbors’ every move? The answer is acoustics. Acoustical engineering is a science that is often overlooked. When delving into the matter, it can be seen that there is much thought put into every aspect of designing a concert hall or amphitheater or even an auditorium, classroom, or apartment building.

“Sound is defined as a mechanical disturbance traveling through an elastic medium—a material that tends to return to its original condition after being deformed.” Sound can travel through many different mediums, not just air. Essentially, sound is emitted created by vibrations. The vibrating material moves inward and outward in the medium. When molecules collide with the outward movement, they are accelerated back into the medium with a greater speed and energy than normal. They then collide with more molecules, transferring their speed and energy onto them. At this point, there is a higher concentration of molecules in the area of the fast molecule because of their unusual speed. This process is called compression. Contrastingly, molecules that collide with the inward vibration lose speed and therefore transfer their lack of energy as they travel outward. This is called rarefaction. Check out these other terms that are used when speaking about sound.

http://science.howstuffworks.com/29843-understanding-sound-waves-video.htm

The technology of acoustical engineering has been around for a very long time. Think back to the Roman coliseums where philosophers would speak. Or the amphitheaters where Shakespearian plays were performed. These are all built in a closed, rounded manner. This is because of the most basic principle of acoustics: sound bounces off of material. If these performances were given in an open field, the sound would be (perhaps completely) lost.

New technology has brought us very far in terms of acoustics. Now there are computerized models that can be created that can show exactly how an environment will react acoustically. There is software that can electronically simulate the acoustics of a blueprint for a room before it is even built. This can take the guesswork out of system design, help eliminate costly mistakes and reduce installation time. Such simulators are highly desired and can be used for a multitude of applications, apart from just building a room. Here are some examples of the other very important applications of acoustical engineering:

Machinery: Such as lawn mowers. The use of a lawnmower can damage the human ear to a point where loss of hearing may occur. A softer lawn mower is always more desirable.

Automotive: Not only the sound created by speakers in a car but also the art of creating a vehicle that can somewhat keep out the ambient noise of the road but let the important sound, such as sirens, in.

Electronics: such as cell phones, televisions, and speakers.

Consumer goods: such as refrigerators, dryers, vacuum cleaners, hair dryers, and even toilets.

Aerospace: helicopter noise, take-off sound of a rocket, and sound transmission through a cockpit.

As you can see, sound is very present in everyday life. The new technology that has been developed to encompass this important aspect of society is ever growing to fit to the needs of the consumer, and will continue to grow further.

The Art of Sound Recording

Sound recording has become a staple in everyday society. It is easy to overlook the complexity and advancement in this technology when it is so readily available to us. However, when you look at the details of sound recording, it actually encompasses a rich history starting in the nineteenth and a strong modern concentration on computer technologies.

The History

Sound recording was first developed in 1857 by a man named Édouard-Léon Scott de Martinville. He essentially created a model of the inside of the human ear with a stylus that traced the audio frequency variations in air pressure onto a piece of paper covered in soot. This was only to be a visual representation of sound but it wasn’t long until Thomas Edison perfected the phonograph which etched grooves (different depths in the grooves for different frequencies) into a cylinder and was able playback the sound. This evolved into the gramophone, patented by Emile Berliner in 1887. His device used the vinyl record we are accustomed to seeing instead of a cylinder and instead of recording various depths, it etched into the disc horizontally, along the width of a disc. Electronic recording came around in 1925. This technique allowed the use of microphones and over-dubbing (recording a track on a disc, playing back that track so the performer can play with it and recording that on a second disc). This is when official studio recording was born. Then came magnetic recording. This process uses a magnetic material (such as the tape part of a cassette). Electric signals are sent from the sound and the signals magnify the tape in certain ways so as to emulate the sound made. This technology is what was used for cassette tapes.

Jumping ahead, digital recording first planted its roots in 1979. This type of recording used a technique called pulse-code modulation (PCM). In PCM , the amplitude of the analog signal is taken regularly at equal intervals, and each sample is rounded to the nearest value within a range of digital steps. This is where the CD, and eventually the mp3, come into play. This technique allows digitalization of music and when the mp3 technology was developed in the late 1990’s, it took over the audio recording scene.

The Process

When understanding digital sound, it is important to first understand what is being recorded. Below is the analog representation of someone saying “hello”. It represents the position of the microphone’s diaphragm (altered by the changes in pressure due to the produced sound) along the y-axis, as it progresses through time, x- axis.

The ultimate goal of digital recording is to create a record with high fidelity, similarity between the original and duplicate sound, and perfect reproduction, meaning the recording sounds the same every time it is played. To do this, the wave is converted into numbers, much like a high level programming code is converted to machine language. When playback is required, the numbers are converted back into the analog representation, amplified, and sent through the speakers to produce the sound. As long as the numbers don’t become corrupted, the sound will always remain the same, thus producing the most efficient and effective way of recording.

 

For more information:

http://electronics.howstuffworks.com/analog-digital.htm

http://ohda.matrix.msu.edu/2012/06/digital-audio-recording/

http://cool.conservation-us.org/byorg/abbey/an/an23/an23-2/an23-202.html

Disney World’s Newest Wish Granting Technology: MyMagic+

A recent trip to Orlando’s Walt Disney World has seriously sparked my techie interest. This is due to the new MyMagic+ technology, th1.1 BILLION dollar project that Disney world has been working on over the past five years. This project uses a MyMagic wristband as a universal medium for your entire Disney experience. The wristband acts as a park ticket, a hotel key, a FastPass, an optional credit card, and a collector of personal information.

These wrist bands use RFID (radio frequency identification) technology, the same technology used for the Florida SunPass system. The RFID tag is a technology that is replacing the tedious UPC codes that are used for scanning your products at the grocery store. These RFID tags are essentially intelligent barcodes that can communicate with an electronic reader that then gets transferred to a network. (more info here)

In terms of Disney’s usage of this, you simply put your wristband up to the reader, scan your finger print, and POOF! In true Disney magic fashion, you are quickly admitted into the park. In addition to this convenient entrance technique, you can also book your FastPasses (basically a “jump to the front of the line” pass) in advance and plan your trip accordingly. This helps visitors avoid the “where do I go next” hassle of a theme park that is dictated by which ride has the longest line and ultimately provides for a more enjoyable experience.

Most advanced about this new Disney method is the new information gathering that the wrist bands provide. The wristbands also contain Bluetooth technology. This technology interacts with certain hot-spot areas of the park. If an area is reading that too many people (each read by wearing a wristband) are in one area of the park, popular costume characters will move to a less concentrated area, thus dispersing the large crowds into more equal sections. Additionally, there is an option to add personal information to the wristband for a Disney park worker to scan. So not only can your put your credit card onto the band and not have to worry about carrying around a wallet or purse, you now have the option of your daughter’s favorite Disney princess to come up to her, greet her by name, and wish her a happy birthday; this all plays in to the “magical” experience of Disney.

There is some skepticism of the potential hacking of the system. The fact that valuable information such as credit cards can be stored on the band, creates the fear of hackers scanning your band with a smart phone and stealing the information. Disney has addressed this with the added precaution of requiring a pin for any transaction over $50, however, a bit more reassurance in terms of security would be greatly appreciated and has so far not been announced. The MyMagic+ project is currently in a beta testing stage and being offered to annual pass holders and resort stayers. It is being very well received by the public and seems to be the newest way to attend a theme park. As this technology becomes more common it will most likely become more present in everyday life.

Read More:

http://www.technobuffalo.com/videos/disney-mymagic-wristbands-first-look-d23-expo/

Well, writing…

“Well, writing novels is incredibly simple: an author sits down…and writes.

Granted, most writers I know are a bit strange.

Some, downright weird.

But then again, you’d have to be.

To spend hundreds and hundreds of hours sitting in front of a computer screen staring at lines of information is pretty tedious. More like a computer programmer. And no matter how cool the Matrix made looking at code seem, computer programmers are even weirder than authors.”
– Christopher Hopper