From Website of Toi Lab.

"In old days, noises were so loud. Today, noises have become much smaller than the old days even in the offi ce environment."

It can be said that this is the result of working hard for noise reduction. On the contrary, however, "small noises" are now becoming obvious. Is it good to decrease the sound volume until no sound is heard? If so, no audible information can be obtained, even producing weird feeling. Then he wondered if the idea of sound quality improvement was needed. This was the motivation for him to start studying the concerned area, says Prof. Toi.

"In the beginning, we were designing comfortable sound for each product". Then it was converted to the idea like "let's make suitable sound depending on what is necessary in living environment or according to the time zones or purposes." Prof. Toi had come to pursue the stance to assume each of the sound source being a musical instrument and coordinate them so that people living there would not get tired or can feel them as comfortable acoustic environment (smart sound design).

In other words, the traditional approach was to manufacture something, and if the produced sound was bad, it would be regarded as uncomfortable sound and processed for noise reduction. On the contrary, he positioned production of sound to improve comfortability as "comfortable sound design". At the fi rst stage of manufacturing automobiles or household appliance, sound is determined to defi ne whether or not this contributes to the functionality of the product itself, for example, asking "is this comfortable to use if we make the sound like this?" To do so, however, it is necessary to evaluate the present sound. After that, the setting goal of sound should be decided. Then, a method has been formed to consider the whole thing throughout the process from evaluation to the feedback of design, for example, "How will the sound be changed by changing where in what way?", or "How should the design be changed to produce this sound?".

Research cases on acoustics in the Lab

When he established the lab 20 years and more ago, the term "comfortable sound" itself was hardly used. Therefore, he needed to explain from its defi nition even when he was making presentation in academic meetings. In recent years, however, the concept of "sound quality improvement" and "comfortable sound design" have penetrated so widely that they are ordinarily used.

On the other hand, "Acoustic Systems Laboratory" has about 10 undergraduate students and another 10 or so graduate students, and several researchers dedicated for joint research on the register. Regarding joint research with companies that the lab started to take in positively early, more than 10 themes are progressing at the same time in a year. Each theme is positioned as a project for 2 to 3 years. So far 200 and some 10 themes have been dealt in total.

One of the important facilities for these researches is an anechoic room. The Lab uses multiple rooms according to the purpose. They include two anechoic rooms as well as a semianechoic room capable of accommodating actual vehicles and large structures, which is the largest scale for a university in Tokyo. The Lab also utilizes wide-ranging ICT (information and communication technology). For example, they use software for oscillation analysis, acoustic analysis, and different kinds of numerical simulation; sensors to measure bio-information, acceleration, and sound pressure; measuring equipment to measure oscillation or acoustics, and various kinds of simulators.
Especially, combining and merging multiple software programs in their own way, the Lab is trying to draw evaluations from such points of view that have been overlooked so far, or feedback to the design based on these evaluations. "In fact, there are not so many elements to deal with sound in the mechanical system." Speaking of the world of sound, what are generally known includes architectural acoustics as well as electro-acoustics for deleting or making sound (active noise control and active sound control etc.). Based on precision mechanics, the Lab started with a study on noise that occurs from machines, refl ecting its specialty. In expanding its objects steadily, the Lab has been covering issues of sound in the areas of vehicles, offi ces, living spaces, and medical care and welfare.		Explaining sound design for living environment

In recent years, Acoustic Systems Laboratory had tendency to do various kinds of research on sound regarding automobiles using DS through joint research etc. Prof. Toi reveals that his fi rst frank impression about UC-win/Road was "being capable of creating motion pictures nicely, with comparatively affordable price compared with other software programs we have".

Several years ago, he came up with a research idea as follows: "Is it alright that the driver's seat, the passenger seat, and back seats have the same sound environment, or is it necessary to have different sound environments for each seat?" In trying to build up experimental environment for evaluating sound for each of "sound only", "sound and vision", and "sound, vision, and driving operation" in the laboratory, it is rather hard to handle without using a tool like UC-win/Road in the part related to vision and driving operation. In particular, when trying to add some driving conditions, the display and sound were required to change linked with the acceleration and deceleration of the vehicle. This made them consider introduction of UCwin/ Road to meet such needs.

Almost at the same time, as mentioned at the beginning, when he heard from the working group studying acoustic evaluation in vehicle driving using bio-information that they want to represent actual driving conditions more realistically, in Sound quality evaluation technical committee (Society of Automotive Engineers of Japan, Inc.), with which he had been involved from its establishment, he introduced UC-win/ Road to them, which was adopted as a result.

Experimental environment for evaluating appropriate alarm sound created with UC-win/Road (simulation executed by switching day and night, clear and rainy sky)

For example, for the scene where a person is running out of a side street, UC-win/Road is actually used to create environment to see at what timing the alarm sound should be made in advance for the driver to perceive the scene more safely. He says that he realized its convenience in that it is easy to switch day and night or clear and rainy weather. What's more, it was made easier to represent the travelling environment, which was rather diffi cult before. Additionally, since the created sham driving environment changes according to acceleration (rapid and slow) or based on the driving operation etc. for various kinds of events set on the route, it exerts excellent oneness. Furthermore, he evaluates that it can be a very strong tool since all logs are kept. Particularly, in the sense of seeing the change in sound environment accompanied by operational system, UC-win/Road is easy to use, and useful for constructing comfortable and functional smart sound design, says Prof. Toi.

On the other hand, he expects from an acoustic specialist's point of view that it makes it possible to raise the degree of freedom for sound such as sound quality control. At the present, one of the big challenges is to monitor human information. For example, if emotion can be monitored, appropriate sound environment and oscillation environment are to be created based on this. He says that what they should do from now in relation with automobiles is to build up environments that refl ect fi ve senses based on such monitoring.

Lab members around DS applying the experimental environment of UC-win/Road in the anechoic room