Do You Know Your Trailers?
Over the road trucks make noise as the tires cause friction on the roadway. Many cities have found this to be aggravating and have built huge sound walls deflecting the sound waves away from neighborhoods near such freeways, tool ways and highways. This is one option to keep the NIMBY element happy in their perceived quality of life.
The sound waves bounce off the walls and stay out of the housing areas. Some cities such as PHX, AZ are experimenting with different road way surfaces which dampen noise, they actually work real well, unfortunately other such projects with surface technology fall short and actually cause increased friction on the tires of vehicles and therefore you trade off reduced efficiency on the cars and trucks for the quite feature. This is bad because you are using more fuel and creating more pollution increasing wear and tear on the vehicles to save noise. Then you have to ask which is more important, clean air or noise pollution.
Which the EPA is also looking into and adding to its requirements and we will soon see massive additional legislation. Cars for instance in CA new exhaust law are 95 decibels. There is no doubt that an OZZY OZBORNE will effect your hearing if you go to concerts, but freeway noise from larger vehicles such as over the road trucks is more of a nuisance. Although folks, if you go to the store and your favorite product is not on the shelf, well that too can be very aggravating and quite a nuisance.
Noise and acoustics is a science and we know how sound travels and where it is traveling too and with roads and airflows associated we do know the direction of the sound as it relates to the direction and speed of vehicles. Stealth aircraft have noise dampeners and sound rooms for recording have ways of keeping sound in. Sound can also be directed as in the special microphones, which are worn by TV people. custom trailer axles
Sound can be amplified and heard long distances as in spy equipment. Sound waves can be made to be very directional. Both in sending and receiving. Radio Telescopes and Surveillance technologies also use sound waves. Some day Radio Telescopes will be put on the Moon and on satellites to hear and protect us. A sound occurs and immediately we will be able to pin point it’s exact location and thus once this occurs and the technology is actually here, Arthur C Clarke will be proven correct once again. Now we can mount mini-units on aircraft and balloons to hear the ground and pick up tid-bits of information and intelligence. Georgia Tech has a balloon, full controllable which has a cell phone antenna in a sphere.
Much work has also been done in the ability to use voice commands and voice recognition by eliminating multiple back ground noise. This assist the NSA, multi-terra byte gathering cell phone conversations for Homeland Security and being able to identify specific voice patterns, inflections, key words, etc, this data can be analyzed instantaneously by computers working in grid. Since all this technology exists, it is now possible to attain much of the sound leaving the tires of a truck.
There are ways to incorporate structural integrity and support structures of the under frames of tractor-trailers and the bobtail trucks to capture or dampen sound. By dampening sound from escaping and collecting that sound which remains we can use this sound to power up small devices, which can save lives and add to the efficiency of the vehicle. For instance, running network sensors, keeping 48 volt batteries charges to the needed levels, all of which means less horsepower is needed to run the vehicle and charge batteries.