This is my ultrasonic sensor, during the first days of the radar residency i have been doing some experiments with this to find out how it works – essentially i am hoping to use it as a way of creating a human echo-locating device. essentially it seems that this measures the distance between an ultra-sound pulse and its echo. we connected this up to a oscilloscope to see how obstacles looked in terms of the sound reflection…
Apparently, Shrews are the only terrestrial mammals known to echo-locate [and the Tenrecs of Madagascar]. The shrews emit series of ultrasonic squeaks.
“Human echolocation is the ability of humans to sense objects in their environment by hearing echoes from those objects. This ability is used by some blind people to navigate within their environment. They actively create sounds, such as by tapping their canes or by making clicking noises with their mouths. Human echolocation is similar in principle to active sonar and to the animal echolocation employed by some animals, including bats and dolphins….Some blind people have described the phenomenon not as a learned method of navigation, but as an inherent and intuitive extra sense. For example, a blind person could walk past a line of trees and feel a “pressure” at their side as they passed each tree. The cause of this would be the echo of the sound of their footsteps; however, they may not consciously be aware of this mechanism, only that the phenomenon exists and can often be relied upon to detect obstacles.”
Pauls experiment investigates how dolphins detect sound using the jaw bone – this box has metal rods inside in a line [aproximatly representing the allignment of teeth in a jawbone] – so as the sound wave travels through the channel, the rods act as a filtering device – or at least that is the hypothesis [very briefly]. Apparently dolphins use their jawbone as a way of honing in on the direction of certain sounds.