Acoustic homing
Encyclopedia
Acoustic homing is a system which uses sound
to guide a moving object, such as a torpedo
. Acoustic homing can be either Passive or Active in nature.
Using Passive, the system is designed to move either toward or away from a sound, and may also be designed to move only toward certain types of sounds to the exclusion of others.
While Active is a true Sonar
. The system emits a sound pulse, that reflects off objects and then back to the system. Where the system processes the echos to determine the proper response.
and microphones. If a transducer receives a sound louder than that received by the other transducer, the object turns in the transducer's direction. If the object is to manoeuvre in three-dimensional space, more than two transducers are needed. Typically, more than three transducers are used, and arrays of over 100 are not unknown. A large number of transducers allows for more accurate steering.
es. Torpedoes can be made to move toward ships using acoustic homing.
Sound
Sound is a mechanical wave that is an oscillation of pressure transmitted through a solid, liquid, or gas, composed of frequencies within the range of hearing and of a level sufficiently strong to be heard, or the sensation stimulated in organs of hearing by such vibrations.-Propagation of...
to guide a moving object, such as a torpedo
Torpedo
The modern torpedo is a self-propelled missile weapon with an explosive warhead, launched above or below the water surface, propelled underwater towards a target, and designed to detonate either on contact with it or in proximity to it.The term torpedo was originally employed for...
. Acoustic homing can be either Passive or Active in nature.
Using Passive, the system is designed to move either toward or away from a sound, and may also be designed to move only toward certain types of sounds to the exclusion of others.
While Active is a true Sonar
Sonar
Sonar is a technique that uses sound propagation to navigate, communicate with or detect other vessels...
. The system emits a sound pulse, that reflects off objects and then back to the system. Where the system processes the echos to determine the proper response.
Method
An object can be equipped with two or more acoustic transducers, which function as speakersLoudspeaker
A loudspeaker is an electroacoustic transducer that produces sound in response to an electrical audio signal input. Non-electrical loudspeakers were developed as accessories to telephone systems, but electronic amplification by vacuum tube made loudspeakers more generally useful...
and microphones. If a transducer receives a sound louder than that received by the other transducer, the object turns in the transducer's direction. If the object is to manoeuvre in three-dimensional space, more than two transducers are needed. Typically, more than three transducers are used, and arrays of over 100 are not unknown. A large number of transducers allows for more accurate steering.
Uses
Acoustic homing is useful in weapons, specifically torpedoTorpedo
The modern torpedo is a self-propelled missile weapon with an explosive warhead, launched above or below the water surface, propelled underwater towards a target, and designed to detonate either on contact with it or in proximity to it.The term torpedo was originally employed for...
es. Torpedoes can be made to move toward ships using acoustic homing.