The Application Of Adaptive Active Noise Control Theory In Tank Helmet

After60years’ development, with the “people-oriented” ideas is deeply inscientific and military weapons research, now military weapons research is not onlyemphasize the operational performance but also pay more attention to the ridingcomfort. Especially in recently years, as the adaptive active noise control theory is morematurer, noise problems caused by high-power engine and complexity of operations canbe solved more easier. This paper take reducing the noise hurt to tank crews as researchobjectives. After taking a comprehensive analysis of the noise in tank cabin, this paperdesigned a tank helmet model which is based on adaptive active noise controlalgorithm(LMS algorithm, filter-X LMS algorithm). In order to establish the physicalexperimental parameters, at first it used the MATLAB Simulation software analysisadaptive filter order and the algorithm convergence factor of the algorithm at first, thenused the physical experimental model to deal with the noise collected from the tankcabin which is in active service in PLA, and it achieved8-10dB noise reduction effect.The noise characteristics in tank cabin showed that tank cabin noise mainly containtwo kinds of sources which are airborne noise (such as mechanical noise, enginecombustion noise, exhaust noise, action noise) caused by the power system of theengine and vibration noise caused by the car body vibration, and majority noise’sfrequency is mainly concentrated in the50-1000Hz, Classified as low-frequency noise.But the traditional method of noise control (such as sound-absorption process, soundinsulation, vibration isolation and so on) is easy for high frequency noise, not for lowfrequency. So it applied adaptive active noise control method to solve the low frequencynoise in tank cabin. But if used the adaptive active noise control system in tank cabindirectly, the lineup of the secondary sound source, reference sensor and error sensor, theoriginal signal, secondary sound signal, error signal interfere with each other, that willcause time and space inconsistencies, and produce little effect in noise control in tankcabin. And the earmuff space is so small that the scheme ignored space inconsistentproblem and time inconsistent problem, so it supposed the function that using adaptiveactive noise control theory in earmuff space to deal with noise will relatively better.Finally, it used the experiment platform structures by TMS320C54x development boardand TLV320AIC3256audio decoder chip to validate theoretical analysis and computersimulation, it proved that the adaptive active noise control system applied to the tank helmet can achieve the desired result.