车间环境下机器人语音控制的特征提取算法

Algorithm for extraction of features of robot speech control in the factory environment

针对移动机器人在车间实际工作环境中,由于噪声的影响导致对语音控制命令识别性能差的问题,提出了一种基于伽玛通倒谱系数和Teager能量算子混合特征提取的新算法。该算法用伽玛通滤波器代替抗噪性比较普通的梅尔滤波器,在提取伽玛通倒谱系数的过程中加入反映语音信号能量的Teager能量算子组成新的特征,并考虑语音信号的动态特性,将其与一阶差分参数融合组成混合特征;应用主成分分析法降维,将得到的混合特征用于移动机器人控制命令的语音识别系统。实验结果表明,在车间噪声以及信噪比为10 dB的环境下,混合特征的识别率较梅尔倒谱系数提高了12.20%,通过主成分分析法得到的混合特征的识别率提高了1.02%。

In the real working environment,the mobile robots have a poor recognition performance to speech control commands due to the noise effect.Aiming at this issue,this paper proposes a new algorithm based on the gammatone frequency cepstral coefficient and the mixed feature extraction of the Teager energy operator.This algorithm replaces the common Mel filter with the Gammatone filter.In the process of extracting gammatone frequency cepstral coefficients,the Teager energy operator reflecting the energy of speech signal is added to form a new feature,with the dynamic characteristics of the speech signal considered.It is combined with the first-order difference parameters to form a mixed feature.And the principal component analysis is made to reduce the dimension,and the final mixed features are used to the speech recognition system for control command of the mobile robot.Experimental results show that,in the environment of the workshop noise and signal-to-noise ratio of 10 dB,the recognition rate of mixed features is improved by 12.20% compared with the mel frequency cepstrum coefficient.The recognition rate of the mixed feature is increased by 1.02% when the dimension is reduced by principal component analysis.