为探求镐型截齿旋转截割煤岩侧向载荷的统计规律及时频谱特性，实现其特征参量的定量提取与有效识别，利用多截齿参数可调式旋转截割实验台开展煤岩截割实验。采用最大似然估计法与希尔伯特变换Hilbert法，给出锐齿、棱齿和钝齿侧向载荷统计特征与时频谱特征的内在关联。结果表明：在截齿旋转角为零度、截槽对称的实验条件下，截齿侧向载荷概率密度函数曲线服从正态分布规律，截齿侧向载荷的方向具有明显的不确定性，绕y轴正、负半轴波动。其均值接近于零，不利于截齿的自回转运动。二维时频谱表明截割能量集中在5 Hz以内的低频区域，且可有效识别侧向载荷的时频特征。%This paper is a targeted effort to investigate the statistical law and time-frequency spectrum characteristic of the side load on conical pick cutting coal and thereby achieve quantitative extraction and effective recognition these characteristic parameters. The investigation involves experiment on coal rock cutting using multi-picks parameter adjustable rotary cutting test bench; and adoption of the maximum likelihood estimation with Hilbert transformation to obtain the internal connection between the statistical law and time-frequency spectrum characteristic of sharp,blunt and edges picks. The result shows that un-der the experimental condition where the rotation angle of pick is zero and the kerf is symmetric, the curve of probability density function of side load conforms to normal distribution;the side load has obvi-ous uncertain direction and fluctuates around y axis,and has the mean value close to zero, which goes a-gainst self rotary motion. The 2D time-frequency spectrum shows that the cutting energy is concentrated in the low frequency region within 5 Hz, allowing an effective identification of the time-frequency character-istics of lateral load.
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