| 摘要: |
| 针对焊接稳定性定量评定困难的特点,提出了一种基于电流样本熵的焊接稳定性评定方法. 随着电信号稳定性降低,样本熵均值变大,样本熵标准差也变大,选用样本熵的均值与标准差的乘积来量化焊接稳定性. 讨论了嵌入维数、给定阈值和样本长度对样本熵的影响,对于研究的脉冲MIG焊电流信号,当m=2, r=0.08, N=2 000时,样本熵分布合理,计算所耗时间较小.最后做了三组脉冲MIG焊对比试验. 结果表明,通过样本熵的均值与标准差的乘积评定的焊接稳定性与实际焊缝质量效果吻合;在相同给定电流下,样本熵的均值与标准差的乘积越大,焊接稳定性越差. |
| 关键词: 样本熵 定量评价 焊接稳定性 焊缝质量 |
| DOI： |
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| 基金项目:广东省省部产学研资助项目(2013B090600098);龙岩市先进机械设计制造技术公共服务平台(2012LY01) |
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| Pulsed MIG welding stability evaluation based on current sample entropy |
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XIE Huangsheng1, FU Zhihe1, WANG Yuexin1, XU Min2, XUE Jiaxiang2
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1.School of Mechanical and Electrical Engineering, Longyan University, Longyan 364012, China;2.School of Mechanical and Automotive Engineering, South China University of Technology, Guangzhou 510641, China
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| Abstract: |
| Aiming at difficult features in welding stability evaluation, a kind of welding stability evaluation method based on the current entropy was proposed. The mean and the standard deviation of sample entropy and was increased when current stability decreased. The product of mean value and standard deviation of the sample entropy were selected to quantified the welding stability. The effects of embedding dimension, given threshold and sample length on the sample entropy were discussed. For the given pulse MIG welding current signal, sample entropy distributed reasonably and time consumed less when m=2, r=0.08, N=2 000. Three contrast pulse MIG welding experiments were carried out at last and the results indicated that the welding stability evaluated by product of sample entropy mean and sample entropy standard deviation was coincided with actual weld quality, high value of the product of sample entropy mean and sample entropy standard deviation reflected inferior welding stability when the current was tbe same. |
| Key words: sample entropy quantitative evaluation welding stability weld quality |
