基于红外透过滤光片的P-GMAW熔池图像传感

Vision sensing of weld pool for P-GMAW by an infrared transmitting filter

被动视觉熔池传感技术常采用窄带滤光片使熔池辐射较强而弧光较弱的某波长范围内的光进入摄像机,以抑制弧光干扰获得较清晰的熔池图像.在分析熔池辐射光谱分布、电弧光谱分布和摄像机光谱敏感曲线等影响熔池成像因素基础上,文中提出采用红外透过滤光片拍摄熔池图像,最大程度利用近红外波段熔池辐射能量高而电弧辐射弱的特点,同时透光波长范围的增加也避免了摄像机敏感性不足而导致的成像质量下降问题.P-GMAW熔池传感试验结果表明,红外透过滤光片能够较好的抑制弧光,在脉冲电流峰值和脉冲电流基值期间均可获得清晰和细节丰富的熔池图像.

A narrowband filter is used in passive vision,which allows light in a narrow wavelength range to transmit to format a clear image of weld pool.In the range of wavelengths,the radiation of weld pool is relatively high while the arc emittance is relatively low,so the disturbance of the arc is suppressed.In this paper,infrared transmitting filter is proposed for weld pool imaging based on the analysis of influencing factors,such as the spectral distribution of weld pool radiation,the spectral distribution of the arc emittance,and the spectrum response of the camera.Infrared transmitting filter makes maximum use of the advantage that at near-infrared band the weld pool radiation is high and the emittance of the arc is weak.At the same time,light in the larger wavelength range can transmit the filter,so image quality degradation due to the insensitivity of the camera is avoided.Experimental results of plused gas metal arc welding(PGMAW) process shown that clear weld pool images with details can be captured by the infrared transmitting filter during both the peak current period and the base current period of the P-GMAW process.