Modelling of incident light occlusion during gear measuring based on the line-structured laser sensor and analysis on its influence factors

Line-structured laser sensors used in gear measuring provide a new way to acquire the perfect 3-D information of the complicated tooth flank with modification. This method leads to a series of problems, such as incident light occlusion, multiple reflection, system calibration and so on. The incident light occlusion poses severe problem on the integrity of the gear flank data acquired by the line-structured laser sensors. To understand the influence of the incident light occlusion during the cylindrical gear measuring and improve the efficiency of the measurement, this article analyzes this problem in depth. According to the position relation between the line-structure laser sensor and the gear, the projection theory is used to illustrate the incident light occlusion process between adjacent teeth and the model of the occlusion is built up. Four experiments are conducted to verify the validity of the model. This model applies to the cylindrical gear with different parameters. The influence of the modification on incident light occlusion zone could be ignored. On the basis of this model, the influence of the offset and the setting angle of the sensor on the incident light occlusion problem is thoroughly discussed, which gives a guide to control route planning and data acquiring during measuring the perfect information of the tooth flank.