Welding speed sensor

A light source travel speed sensor, comprising (a) a series of normalized light intensity sensors spaced a known lateral distance apart and sensorially directed towards sequential line segments along a lateral path of travel, the sensors operable for generating sets of contemporaneous electronic signals over time with each set including an electronic signal from at least some of the sensors indicative of the intensity of light emanating from a light source on the path of travel sensed by the sensor, (b) an electronic timer operable for measuring time intervals between generation of sequential electronic signals, (c) electronic memory in communication with the timer for receiving and recording time intervals measured by the electronic timer, and containing at least (i) spatial relationship data for the series of sensors including at least the lateral distance between sequential sensors, and (ii) a normalization factor for each individual sensor correlated to the individual sensor, and (d) a processor in communication with the series of sensors for receiving the sets of electronic signals generated by each sensor, and in communication with the electronic memory, the processor operable for determining (i) lateral location of a light source on the path of travel for at least some of the sets of electronic signals based upon the spatial relationship data, normalization factors and relative values of light intensity measured by at least some of the sensors, and (ii) speed of travel of the light source along the path of travel based upon at least two determined lateral locations of the light source and the time interval between the at least two determined lateral locations of the light source.