Electronic apparatus for automatic control of the placing of material at a junction between surfaces

Apparatus to control the automatic placing of material along a junction between surfaces with reference to the form and position of the junction comprising:

• means to deposit material controllably movable progressively along the junction in response to a control signal,
• means to illuminate said junction in light of a specific wavelength,
• means for producing an image of the surfaces where material is next to be placed,
• said image producing means including information collection means linked to the means to deposit material to move with said means to deposit material to collect information to produce said image during controlled material placing movement along the junction,
• said image producing means further including means for removing from the collected image information interfering information resulting from illumination other than by said light source of specific wavelength, said removing means comprising a spatial frequency filter means including a tapped delay line to provide a specific impulse response to respond to information in the image from said light source representing the junction position together with means to extract from the response of the spatial frequency filter that portion of the image unambiguously defining the junction form and position, and
• means responsive to said image portion to derive said control signal during progressive material placing movement free of the need to handle said interfering information.