Method for heating and controlling temperature of composite material during automated placement

A method of forming a composite article from composite tape, the method comprising:

• guiding the composite tape onto a surface of a substrate and pressing the tape against the substrate in a compaction region such that the tape conforms to the contour of the surface of the substrate and is adhered thereto;
• and
• irradiating an area defined by opposing surfaces of the tape and of the substrate proximate the compaction region with a field of light energy generated by a laser diode array to heat the tape and substrate, wherein the laser diode array is controlled such that a greater amount of heat energy is applied to the opposing surface of the tape relative to the amount of heat energy applied to the opposing surface of the substrate.

A method of forming a composite article from composite tape, the method comprising:

• guiding the composite tape onto a surface of a substrate and pressing the tape against the substrate in a compaction region such that the tape conforms to the contour of the surface of the substrate and is adhered thereto;
• and
• irradiating an area defined by opposing surfaces of the tape and of the substrate proximate the compaction region with a field of light energy generated by a laser diode array to heat the tape and substrate, wherein at least two tapes are simultaneously fed to the compaction region and placed onto the substrate at different feed rates, and wherein the laser diode array is controlled so as to produce a different amount of heating of one tape relative to the other to compensate for the different feed rates.

A method of forming a composite article from composite tape, the method comprising:

• guiding the composite tape onto a surface of a substrate and pressing the tape against the substrate in a compaction region such that the tape conforms to the contour of the surface of the substrate and is adhered thereto;
• and
• irradiating an area defined by opposing surfaces of the tape and of the substrate proximate the compaction region with a field of light energy generated by a laser diode array to heat the tape and substrate, wherein the tape is guided and pressed onto the substrate by a tape placement head and the laser diode array is fixed relative to the tape placement head such that when the tape is guided and pressed onto a contoured surface of the substrate having a convex or concave curvature there is a change in orientation of the tape placement head relative to the substrate surface causing the angle of incidence of the light energy striking the substrate to change, and wherein the laser diode array is controlled so as to compensate for the change in incidence angle by varying a profile of the intensity of the light energy in the direction in which the tape placement head travels over the surface.

A method for making a composite article from composite tape material, comprising:

• guiding composite tape material onto a surface of a substrate and pressing the composite tape material in a compaction region such that the tape material conforms to the contour of the surface of the substrate and is adhered thereto;
• and
• irradiating an area of the tape material and the substrate proximate the compaction region with a field of light energy generated by a laser diode array, the array being divided into at least first and second diode groups which produce at least first and second light zones respectively irradiating first and second regions of the area, and wherein the first diode group is operable to irradiate the first region with light of a first wavelength and the second diode group is operable to irradiate the second region with light of a second wavelength different from the first wavelength, the first region absorbing the light of the first wavelength to a different extent than the second region absorbs the light of the second wavelength.