Method and apparatus for detecting and measuring laps and gaps in composite materials

• US 5,963,660 A
• Filed: 09/26/1996
• Issued: 10/05/1999
• Est. Priority Date: 09/26/1996
• Status: Expired due to Term

• Current Assignee: The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: Cranfill, Robert E., Koontz, Jan S.
• Primary Examiner(s): Boudreau, Leo H.
• Assistant Examiner(s): Werner, Brian P.
• Application Number:
  US08/719,694
• Time in Patent Office: 1,104 Days
• Field of Search: 382/108, 382/141, 382/152, 382/173, 382/274, 382/286, 348/86, 348/92, 348/88, 348/125, 356/384, 356/372, 356/237, 428/293.7, 428/608, 257/746, 250/559.05, 250/559.08, 250/559.19, 250/559.29, 250/559.42, 250/559.46, 364/468.17, 364/469.01, 364/475.09, 364/507, 364/559, 364/560, 364/561, 156/64, 264/40.1, 162/198, 162/263
• US Class Current: 382/141
• CPC Class Codes: G01N 2021/8472 Investigation of composite materials
• CPC Class Codes: G01N 21/88 Investigating the presence of flaws or contamination

Abstract

An electronic scanner having a light source and a light sensitive head is connected via a cable to a computer. The scanner head detects reflected light from the surface of the composite material and generates an electronic representation of the surface. A conventional software driver interprets the scanner output to produce an electronic bit-mapped image. The electronic image is then displayed so that gaps are readily visible. The electronic representation is also analyzed to determine the presence of laps and gaps, to measure gap widths, to measure the distance between points on the display, and to determine the percentage of the surface covered by fiber material. The electronic representation may also be stored for later analysis.

Claims

1. An apparatus for detecting laps and gaps between fibers of a composite material, comprising:

(a) a light source for illuminating the surface of the composite material;

(b) a scanner associated with the light source for scanning the surface of the composite material to form an electronic representation of the scanned surface wherein the representation of the surface is divided into pixels, each pixel having an intensity value relative to the amount of light detected when scanning a corresponding portion of the surface;

(c) a display associated with the scanner for displaying the representation of the scanned surface so that laps and gaps are visible;

(d) a processing unit; and

(e) a memory coupled to the processing unit, the memory at least temporarily storing the pixel intensity values and storing program instructions that control the processing unit, execution of the program instructions on the processing unit comprising;

(i) converting the pixels for at least part of the scanned surface to a binary representation indicating that either a gap or fiber material is present at the location corresponding to that pixel;

(ii) summing alternately the number of continuous converted pixels representing gaps and the continuous converted pixels representing fiber material to form values representing the number of continuous pixels of fiber and gap material; and

(iii) comparing the sums of continuous converted pixels representing fiber material with a mean fiber width value.

2. An apparatus for detecting laps and gaps between fibers of a composite material, comprising:

(a) a light source for illuminating the surface of the composite material;

(b) a scanner associated with the light source for scanning the surface of the composite material to form an electronic representation of the scanned surface wherein the representation of the surface is divided into pixels, each pixel having an intensity value relative to the amount of light detected when scanning a corresponding portion of the surface;

(c) a display associated with the scanner for displaying the representation of the scanned surface so that laps and gaps are visible;

(d) a processing unit; and

(e) a memory coupled to the processing unit, the memory at least temporarily storing the pixel intensity values and storing program instructions that control the processing unit, execution of the program instructions on the processing unit comprising;

(i) converting the pixels for at least part of the scanned surface to a binary representation indicating that either a gap or fiber material is present at that pixel;

(ii) summing alternately the number of continuous converted pixels representing gaps and the continuous converted pixels representing fiber material to form values representing the number of continuous pixels of fiber and gap material; and

(iii) comparing the sums of continuous converted pixels representing gaps with a gap tolerance value.

3. An apparatus for detecting laps and gaps between fibers of a composite material, comprising:

(a) means for scanning the surface of the composite material to form an electronic representation of the scanned surface wherein the surface is divided into pixels, each pixel having an intensity value relative to the amount of light received when scanning a corresponding portion of the surface;

(b) means associated with the scanner for displaying the representation of the scanned surface so that laps and gaps are visible;

(c) a processing unit; and

(d) a memory coupled to the processing unit, the memory at least temporarily storing the pixel intensity values and storing program instructions that control the processing unit, execution of the program instructions on the processing unit comprising;

(i) converting the pixels for at least part of the scanned surface to a binary representation indicating that either a gap or fiber material is present at the location corresponding to that pixel;

(ii) summing alternately the number of continuous converted pixels representing gaps and the continuous converted pixels representing fiber material to form values representing the number of continuous pixels of fiber and gap material; and

(iii) comparing the sums of continuous converted pixels representing fiber material with a mean fiber width value.

4. An apparatus for detecting laps and gaps between fibers of a composite material, comprising:

(a) means for scanning the surface of the composite material to form an electronic representation of the scanned surface wherein the surface is divided into pixels, each pixel having an intensity value relative to the amount of light received when scanning a corresponding portion of the surface;

(b) means associated with the scanner for displaying the representation of the scanned surface so that laps and gaps are visible;

(c) a processing unit; and

(d) a memory coupled to the processing unit, the memory at least temporarily storing the pixel intensity values and storing program instructions that control the processing unit, execution of the program instructions on the processing unit comprising;

(i) converting the pixels for at least part of the scanned surface to a binary representation indicating that either a gap or fiber material is present at the location corresponding to that pixel;

(ii) summing alternately the number of continuous converted pixels representing gaps and the continuous converted pixels representing fiber material to form values representing the number of continuous pixels of fiber and gap material; and

(iii) comparing the sums of continuous converted pixels representing gaps with a gap tolerance value.