Apparatus for judging and processing branches and or crossings for use in automatic curve tracing system

Claim 2

In an automatic curve tracing system comprising a detector for performing a round scanning operation along the periphery of an area containing a curve to be traced to provide information regarding the presence or absence and the position of said curve, means responsive to said information to move said detector in a predetermined direction over a predetermined distance to trace said curve and means to alternately repeat said round scanning operation and said movement of said detector to continuously scan said curve: apparatus for judging a branch and or crossing comprising means for storing the tracing direction and tracing forbidden directions as a result of storing the detected positions of said curve on said successive round scans; means for detecting a branch or crossing as the presence of said curve at more than two positions of any scan; means for storing as branch information the position and direction of points at a detected branch or crossing not determined as tracing and tracing forbidden directions; and means responsive to the continued detection of said more than two positions of any scan for preventing storage on subsequent scans of the same said branch information.

Claim 3

The apparatus according to claim 1 wherein said detector for perForming a round scanning operation includes means for sensing a predetermined line spot pattern on the periphery of said area to detect as plotted points spots which fall on said curve, and said means for detecting a branch or crossing is operative to determine the presence or absence of said branch and or crossing according to the number of said spots falling on said curve in one round scanning operation.

Claim 4

The apparatus according to claim 1 which further comprises means responsive to the end of a continuous curve tracing in the tracing direction for returning said detector to the stored location of said branch information; and means for selecting the stored direction of one of said points stored as branch information as the next tracing direction.

Claim 5

An automatic curve tracing system comprising a detector for performing a round scanning operation along the periphery of an area containing a curve to be traced to provide information regarding the presence or absence and the position of said curve, means responsive to said information to move said detector in a predetermined direction over a predetermined distance to trace said curve, means to alternately repeat said round scanning operation and said movement of said detector to continuously scan said curve, means to return said detector to a branching or crossing point when it completes the tracing operation in said predetermined direction after it has reached a branch or crossing and to cause said detector to begin to trace said branched curve or crossing curve, means to store information corresponding to the commencement of said tracing operation of said detector in the direction of said branched curve or crossing curve, means to erase said information when the scanning area does not contain said branching point or crossing point, and means to integrate the two-dimensional vectors relating the distance between said branching point or crossing point and a point at which the scanning operation of said detector is being performed.

Claim 6

An automatic curve tracing system comprising a detector for performing a round scanning operation along the periphery of an area containing a curve to be traced to provide information regarding the presence or absence and the position of said curve, means responsive to said information to move said detector in a predetermined direction over a predetermined distance to trace said curve, means to alternately repeat said round scanning operation and said movement of said detector to continuously scan said curve, means to return said detector to a branching or crossing point when it completes the tracing operation in said predetermined direction after it has reached a branch or crossing and to cause said detector to begin to trace said branched curve or crossing curve, means to store information corresponding to the commencement of said tracing operation of said detector in the direction of said branched curve or crossing curve, means to erase said information when the scanning area does not contain said branching point or crossing point, and means to integrate the two-dimensional vectors relating the distance between said branching point or crossing point and a point at which the scanning operation of said detector is being performed.

Claim 7

The system according to claim 4 which further includes means to process another branch or crossing newly encountered by said detector while it is tracing a branched curve or a crossing curve.

Claim 8

An automatic curve tracing system comprising a detector for performing a round scanning operation along the periphery of an area containing a curve to be traced to provide an information regarding the presence or absence and the position of said curve, means responsive to said information to move said detector in a predetermined direction over a predetermined direction to trace said curve, means to alternately repeat said round scanning operation and said movement of said detector to continuously scan said curve, and means to detect a crossing contained in said curve, said last mentioned means including means to determine a representative spot among a group of spots plotted during each round scanning operation, means to determine a direction to be traced and a direction in which the tracing is to be forbidden from said representative spots, and means to judge the phase relationship between said representative spots to determine said crossing point.

Claim 9

An automatic curve tracing system comprising a detector for performing a round scanning operation along the periphery of an area containing a curve to be traced to provide an information regarding the presence or absence and the position of said curve, means responsive to said information to move said detector in a predetermined direction over a predetermined direction to trace said curve, means to alternately repeat said round scanning operation and said movement of said detector to continuously scan said curve, and means to detect a crossing contained in said curve, said last mentioned means including means to determine a representative spot among a group of spots plotted during each round scanning operation, means to determine a direction to be traced and a direction in which the tracing is to be forbidden from said representative spots, and means to judge the phase relationship between said representative spots to determine said crossing point.

Claim 10

The automatic tracing system according to claim 6 which further includes means to discriminate the magnitude of the information regarding said representative spots.