Microwave sensor for identifying the surface properties of a workpiece and associated method
First Claim
1. A sensor for identifying the surface properties of a workpiece, the sensor comprising:
- a microwave generator for producing microwave signals at a predetermined frequency;
microstrip sensing means, electrically coupled to said microwave generator, for supporting propagation of the microwave signals produced by said microwave generator from a first end portion toward a second end portion and for transmitting at least a portion of the propagating microwave signals to the workpiece such that the workpiece can influence the strength of the transmitted microwave signals, the second end portion being spaced apart from and electrically connected to the first end portion;
detector means, electrically coupled to the second end portion of said microstrip sensing means, for detecting the propagating microwave signals at the second end of the microstrip sensing means; and
surface properties determining means, responsive to said detector means, for determining the surface properties of the workpiece based upon the strength of the detected microwave signals such that workpieces comprised of a conductive material, an insulative material and a conductive material coated with a radar absorbing material can be distinguished.
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Accused Products
Abstract
A sensor and method for identifying the surface properties of a workpiece includes a microstrip sensor for transmitting and receiving microwave signals and surface properties determining means for determining the surface properties of the workpiece, including the type of material from which the workpiece is constructed, based upon the strength of the detected microwave signals. The surface properties identifying sensor also includes a microwave generator for producing microwave signals at a predetermined frequency for transmission by the microstrip sensor and a detector for detecting the microwave signals received by the microstrip sensor from the workpiece. Thus, workpieces comprised of a conductive material, an insulative material and a conductive material coated with a radar absorbing material can be readily distinguished by the surface properties identifying sensor and method.
13 Citations
18 Claims
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1. A sensor for identifying the surface properties of a workpiece, the sensor comprising:
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a microwave generator for producing microwave signals at a predetermined frequency; microstrip sensing means, electrically coupled to said microwave generator, for supporting propagation of the microwave signals produced by said microwave generator from a first end portion toward a second end portion and for transmitting at least a portion of the propagating microwave signals to the workpiece such that the workpiece can influence the strength of the transmitted microwave signals, the second end portion being spaced apart from and electrically connected to the first end portion; detector means, electrically coupled to the second end portion of said microstrip sensing means, for detecting the propagating microwave signals at the second end of the microstrip sensing means; and surface properties determining means, responsive to said detector means, for determining the surface properties of the workpiece based upon the strength of the detected microwave signals such that workpieces comprised of a conductive material, an insulative material and a conductive material coated with a radar absorbing material can be distinguished. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
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10. A sensor for identifying the surface properties of a workpiece, the sensor comprising:
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a microwave generator for producing microwave signals at a predetermined frequency; microstrip sensing means comprising; a dielectric substrate for supporting propagation of microwave signals, said dielectric substrate having opposed first and second surfaces; and a microstrip sensor comprised of a layer of conductive material disposed on the first surface of said dielectric substrate for transmitting microwave signals produced by said microwave generator from a first end portion to a second end portion such that the workpiece can influence the strength of the transmitted microwave signals, wherein the first end portion is coupled to said microwave generator and is spaced apart from the second end portion, and wherein said microstrip sensor further includes a center segment extending between and electrically connecting the first and second spaced apart end portions; a detector, coupled to the second end portion of said microstrip sensor, for detecting the microwave signals on said microstrip sensor; and surface properties determining means, responsive to said detector means, for determining the surface properties of the workpiece based upon the strength of the detected microwave signals such that workpieces having different impedances to the propagation of microwave signals can be distinguished. - View Dependent Claims (11, 12, 13, 14, 15, 16)
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17. A method of identifying the surface properties of a workpiece comprising the steps of:
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transmitting microwave signals having a predetermined frequency and a predetermined power level to the workpiece; receiving microwave signals in response to the transmitted microwave signals; filtering the received microwave signals to remove received microwave signals having a frequency outside of a predetermined range of frequencies about the predetermined frequency of the transmitted microwave signals; and comparing the power level of the received microwave signals, following said filtering step, to high and low predetermined power levels such that workpieces which have different impedances to the propagation of microwave signals can be distinguished. - View Dependent Claims (18)
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Specification