# US 7,411,338 B1 · Structural material with piezoelectric material particles > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,411,338 B1 - Document ID: US7411338B1 - Status: Granted - Kind: B1 - Application number: 11/668,544 - Filed: 2007-01-30 - Published: 2008-07-31 - Granted: 2008-08-12 - Earliest claimed: 2007-01-30 - Assignees: Raytheon Company - Inventors: Terry M. Sanderson - Web page: https://patentgrep.com/patent/US7411338B1 ## CPC - G01N 29/12: by measuring frequency or resonance of acoustic waves {(measuring frequency or resonant frequency of mechanical vibrations or acoustic waves in general G01H1/06, G01H3/04, G01H13/00; acoustic resonators G10K11/04; vibration or shock testing of structures G01M7/00)} - G01M 5/0041: {by determining deflection or stress} - G01M 5/0066: {by exciting or detecting vibration or acceleration (vibration testing of structures G01M7/00)} - G01N 29/2475: {Embedded probes, i.e. probes incorporated in objects to be inspected} - G01P 15/0885: {by magnetostrictive pick-up} - G01P 15/09: by piezoelectric pick-up - G01N 2291/0231: Composite or layered materials - G01N 2291/0232: Glass, ceramics, concrete or stone - G01N 2291/0235: Plastics; polymers; soft materials, e.g. rubber - G01N 2291/0258: Structural degradation, e.g. fatigue of composites, ageing of oils - G01N 2291/02827: Elastic parameters, strength or force - G01N: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES (measuring or testing apparatus or processes other than immunoassay, involving enzymes or microorganisms C12M, C12Q) - G01M: TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR - G01P: MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT (measuring or recording blood flow A61B5/02, A61B8/06; monitoring speed or deceleration of electrically-propelled vehicles B60L3/00; vehicle lighting systems adapted to indicate speed B60Q1/54; determining position or course in navigation, measuring ground distance in geodesy or surveying G01C; combined measuring devices for measuring two or more variables of movement G01C23/00; measuring velocity of sound G01H; measuring velocity of light G01J7/00; measuring direction or velocity of solid objects by reception or emission of radiowaves or other waves and based on propagation effects, e.g. Doppler effect, propagation time, direction of propagation, G01S; measuring speed of nuclear radiation G01T; measuring acceleration of gravity G01V; {measuring or recording the speed of trains B61L23/00; speed indicators incorporated in motor vehicles B60K35/00; measuring frequency or phase G01R; traffic control G08G}) ## Abstract A load-bearing structural member has a continuous structural material with piezoelectric material particles mixed in throughout. The structural material may be any of a variety of suitable materials, such as polymer materials, composite materials, ceramic materials, or concrete. The piezoelectric material particles may be used for evaluating the soundness of the structural member, such as in quality control or structural health monitoring processes. The structural member may include one or more conductive pickups used for receiving signals from the structural member. The signals may be induced by introducing ultrasonic signals or vibrational resonance signals into the structural member. The response from such induced signals may be used for quality control purposes or structural health monitoring. Piezomagnetic, electro-strictive, or magneto-strictive material particles may also be spread throughout the structural material, to amplify and otherwise enhance the signals from the piezoelectric material particles. ## Claims ### Claim 1 A structure comprising: a load-bearing structural member that includes a continuous structural material, and a plurality of piezoelectric material particles distributed within the continuous structural material; and at least one conductive pickup attached to the structural member and operatively coupled to the piezoelectric material particles. ### Claim 2 (depends on 1) The structure of claim 1, wherein the piezoelectric material particles are distributed substantially uniformly throughout the continuous structural material. ### Claim 3 (depends on 1) The structure of claim 1, wherein the continuous structural material includes a polymer material. ### Claim 4 (depends on 1) The structure of claim 1, wherein the continuous structural material includes a composite material. ### Claim 5 (depends on 1) The structure of claim 1, wherein the continuous structural material includes a ceramic material. ### Claim 6 (depends on 1) The structure of claim 1, wherein the continuous structural material includes concrete. ### Claim 7 (depends on 1) The structure of claim 1, wherein the structural member also includes a plurality of piezomagnetic, electro-strictive, and/or magneto-strictive material particles distributed within the continuous structural material. ### Claim 8 (depends on 1) The structure of claim 1, wherein the at least one conductive pickup includes multiple conductive pickups placed at different respective locations on the structural member. ### Claim 9 (depends on 1) The structure of claim 1, wherein the at least one conductive pickup includes a conductive foil pickup. ### Claim 10 (depends on 1) The structure of claim 1, wherein the at least one conductive pickup includes a conductive paint pickup. ### Claim 11 (depends on 1) The structure of claim 1, wherein the at least one conductive pickup is on a surface of the structural member. ### Claim 12 A method of evaluating structural soundness of a structural member, the method comprising: placing at least one conductive pickup on the structural member, wherein the structural member includes a continuous structural material and a plurality of piezoelectric material particles in the continuous structural material; exciting at least some of the piezoelectric material particles; receiving electrical signals from the at least one conductive pickup, wherein the signals are at least in part caused by excitation of the piezoelectric material particles; and interpreting the signals to determine the structural soundness of the structural member. ### Claim 13 (depends on 12) The method of claim 12, wherein the exciting includes subjecting the structural member to an ultrasonic signal. ### Claim 14 (depends on 12) The method of claim 12, wherein the exciting includes subjecting the structural member to a vibrational resonance signal. ### Claim 15 (depends on 12) The method of claim 12, wherein the interpreting includes comparing the signals to signals obtained from evaluating other similar structural members. ### Claim 16 (depends on 12) The method of claim 12, wherein the exciting includes enhancing excitement of the piezoelectric material particles through a plurality of piezomagnetic, electro-strictive, and/or magneto-strictive material particles that are also in the continuous structural material.