# US 7,608,985 B2 · Method of detecting acceleration in vehicles > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,608,985 B2 - Document ID: US7608985B2 - Status: Granted - Kind: B2 - Application number: 12/185,246 - Filed: 2008-08-04 - Published: 2008-12-18 - Granted: 2009-10-27 - Earliest claimed: 2007-01-30 - Assignees: Raytheon Company - Inventors: Terry M. Sanderson - Web page: https://patentgrep.com/patent/US7608985B2 ## 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 Piezomagnetic, magneto-strictive, or electro-strictive material particles may also be distributed throughout the structural material of the structural member, which serve to amplify and otherwise enhance the signals from the piezoelectric material particles. The piezoelectric, electro-strictive, magneto-strictive, and/or piezomagnetic material particles may allow the structural member to exhibit an electrical and/or magnetic response to forces on the structural member, such as accelerations. This may allow the structural member to function as a force sensor or an accelerometer. Signals induced by such external forces or accelerations may be taken from the conductive pickups and used for various operations, for example, for arming a warhead of a missile or for triggering passenger safety features such as air bags in automobiles. ## Claims ### Claim 1 A method of detecting acceleration in a vehicle, the method comprising: placing at least one conductive pickup on a structural member of the vehicle, wherein the structural member includes a continuous structural material, and a plurality of piezoelectric, piezomagnetic, magneto-strictive, and/or electro-strictive material particles in the continuous structural material; and receiving electrical signals from the at least one conductive pickup, wherein the signals are indicative of electrical fields in the structural member caused by stresses induced in the structural member by acceleration of the vehicle. ### Claim 2 (depends on 1) The method of claim 1, wherein the detecting acceleration is used to control arming of a weapon. ### Claim 3 (depends on 1) The method of claim 1, wherein the placing includes placing a plurality of piezoelectric material particles in the continuous structural material. ### Claim 4 (depends on 3) The method of claim 3, further comprising exciting at least some of the piezoelectric material particles. ### Claim 5 (depends on 4) The method of claim 4, wherein the exciting includes subjecting the structural member to an ultrasonic signal. ### Claim 6 (depends on 4) The method of claim 4, wherein the exciting includes subjecting the structural member to a vibrational resonance signal. ### Claim 7 (depends on 4) The method of claim 4, wherein the placing also includes a plurality of piezomagnetic, electro-strictive, and/or magneto-strictive material particles in the continuous structural material; and wherein the exciting includes enhancing excitement of the piezoelectric material particles through the plurality of piezomagnetic, electro-strictive, and/or magneto-strictive material particles that are also in the continuous structural material. ### Claim 8 (depends on 1) The method of claim 1, wherein the placing includes placing a plurality of piezomagnetic material particles in the continuous structural material. ### Claim 9 (depends on 1) The method of claim 1, wherein the placing includes placing a plurality of electro-strictive material particles in the continuous structural material. ### Claim 10 (depends on 1) The method of claim 1, wherein the placing includes placing a plurality of magneto-strictive material particles in the continuous structural material. ### Claim 11 (depends on 1) The method of claim 1, further comprising selectively triggering one or more events based on the electrical signals. ### Claim 12 (depends on 11) The method of claim 11, wherein the selectively triggering includes selectively arming a warhead based on the electrical signals. ### Claim 13 (depends on 12) The method of claim 12, wherein the selectively arming includes sending an arming signal to an arming circuit. ### Claim 14 (depends on 11) The method of claim 11, wherein the selectively triggering includes selectively detonating a warhead based on the electrical signals. ### Claim 15 (depends on 11) The method of claim 11, wherein the selectively triggering includes triggering one or more passenger safety features based on the electrical signals. ### Claim 16 (depends on 15) The method of claim 15, wherein the one or more passenger safety features include air bags. ### Claim 17 (depends on 1) The method of claim 1, further comprising detecting impact events by monitoring the electrical signals. ### Claim 18 (depends on 1) The method of claim 1, wherein the placing the at least one conductive pickup includes placing multiple conductive pickups placed at different respective locations on the structural member. ### Claim 19 (depends on 1) The method of claim 1, wherein the placing the at least one conductive pickup includes placing a conductive foil pickup on a surface of the structural member. ### Claim 20 (depends on 1) The method of claim 1, wherein the placing the at least one conductive pickup includes placing a conductive paint pickup on a surface of the structural member.