Remote measurement of blast wave propagation

Patent metadata

Field	Value
Publication number	US-11079293-B2
Application number	US-201715721870-A
Country	US
Kind code	B2
Filing date	Sep 30, 2017
Priority date	Sep 30, 2017
Publication date	Aug 3, 2021
Grant date	Aug 3, 2021

Abstract

The method and system disclosed herein allow pressure profile data to be collected remotely from multiple autonomous sensors without entering the blast radius. The system obtains a GPS synchronized time value for detonation and obtains subsequent synchronized pressure data sets overtime from multiple independently functioning remote and correlates that data from each transducer with the initial detonation event.

First claim

What is claimed is:

1. A distributed Autonomous Pressure Profile Recorder (APPR) system for measuring multiple blast measurements from various locations, which is a distributed computer system comprised of:
a master sensing unit with a recorder which records a sensed detonation signal including a sensed detonation time T 0 when a circuit breaks in response to a detonation, said master sensing unit being highly synchronized to within less than a thousandth of a second to an external GPS signal wherein said external GPS signal is a pulse per second electrical signal that has a width of less than one second and accurately repeats once per second;
a plurality of APPR apparatuses placed varying distances from a blast source, each comprised of:
a pressure transducer, wherein said pressure transducer is configured to output pressure reading P, said pressure reading P sampled at time T 1 . . . n to produce P 1 . . . n ;
a recording component;
a processor which compares P 1 . . . n to a threshold value and activates said recording component when P 1 . . . n exceeds said threshold value;
a pressure profile data structure which stores time values T 1 . . . n for each P 1 . . . n larger than said threshold value; and
a clock which is synchronized to said external GPS signal and an APPR memory component for storing said pressure profile data structure for each of said plurality of APPR apparatuses; and
an external computer having a memory which stores data from said plurality of APPR apparatuses and data from said master sensing unit and wherein said external computer receives APPR data packets and correlates each of said APPR data packets with said sensed detonation time T 0 to complete a blast profile data structure containing time values, pressure values, and GPS coordinates from each of the plurality of APPR apparatuses.

2. A method for measuring a blast wave propagation implemented using a computer processor and memory storage, comprised of the steps of:
receiving a sensed detonation time T 0 , wherein T 0 is synchronized to an external GPS signal to within less than a thousandth of a second wherein said external GPS signal is a pulse per second electrical signal that has a width of less than one second and accurately repeats once per second;
receiving a signal to invoke a recording function;
performing a recording function in one or more APPR apparatus of claim 1 to record transducer pressure and time value outputs, wherein said time value outputs are synchronized to said external CPS signal;
storing P 1 . . . n over T 1 . . . n with GPS coordinates in a blast profile data structure; and
associating said sensed detonation time T 0 with said blast profile data structure to create a complete blast profile.

3. The method of claim 2 which further includes the step of transferring said blast profile data structure to memory of an external computing component.

4. The method of claim 3 wherein said external computing component iteratively processes said blast profiles from each transducer to produce a wave propagation data set.

5. The method of claim 4 wherein said external computing component processes said blast profiles to graphically represent said blast wave propagation.

6. The method of claim 2 which further includes the step of filtering said pressure and time value outputs using a P threshold value.

7. The method of claim 6 which further includes the step of storing filtered pressure values P 1 . . . n and corresponding time value T 1 . . . n for each of said P larger than said P threshold value.

Assignees

• United States of America—US Army
• Us Army

Inventors

• Stephens Catherine S
• Grey Clifford E
• Fuentes Roland
• Watkins Larry

Classifications

• G01L5/14 Primary

  for measuring the force of explosions; for measuring the energy of projectiles · CPC title

• F42D5/04

  Rendering explosive charges harmless, e.g. destroying ammunition ({F42B39/14 and F42B39/20 take precedence } ; extracting primers, dismantling ammunition F42B33/04, F42B33/06 {; chemical deactivating of explosives C06B21/0091}); Rendering detonation of explosive charges harmless · CPC title