Target system giving accuracy and energy

• US 7,685,862 B1
• Filed: 04/25/2005
• Issued: 03/30/2010
• Est. Priority Date: 04/25/2005
• Status: Expired due to Fees

• Current Assignee: The United States of America As Represented By The Secretary of Agriculture
• Original Assignee: the united states of america as represented by the secretary of the navy
• Inventors: Hughes, Derke R., Feaster, Jeffrey T., Deshamais, Dennis F., Blackmon, Fletcher A.
• Primary Examiner(s): Caputo; Lisa M
• Assistant Examiner(s): DUNLAP, JONATHAN M
• Application Number:
  US11/116,169
• Time in Patent Office: 1,800 Days
• Field of Search: 73/121.1, 735/84, 738/625.9, 738/626.1, 73862627-862628, 273/372, 367/127
• US Class Current: 73/12.11
• CPC Class Codes: F41J 5/056 Switch actuation by hit-generated mechanical vibration of the target body, e.g. using shock or vibration transducers
• CPC Class Codes: G01M 7/08 Shock-testing
• CPC Class Codes: G01S 5/18 using ultrasonic, sonic, or infrasonic waves

Abstract

A target for a test range includes an impact plate having at least three strain sensors positioned on the plate. The sensors are connected to a data acquisition board for receiving a signal from each sensor upon impact of a projectile on the plate. The data acquisition board is joined to a processor for calculating impact location and energy. Optionally multiple sensors can be provided having different orientations for accounting for different strain components in the plate.

Claims

1. A target for a range comprising:

an impact plate for a projectile capable of absorbing the impact energy of the projectile without destruction having a region of expected impact thereon;

a first three sensors capable of substantially unidirectional strain measurement positioned on said impact plate and oriented with respect to the region of expected impact to measure strain created substantially parallel to an impact induced shock wave front;

a second three sensors capable of substantially unidirectional strain measurement positioned on said impact plate and oriented with respect to the region of expected impact to measure strain created substantially perpendicular to an impact induced shock wave front;

means for determining impact location joined to said first three sensors and said second three sensors; and

means for determining impact energy joined to said first three sensors and said second three sensors.

2. The device of claim 1 wherein said means for determining target impact and said means for determining impact energy comprises:

a data acquisition board having a plurality of channels with one channel joined to each sensor, said data acquisition board receiving a signal from each sensor and providing data related to said signal; and

a processor joined to said data acquisition board for receiving data, said processor being capable of calculating impact location and impact energy, said processor being capable of calculating impact energy from an experimentally derived sensor output amplitude to impact energy transfer function programmed in said processor.

3. The device of claim 2 wherein said sensors are strain sensors.

4. The device of claim 3 wherein said strain sensors are made from a piezoelectric material.

5. The device of claim 4 wherein said strain sensors are made from lead-zirconium-titanate.

6. The device of claim 1 further comprising data recording means joined to said means for determining impact location and said means for determining impact energy.

7. A target for a range comprising:

an impact plate for a projectile capable of absorbing the impact energy of the projectile without destruction having a region of expected impact thereon;

a first three sensors positioned on said impact plate outside the region of expected impact and oriented with respect to the region of expected impact to measure strain created substantially parallel to an impact induced shock wave front;

a second three sensors positioned on said impact plate outside the region of expected impact and oriented with respect to the region of expected impact to measure strain created substantially perpendicular to an impact induced shock wave front;

means for determining impact location joined to said first three sensors and said second three sensors; and

means for determining impact energy joined to said first three sensors and said second three sensors.

8. The device of claim 7 wherein:

said first three sensors are capable of substantially unidirectional strain measurement; and

said second three sensors are capable of substantially unidirectional strain measurement.

9. The device of claim 7 wherein said means for determining target impact and said means for determining impact energy comprises:

a data acquisition board having a plurality of channels with one channel joined to each sensor, said data acquisition board receiving a signal from each sensor and providing data related to said signal; and

a processor joined to said data acquisition board for receiving data, said processor being capable of calculating impact location and impact energy, said processor being capable of calculating impact energy from an experimentally derived sensor output amplitude to impact energy transfer function programmed in said processor.

10. The device of claim 7 wherein said sensors are strain sensors.

11. The device of claim 10 wherein said strain sensors are made from a piezoelectric material.

12. The device of claim 11 wherein said strain sensors are made from lead-zirconium-titanate.

13. The device of claim 7 further comprising data recording means joined to said means for determining impact location and said means for determining impact energy.