Bridge movement detector

• US 5,801,314 A
• Filed: 04/11/1994
• Issued: 09/01/1998
• Est. Priority Date: 04/11/1994
• Status: Expired due to Fees

• Current Assignee: Shane F. Stoddard
• Original Assignee: Shane F. Stoddard
• Inventors: Irwin, John R., Stoddard, Shane F.
• Primary Examiner(s): Biegel, Ronald L.
• Application Number:
  US08/226,277
• Time in Patent Office: 1,604 Days
• Field of Search: 73/12.01, 73/12.04, 73/12.12, 73/786, 73/594, 178/18, 178/19
• US Class Current: 73/786
• CPC Class Codes: G01M 5/0008 of bridges
• CPC Class Codes: G01M 5/0033 by determining damage, crack or wear
• CPC Class Codes: G01M 5/0075 by means of external apparatus, e.g. test benches or portable test systems G01M5/005 takes precedence
• CPC Class Codes: G01M 5/0091 by using electromagnetic excitation or detection

Abstract

A damage detection system for detecting impacts to static structures such as bridges and the like. The damage detection system comprises an impact sensor assembly and impact analyzer system. The impact sensor assembly comprises a pendulum mounted for movement within the impact sensor assembly which is secured to a static structure. The impact analyzer system includes a micro-computer circuit, power means, visual indication means of the pendulum motion and relay circuit means to relay the type and magnitude of pendulum motion to a warning means.

Claims

1. A damage detection system for detecting damage to static structures from impacts thereto, said damage system comprising:

an impact sensor assembly for mounting to a portion of said static structure, the impact sensor assembly including a pendulum mounted for movement therein and means for sensing the location of the pendulum in response to said impact to said static structure, the impact sensor including;

a pendulum housing having the pendulum mounted therein,

a mounting member having the pendulum housing mounted thereon;

a leveling assembly for leveling the pendulum housing with respect to said static structure;

a gimbal mounting contained within the pendulum housing, the gimbal mounting having a portion thereof secured to the pendulum housing and having one end of the pendulum connected to another portion of the gimbal mounting to allow the pendulum to swing within the pendulum housing along two axis of motion; and

an impact analyzer system for detecting the motion of the pendulum to determine if the motion exceeds a predetermined condition of pendulum motion beyond acceptable limits of predetermined conditions of pendulum motion, the impact analyzer system including a micro-computer circuit, power means providing power for said micro-power circuit, visual indication means for indicating types of pendulum motion and relay circuit means to transmit a signal indicative of the type and magnitude of the pendulum motion.

2. The system of claim 1 wherein the impact sensor assembly further includes:

a circuit board mounted below said pendulum at the lower end of the pendulum housing, the circuit board being connected to the micro-computer circuit and the power source.

3. The system of claim 2 wherein the impact sensor assembly further includes:

a plurality of elongated rods, each rod being resiliently mounted with respect to a portion of the pendulum housing and extending from a portion of one end thereof, the plurality of rods supporting the circuit board mounted below the pendulum housing to maintain the circuit board in a predetermined relationship with respect to the lower end of the pendulum without the relative position of the circuit board and the lower end of the pendulum being substantially affected by ambient temperature changes.

4. The system of claim 3 wherein the impact sensor assembly further includes:

an array of light sources arranged in a predetermined pattern in the circuit board, each light source being connected to the micro-computer circuit and being illuminated by the micro-computer circuit in a predetermined order of illumination; and

photo-optical sensor means being located on the lower end of the pendulum for sensing light from a light source when the light source is illuminated when the pendulum is located thereabove, the photo-optical sensor means being connected to the micro-computer circuit.

5. The system of claim 3 wherein the impact sensor assembly further includes:

a light emitting diode installed in the lower end of the pendulum; and

a photo cell sensor means for sensing when the pendulum passes thereover, the photo cell sensor means being connected to the micro-computer circuit.

11. The system of claim 1 wherein the impact sensor assembly further includes:

a relay circuit to relay the type and magnitude of pendulum motion to another location, the relay circuit connected to the micro-computer circuit.

6. A method of detecting impacts to a static structure, said method comprising the steps of:

installing an impact sensor assembly on said static structure, the impact sensor assembly including a pendulum mounted for movement therein;

.

connecting the impact sensor assembly to an impact analyzer system for analyzing the motion of the pendulum, the impact analyzer system including a micro-computer circuit therein for analyzing the motion of the pendulum;

inputting a predetermined value in the micro-computer circuit which causes visual indication of response if the motion of the pendulum has exceeded the predetermined value;

providing a visual indication if the predetermined value of the motion of the pendulum has not exceeded the predetermined value input into the micro-computer circuit;

illuminating the light sources in the array of light sources individually in sequence;

storing the location of each light source of the array of light sources in the micro-computer circuit; and

determining when the photo-optical sensor in the pendulum has sensed an illuminated light source.

7. The method of claim 6 further comprising the steps of:

providing a visual indication if the impact sensor assembly installed on said static structure is out of level.

8. The method of claim 6 further comprising the steps of:

providing a photo-optical sensor the lower end of the pendulum; and

providing an array of light sources located below the pendulum.

9. The method of claim 6 further comprising the step of:

providing a indication if the predetermined value of pendulum motion has been exceeded when compared to the motion of the pendulum from said impact to said static structure such as bridges and the like.

10. The method of claim 6 further comprising the step of:

relaying the indication that the predetermined value of pendulum motion has been exceeded when compared to the motion of the pendulum form said impact to said static structure such as bridges and the like to another location through the use of a relay circuit connected to the micro-computer circuit.