Sensor powered event logger

• US 7,747,415 B1
• Filed: 12/22/2006
• Issued: 06/29/2010
• Est. Priority Date: 12/22/2005
• Status: Active Grant

• Current Assignee: Hottinger Bruel & Kjaer Incorporated
• Original Assignee: MicroStrain, Inc. (Spectris PLC)
• Inventors: Martin, Frederic P., Arms, Steven W., Townsend, Christopher P., Hamel, Michael J., Churchill, David L.
• Primary Examiner(s): Wachsman; Hal D
• Assistant Examiner(s): Suglo; Janet L
• Application Number:
  US11/644,038
• Time in Patent Office: 1,285 Days
• Field of Search: 702/189, 702/42, 702/33
• US Class Current: 702/187
• CPC Class Codes: F41A 17/06 Electric or electromechanical safeties F41A17/04, F41A17/08 take precedence
• CPC Class Codes: F41A 19/01 Counting means indicating the number of shots fired
• CPC Class Codes: G01D 9/005 Solid-state data loggers
• CPC Class Codes: G01L 5/0052 measuring forces due to impact G01L5/0061, G01L5/14 take precedence; impact testing of structures G01M7/08; impact testing of material G01N3/00
• CPC Class Codes: G01P 1/127 for acceleration values

Abstract

A system includes a structure and a circuit. The circuit is mounted to the structure. The circuit includes a sensor, a non-volatile memory, and a voltage sensitive switch. The memory and the voltage sensitive switch are connected for recording an event sensed by said sensor. The recording only uses power derived from the sensor. One embodiment of the circuit includes a processor connected for receiving a signal derived from the sensor. In this embodiment the non-volatile memory is connected to the processor for receiving and storing data derived from the signal. In one embodiment a first energy storage device is connected to receive energy from the sensor. The voltage sensitive switch is connected for releasing energy from the first energy storage device when energy stored in the first energy storage device exceeds a threshold. The processor and the non-volatile memory are connected for receiving power from the released energy.

Claims

1. A system comprising a structure and a circuit, said circuit mounted to said structure, said circuit including a sensor, a non-volatile memory, and a voltage sensitive switch, wherein said memory and said voltage sensitive switch are connected for recording a single event sensed by said sensor, wherein said sensor generates power during said single event, wherein all power used in making said recording is derived from said sensor during said single event, wherein said voltage sensitive switch is connected to prevent charge from being transferred to said memory until a voltage derived from said sensor exceeds a threshold.

2. A system as recited in claim 1, wherein said voltage sensitive switch is connected for providing power to said memory when said voltage derived from said sensor exceeds said threshold.

3. A system as recited in claim 1, further comprising a first energy storage device, wherein said voltage sensitive switch is connected for providing power to said memory when a voltage across said first energy storage device exceeds said threshold.

4. A system as recited in claim 1, further comprising a processor, wherein said voltage sensitive switch is connected for providing power to said processor when said voltage derived from said sensor exceeds said threshold.

5. A system as recited in claim 4, wherein said processor is connected for receiving a signal derived from said sensor, wherein said non-volatile memory is connected to said processor for receiving and storing data derived from said signal.

6. A system as recited in claim 4, further comprising a real time clock connected to provide a time stamp to data stored in said non-volatile memory.

7. A system as recited in claim 4, wherein said processor comprises an 8 bit microcontroller with an internal RC oscillator.

8. A system as recited in claim 1, further comprising a regulator, wherein said voltage sensitive switch is connected for providing power to said regulator when said voltage derived from said sensor exceeds said threshold, wherein said regulator is connected to provide a regulated voltage to said processor and to said non-volatile memory.

9. A system as recited in claim 8, further comprising a first energy storage device and a second energy storage device connected to receive energy from said first energy storage device through said switch, wherein said regulator is connected to receive energy from said second energy storage device when said switch is open.

10. A system as recited in claim 9, wherein said first energy storage device includes a first capacitor and wherein said second energy storage device includes a second capacitor.

11. A system as recited in claim 1, wherein said switch includes a bipolar transistor.

12. A system as recited in claim 11, wherein said switch includes a Darlington pair.

13. A system as recited in claim 1, further comprising a voltage divider, wherein said voltage sensitive switch includes a control electrode, wherein said voltage divider is connected to receive said energy from said sensor, wherein said control electrode is connected to said voltage divider to receive a fraction of voltage across said voltage divider.

14. A system as recited in claim 1, further comprising a rectifier connected to rectify a signal from said sensor.

15. A system as recited in claim 14, wherein said rectifier includes a full wave rectifier.

16. A system as recited in claim 1, wherein said non-volatile memory includes at least one from the group consisting of EEPROM, NVRAM, FLASH, FRAM, and low power static RAM, wherein said low power static RAM has battery backup.

17. A system as recited in claim 1, further comprising a second source of power, wherein said non-volatile memory is connected to receive power from said second source of power for communicating data stored in said non-volatile memory.

18. A system as recited in claim 17, wherein said second source of power includes at least one from the group consisting of inductive power and a wired connection to external power.

19. A system as recited in claim 18, wherein said second source of power includes a coil.

20. A system as recited in claim 19, wherein said second source of power includes a magnet in relative motion with said coil.

21. A system as recited in claim 18, wherein said second source of power includes said wired connection, and wherein said wired connection includes at least one from the group consisting of a DC power source, a USB, a CAN bus, and a power over ethernet connector.

22. A system as recited in claim 17, further comprising a diode power multiplexer.

23. A system as recited in claim 1, further comprising a rechargeable energy storage device and a radio transmitter, wherein said rechargeable energy storage device receives all its power derived from said sensor, wherein said radio transmitter is connected to receive power from said rechargeable energy storage device.

24. A system as recited in claim 1, further comprising at least one from the group consisting of a battery and a super capacitor connected for storing energy derived from said sensor.

25. A system as recited in claim 1, wherein said threshold is sufficient to turn on and operate said memory for a sufficient time to record said event.

26. A system comprising a structure and a circuit, said circuit mounted to said structure, said circuit including a sensor, a processor, and a non-volatile memory, wherein said processor and said memory are connected for measuring and recording a single event sensed by said sensor, wherein said sensor generates power during said single event, wherein all power used in said measuring and said recording is derived from said sensor during said single events wherein said circuit includes a switch connected to prevent charge from being transferred to said processor and to said memory until a voltage derived from said sensor exceeds a threshold.

27. A system as recited in claim 26, wherein said structure includes at least one from the group consisting of a vehicle, a building, infrastructure, a weapon, an article of clothing, and a living thing.

28. A system as recited in claim 27, wherein said structure includes said vehicle, and wherein said vehicle includes at least one from the group consisting of an automobile, a truck, a boat, and an aircraft.

29. A system as recited in claim 27, wherein said structure includes said infrastructure, and wherein said infrastructure includes at least one from the group consisting of a bridge, a pipe, a road, and a runway.

30. A system as recited in claim 27, wherein said structure includes said weapon, and wherein said weapon includes at least one from the group consisting of a gun, a rocket, and a missile.

31. A system as recited in claim 27, wherein said structure includes a vehicle, wherein said vehicle includes at least one element from the group consisting of a protective skin and a tile, and wherein said single event includes an impact from a flying object on said element.

32. A system as recited in claim 27, wherein said structure includes a weapon, wherein said weapon includes a gun, and wherein said single event includes an impact from firing of said gun.

33. A system as recited in claim 27, wherein said structure includes a vehicle, wherein said vehicle includes a landing gear, and wherein said single event includes an impact from operation of said landing gear.

34. A system as recited in claim 27, wherein said structure includes a vehicle, wherein said vehicle includes a suspension system, and wherein said single event includes an impact from operation of said suspension system.

35. A system as recited in claim 26, wherein said structure provides energy to said circuit from at least one from the group consisting of vibration, strain, and an impact.

36. A system as recited in claim 26, wherein said non-volatile memory includes FRAM.

37. A system as recited in claim 26, wherein said threshold is sufficient to turn on and operate said processor and said memory for a sufficient time to record said event.

38. A system as recited in claim 26, wherein said structure includes a racquet, and wherein said single event includes an impact on said racquet.

39. A system as recited in claim 26, wherein said structure includes a door, and wherein said single event includes an impact from at least one from the group consisting of opening and closing of said door.

40. A system as recited in claim 26, wherein said structure includes a protective enclosure, and wherein said single event includes an impact from at least one from the group consisting of opening and closing of said protective enclosure.

41. A system comprising a structure and a circuit, said circuit mounted to said structure, said circuit including a sensor, a voltage sensitive switch, a logic circuit, and a memory, wherein said logic circuit and said memory are connected for recording a single event sensed by said sensor, wherein said sensor generates power during said single event, wherein all power used in making said recording is derived from said sensor during said single event, wherein said voltage sensitive switch is connected to prevent charge from being transferred to said logic circuit and to said memory until a voltage derived from said sensor exceeds a threshold.

42. A system as recited in claim 41, wherein said logic circuit includes a digital delay line.

43. A system as recited in claim 41, wherein said threshold is sufficient to turn on and operate said logic circuit and said memory for a sufficient time to measure and record said event.

44. A system comprising a structure and a circuit, said circuit mounted to said structure, said circuit including a sensor, a voltage sensitive switch, a processor, and a memory, wherein said processor and said memory are connected for recording a single event sensed by said sensor, wherein said sensor generates power during said single event, wherein all power used in making said recording is derived from said sensor during said single event, wherein said voltage sensitive switch is connected to prevent charge from being transferred to said processor and to said memory until a voltage derived from said sensor exceeds a threshold.

45. A system as recited in claim 44, wherein said threshold is sufficient to turn on and operate said processor and said memory for a sufficient time to record said event.