MEMS sensor enabled RFID system and method for operating the same

• US 8,618,914 B2
• Filed: 01/04/2011
• Issued: 12/31/2013
• Est. Priority Date: 01/05/2010
• Status: Active Grant

• Current Assignee: Regents of the University of California (University of California)
• Original Assignee: Regents of the University of California (University of California)
• Inventors: Bachman, Mark, Zhang, Yang, McLaughlin, Scott
• Primary Examiner(s): Lim, Steven
• Assistant Examiner(s): Alizada, Omeed
• Application Number:
  US12/984,451
• Publication Number:
  US 20110163850A1
• Time in Patent Office: 1,092 Days
• Field of Search: None
• US Class Current: 340/10.1
• CPC Class Codes: G06K 19/0702 the arrangement including a battery
• CPC Class Codes: G06K 19/0717 the sensor being capable of sensing environmental conditions such as temperature history or pressure
• CPC Class Codes: G06K 19/07749 the record carrier being capable of non-contact communication, e.g. constructional details of the antenna of a non-contact smart card

Abstract

An apparatus provides environmental monitoring of an item and includes an RFID tag, and a passive switch for sensing an environmental parameter to which the item is subjected, and coupled to the RFID tag so that a measurement of the sensed environmental parameter can be stored, the RFID tag for providing remote readout of the sensed environmental parameter. A method provides environmental monitoring of an item and includes the steps of sensing an environmental parameter to which the item is subjected with activation of a passive switch, storing a measurement of the sensed environmental parameter upon the event of activation of the passive switch, and providing remote readout of the measurement of the sensed environmental parameter with an RFID tag.

Claims

1. An apparatus for providing environmental monitoring of an item comprising:

an RFID tag;

a switch for sensing an environmental parameter to which the item is subjected, and coupled to the RFID tag so that a measurement of the sensed environmental parameter can be stored, the RFID tag for providing remote readout of the sensed environmental parameter;

a microprocessor configured to determine if the sensed environmental parameter has exceeded a pre-determined threshold or if the sensed environmental parameter has changed since a previous measurement; and

a memory element coupled to the switch to store the sensed environmental parameter if and only if the sensed environmental parameter has exceeded the pre-determined threshold or has changed since a previous measurement; and

a battery coupled to the switch,

where the RFID tag, microprocessor and memory element are coupled to the battery through the switch, power being drawn from the battery to the RFID tag and microprocessor only when the environmental parameter has been sensed, or to the RFID tag, microprocessor and memory element only when the environmental parameter is stored in the memory element when the sensed environmental parameter has exceeded the pre-determined threshold or if the sensed environmental parameter has changed since the previous measurement,

whereby remote readout of the measurement of the sensed environmental parameter with the RFID tag provides an environmental history of individual, perishable items over a prolonged time during transportation and distribution.

2. The apparatus of claim 1 where the switch senses temperature, pressure, humidity, or acceleration.

3. The apparatus of claim 1 further comprising a switch in which the cantilever indicates whether a threshold value of the sensed environmental parameter has been reached or exceeded.

4. The apparatus of claim 1 where the switch comprises a MEMS bi-material cantilever and where the sensed environmental parameter is temperature.

5. The apparatus of claim 3 where the threshold value of the sensed environmental parameter is a maximum permitted temperature.

6. The apparatus of claim 3 where the threshold value of the sensed environmental parameter is a minimum permitted temperature.

7. The apparatus of claim 1 further comprising a plurality of switches for sensing a corresponding plurality of environmental parameters to which the item is subjected, the plurality of switches being coupled to the RFID tag for recordal of the plurality of environmental parameters and to provide remote readout of the sensed plurality of environmental parameters,

where the RFID tag, microprocessor and memory element are coupled to the battery through each of the plurality of switches, power being drawn from the battery only when the microprocessor senses that the predetermined threshold has been exceeded or the sensed environmental parameter has changed since a previous measurement.

8. The apparatus of claim 1 further comprising a flexible printed circuit board on which the RFID tag and switch are mounted, the switch being fabricated directly on the flexible printed circuit board for temperature, humidity, acceleration or orientation sensing.

9. The apparatus of claim 7 where the plurality of switches are arranged and configured to sense whether a temperature range has been maintained at all times for the monitored item.

10. The apparatus of claim 7 where the tag is arranged and configured to provide a readout if any past event characterized by at least one of a plurality of sensed environmental parameters signified that a predefined environmental condition has been exceeded.

16. The apparatus of claim 1 where the switch is integrated directly into the RFID tag.

18. The apparatus of claim 1 further comprising a high resolution active sensors of an environmental parameter coupled to the RFID tag and activated by the switch.

11. A method for providing environmental monitoring of an item comprising:

sensing an environmental parameter to which the item is subjected with activation of a passive switch;

determining if the sensed environmental parameter has exceeded a pre-determined threshold or if the sensed environmental parameter has changed since a previous measurement using an a data processing circuit therefor;

storing a measurement of the sensed environmental parameter in a memory element upon the event of activation of the switch if and only if the sensed environmental parameter has exceeded the pre-determined threshold or has changed since a previous measurement as determined by the data processing circuit; and

providing remote readout of the measurement of the sensed environmental parameter with an RFID tag; and

providing power from a thin-film battery to the data processing circuit and RFID tag through the switch only when the environmental parameter has been sensed, or to the data processing circuit, memory element and RFID tag through the switch the only when the environmental parameter is stored in the memory element when the sensed environmental parameter has exceeded the pre-determined threshold or if the sensed environmental parameter has changed since the previous measurement, so that an environmental history of individual, perishable items over a prolonged time during transportation and distribution is provided.

12. The method of claim 11 where the item is a biological or medical item and further comprising storing information in the RFID tag specifically relating to the biological or medical item to provide the information combined with stored sensed environmental parameters to which the item has been subject for inventory monitoring or distribution of blood, organs and biological materials.

13. The method of claim 11 where the environmental history is stored and further comprising adjusting the rate at which the environmental parameter is sensed and stored in real time to save energy consumption.

14. The method of claim 11 further comprising rejecting any item experiencing a hostile environment for an extended period of time through an RFID screening conducted by a recipient of the item.

15. The method of claim 11 further comprising:

sensing a plurality of environmental parameters to which the item is subjected with selective activation of at least one of a corresponding plurality of switches;

storing a corresponding plurality of measurements of the sensed environmental parameters in a memory element upon activation of at least one of a corresponding plurality of switches;

providing remote readout of the plurality of measurements of the sensed environmental parameters with an RFID tag, where the plurality of switches are arranged and configured to sense whether a predetermined environmental parametric range has been maintained at all times for the monitored item as determined by the data processing circuit; and

providing power to the data processing circuit, the memory element and the RFID tag from a thin-film battery through each of the switches only on activation of the switch.

17. The apparatus of claim 15 where the switch is integrated into a flexible PCB with the RFID tag.