System for continuous wave, pulsed, and pulsed-echo parameter measurement

• US 8,424,384 B2
• Filed: 06/29/2010
• Issued: 04/23/2013
• Est. Priority Date: 06/30/2009
• Status: Expired due to Fees

• Current Assignee: OrthoSensor, Inc (Stryker Corporation)
• Original Assignee: OrthoSensor, Inc (Stryker Corporation)
• Inventors: Stein, Marc, Kelly, Andrew
• Primary Examiner(s): SAINT SURIN, JACQUES M
• Application Number:
  US12/826,247
• Publication Number:
  US 20100331687A1
• Time in Patent Office: 1,029 Days
• Field of Search: 735/79, 735/97, 736/02, 600/439
• US Class Current: 73/579
• CPC Class Codes: A61B 5/4509 Bone density determination
• CPC Class Codes: A61B 5/4528 Joints A61B5/4533, A61B5/4538 take precedence
• CPC Class Codes: A61B 5/6846 specially adapted to be brought in contact with an internal body part, i.e. invasive
• CPC Class Codes: A61B 5/6878 Bone
• CPC Class Codes: A61B 5/7239 using differentiation including higher order derivatives
• CPC Class Codes: A61B 8/15 Transmission-tomography

Abstract

A measurement system for capturing a transit time, phase, or frequency of energy waves propagating through a propagation medium is disclosed. The measurement system comprises two different closed-loop feedback paths. The first path includes a driver circuit (628), a transducer (604), a propagation medium (602), a transducer (606), and a zero-crossing receiver (640). The zero-crossing receiver (640) detects transition states of propagated energy waves in the propagation medium including the transition of each energy wave through a mid-point of a symmetrical or cyclical waveform. A second path includes the driver circuit (1228), a transducer (1204), a propagation medium (1202), a reflecting surface (1206), and an edge-detect receiver (1240). Energy waves in the propagating medium (1202) are reflected at least once. The edge-detect receiver (1240) detects a wave front of an energy wave. Each positive closed-loop path maintains the emission, propagation, and detection of energy waves in the propagation medium.

Claims

1. A measurement system comprising:

a propagation medium;

a propagation tuned oscillator (PTO) coupled to the medium where the PTO facilitates a continued emission, propagation, and detection of one or more energy waves through the propagation medium and where the PTO is configured to select one of continuous wave, pulsed, and pulsed echo modes of operation where the propagation tuned oscillator further comprises;

a first multiplexer having a first terminal, a second terminal, third terminal and a fourth terminal;

a second multiplexer having a first terminal, a second terminal, a third terminal, and a fourth terminal;

a third multiplexer having a first terminal, a second terminal, a third terminal, and a fourth terminal

a driver circuit having an input coupled to the fourth terminal of the first multiplexer and an output coupled to the first terminal of second multiplexer and the first terminal of the third multiplexer where the output of the driver circuit is configured to couple to a first location of the propagation medium;

a zero-crossing receiver having an input coupled to the second terminal of the second multiplexer and the second terminal of the third multiplexer and an output coupled to the second terminal of the first multiplexer where the input of the zero crossing receiver is configured to couple to a second location of the propagation medium and where the output of the zero-crossing receiver is configured to couple to the input of the driver circuit to form a positive closed-loop feedback path.

2. The system of claim 1 further including an edge detect receiver having an input coupled to a third terminal of the second multiplexer and a third terminal of the third multiplexer and the edge detect receiver having an output coupled to the second terminal of the first multiplexer.

3. The system of claim 2 further including:

a first transducer coupled to the propagation medium at the first location where the first transducer has a terminal coupled to the fourth terminal of the second multiplexer; and

a second transducer coupled to the propagation medium at the second location where the second transducer has a terminal coupled to fourth third terminal of the third multiplexer.

4. The system of claim 3 further including an oscillator having an output coupled to the third terminal of the first multiplexer configured to initiate energy wave propagation where the oscillator is configured to couple to the first location of the propagation medium and where the oscillator is decoupled from the propagation medium upon detection of a propagated energy wave.

5. The system of claim 4 where a continuous wave energy wave or a pulsed energy wave propagates through the propagation medium when the zero-crossing receiver is configured in the positive closed-loop feedback path.

6. The system of claim 1 further including

an edge-detect receiver having an input coupled to a third terminal of the second multiplexer and a third terminal of the third multiplexer and the edge-detect receiver having an output coupled to the second terminal of the first multiplexer.

7. The system of claim 6 further including:

a first transducer coupled to the propagation medium at the first location where the first transducer includes a terminal coupled to the fourth output of the second multiplexer; and

a reflecting surface coupled to the propagation medium at the second location where the reflecting surface is configured to reflects energy waves back to the first location.

8. The system of claim 7 where the measurement system is configured to couple the reflected energy wave to the edge-detect receiver or the zero-crossing receiver.

9. The system of claim 1 further including an oscillator having an output coupled to a fourth terminal of the first multiplexer configured to initiate energy wave propagation where the oscillator is configured to couple to the first location of the propagation medium and where the oscillator is decoupled from the propagation medium upon detection of a propagated energy wave.

10. The system of claim 1 where the measurement system includes the capture of parameters including, but not limited to, transit time, phase, or frequency of the energy waves propagating through the medium.

11. A measurement system comprising:

a first selectable positive closed-loop feedback path comprising;

a driver circuit to enable emission of one or more energy waves into a medium;

a zero-crossing receiver coupled to the medium to detect a propagated energy wave;

a second selectable positive closed-loop feedback path comprising;

the driver circuit to enable emission of one or more energy wave into the medium; and

an edge-detect receiver coupled to the medium to detect a propagated energy wave where the measurement system is configured such that the zero-crossing receiver or the edge-detect receiver are not simultaneously in the positive close-loop feedback path.

12. The measurement system of claim 11 where the system captures parameters including, but not limited to, transit time, phase, or frequency of the energy waves.

13. The system of claim 11 where the zero-crossing receiver is configured to detects transition states of propagated energy waves in the medium including the transition of each energy wave through a mid-point of a symmetrical or cyclical waveform.

14. The system of claim 13 where the zero-crossing receiver is configured to detect a continuous energy wave or a pulsed energy wave coupled from the medium.

15. The system of claim 11 where the edge-detect receiver is configured to detects wave fronts of pulsed energy waves propagating in the medium while disregarding secondary waves of each pulsed energy wave.

16. The system of claim 15 where the edge-detect receiver is configured to detect a reflected pulsed energy wave.

17. A measurement system comprising:

a zero-crossing receiver having an input and an output;

an edge-detect receiver having an input and an output;

a first multiplexer having a first terminal coupled to the output of the zero-crossing receiver, a second terminal coupled to the output of the edge-detect receiver, a third terminal, and a fourth terminal;

a driver circuit having an input coupled to the fourth terminal of the first multiplexer and an output;

a second multiplexer having a first terminal coupled to the output of the driver circuit, a second terminal coupled to the input of the edge-detect receiver, and a third terminal; and

a third multiplexer having a first terminal and a second terminal coupled to the input of zero-crossing receiver.

18. The measurement system of claim 17 further including:

a propagation medium;

a first transducer coupled to the propagation medium at a first location; and

a second transducer coupled to the propagation medium at a second location where the first multiplexer is enabled to couple the output of the zero-crossing receiver to the input of the driver circuit, where the second multiplexer is enabled to couple the output of the driver circuit to a terminal of the first transducer, and where the third multiplexer is enabled to couple a terminal of the second transducer to the input of the zero-crossing receiver thereby forming a positive closed-loop feedback path that sustains the emission, propagation, and detection of energy waves in the propagation medium.

19. The measurement system of claim 17 further including:

a propagation medium;

a transducer coupled to the propagation medium at a first location; and

a reflecting surface coupled to the propagation medium at a second location where the first multiplexer is enabled to couple the output of the edge-detect receiver to the input of the driver circuit, where the second multiplexer is enabled to couple the output of the driver circuit to a terminal of the transducer to emit an energy wave into the propagation medium, and where the second multiplexer is enabled to couple the terminal of the transducer to the input of the edge-detect receiver to detect a reflected energy wave thereby forming a positive closed-loop feedback path that sustains the emission, propagation, and detection of energy waves in the propagation medium.

20. The measurement system of claim 17 further including an oscillator having an output coupled to third terminal of the first multiplexer where the first multiplexer is enabled to couple the output of the oscillator to the input of the driver circuit to initiate a measurement sequence and where the measurement system includes the capture of parameters including, but not limited to, transit time, phase, or frequency of the energy waves propagating through the propagation medium.