Force monitoring system

• US 20070234819A1
• Filed: 03/29/2006
• Published: 10/11/2007
• Est. Priority Date: 03/29/2006
• Status: Active Grant

• Current Assignee: Orthos Sensing Technologies
• Original Assignee: Orthos Sensing Technologies
• Inventors: Amirouche, Farid, Lopez Espina, Carlos
• Granted Patent: US 8,141,437 B2
• Time in Patent Office: Days
• US Class Current: 73/781
• CPC Class Codes: A61F 2/389 Tibial components A61F2/3868 takes precedence
• CPC Class Codes: A61F 2/4657 Measuring instruments used for implanting artificial joints for surgical instruments A61B90/06
• CPC Class Codes: A61F 2/4684 Trial or dummy prostheses
• CPC Class Codes: A61F 2002/30668 Means for transferring electromagnetic energy to implants
• CPC Class Codes: A61F 2002/4666 for measuring force, pressure or mechanical tension
• CPC Class Codes: G01L 1/2225 the direction being perpendicular to the central axis
• CPC Class Codes: G01L 5/0019 by using strain gages, piezoelectric, piezo-resistive or other ohmic-resistance based sensors

Abstract

A system monitors dynamic forces between bearing surfaces. Based on sensed data, the system may model the forces on the bearing surfaces, analyze these forces, store data relating to these forces, and/or transmit data to an external data gathering device. The system includes a first body piece and a second body piece which mate together. The first and second body pieces comprise bearing surfaces that contact a material that may exert a force. A protrusion, such as a pole, post, or beam, extends from first body piece'"'"'s bearing surface. At least one sensor is disposed on a pole. The at least one sensor detects a mechanical motion of the pole resulting from a force imposed on the body pieces, and generates data indicative of this force. A computer communicates with the at least one sensor and processes the sensed and/or modeled data.

Claims

1. A system that monitors forces between bearing surfaces, comprising:

a first body piece comprising a pole extending relative to an inside surface of a bearing surface;

at least one sensor disposed on the pole;

a second assembly configured to receive the pole of the first body piece such that the first body piece and second body piece mate together and move relative to one another, the computer enclosed within the mated body pieces; and

a computer in communication with the at least one sensor and disposed between the first body piece and the second body piece when they mate together;

where the at least one sensor is configured to detect a mechanical motion of the pole in response to a force on an external surface of the second body piece.

2. The system of claim 1, further comprising conditioning logic in communication with the at least one sensor and the computer.

3. The system of claim 2, where the conditioning logic is flexibly coupled to the at least one sensor.

4. The system of claim 3, where the at least one sensor is further configured to detect a mechanical motion of the pole in response to a force on an external surface of the first assembly.

5. The system of claim 4, where the detection of the mechanical motion occurs in real-time.

6. The system of claim 5, where the at least one sensor transmits a voltage signal in response to the mechanical motion of the pole.

7. The system of claim 6, where the signal conditioning logic converts the voltage signal to an electrical signal related to an amount of deformation in the pole.

8. The system of claim 7, where the signal conditioning logic substantially removes a continuous noise from the electrical signal.

9. The system of claim 7, where the signal conditioning logic amplifies the electrical signal.

10. The system of claim 9, where the computer is configured to transmit at least a portion of the amplified signal through a wired medium.

11. The system of claim 9, where the computer is configured to transmit at least a portion of the amplified signal through a wireless medium.

12. The system of claim 9, where the computer generates a data modeling the mechanical motion of the pole.

13. The system of claim 12, where a memory stores the modeled data.

14. The system of claim 13, where the computer transmits at least a portion of the modeled data through a wired medium.

15. The system of claim 13, where the computer transmits at least a portion of the modeled data through a wireless medium.

16. The system of claim 15, where the computer transmits at least a portion of the modeled data in real-time.

17. A method of monitoring a force between bearing surfaces, comprising:

embedding inside a weight bearing structure a monitoring device comprising a first body piece and a second body piece, a pole extending relative to the first body piece and received by the second body piece;

detecting a mechanical motion of the pole relating to a force imposed on the monitoring device by the weight bearing structure;

conditioning the detected data;

processing the conditioned data; and

transmitting the processed data.

18. The method of claim 17, where the act of detecting a mechanical motion of the pole comprises affixing at least one sensor to the pole.

19. The method of claim 18, where the act of detecting a mechanical motion of the pole further comprises generating a voltage signal representative of a sensed mechanical motion.

20. The method of claim 19, where the act of conditioning the detected data comprises converting the voltage signal to a data representative of an amount of force exerted by the weight bearing surface.

21. The system of claim 20, where the act of processing the conditioned data comprises performing a statistical analysis on the data representative of the amount of force exerted by the weight bearing surface.

22. The method of claim 21, where the act of transmitting the processed data comprises establishing a wireless connection with a data gathering device.

23. The method of claim 22, where the act of transmitting the processed data further comprises transmitting the processed data in real-time.

24. A system that monitors forces between bearing surfaces, comprising:

an enclosure comprising a force bearing surface;

at least two sensors oriented in different planes and disposed such that they extend at an angle from the force bearing surface;

and a computer in communication with the at least two sensors;

where the computer is disposed within the enclosure.

25. The system of claim 24, where the at least two sensors are disposed at an angle of 90 degrees with respect to the force bearing surface.

26. The system of claim 25, where the at least two sensors are configured to measure at least one of an axial or bending strain.

27. The system of claim 24, where the at least two sensors are disposed at an angle of ±

45 degrees with respect to the force bearing surface.

28. The system of claim 27, where the at least two sensors are configured to measure at least one of an axial, bending, shear, or torsional strain.

29. A system that monitors forces between bearing surfaces, comprising:

means for detecting data relating to a force imposed on a structure embedded within a weight bearing structure;

processing means for processing the detected data; and

means for transmitting the processed data to a data gathering device.

30. A system that monitors forces between bearing surfaces, comprising:

an enclosure comprising a force bearing surface;

at least one sensor disposed such that it extends at an angle from the force bearing surface;

and a computer in communication with the at least one sensor;

where the at least one sensor measures according to beam theory a dynamic force imposed on the weight bearing surfaces, and

where the computer is disposed within the enclosure.

31. The system of claim 30, where the dynamic force is used to determine a force component of at least one of a stress or strain along an X-axis, Y-axis, or Z-axis of the enclosure.