Orthopedic simulator with fluid concentration maintenance arrangement for controlling fluid concentration of specimen baths

Abstract

An orthopedic simulator is provided with an orthopedic simulator having at least one test station with a specimen container for containing a fluid bath, such as bovine fluid. A fluid level sensor is positioned to sense the level of fluid in the fluid bath and generate a fluid level signal. A fill controller is coupled to the fluid level sensor. The fill controller controls filling of the fluid bath with liquid, such as distilled water, as a function of the fluid level signal to restore and maintain the concentration of the bath.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front, perspective view of an orthopedic simulator in accordance with certain embodiments of the invention, with an external housing removed for illustrative purposes, and with forces being schematically depicted.

FIG. 2 a is a top view of the orthopedic simulator of FIG. 1; FIG. 2b is a front view; FIG. 2c is a bottom view and FIG. 2d is a side view.

FIG. 3 is a view similar to FIG. 1, illustrating the removability of a specimen containment module.

FIG. 4 depicts an exemplary embodiment of an assembled specimen containment module.

FIG. 5 is an exploded view of the specimen containment module of FIG. 4.

FIG. 6 is a side, partially cross-sectional view of the specimen containment module of FIG. 4.

FIG. 7 is a top view of a base of the specimen containment module of FIG. 4.

FIG. 8 is a schematic depiction of an embodiment of a circulation loop for circulating a temperature control fluid in a temperature control circuit.

FIG. 9 depicts two test stations, with one test station having a specimen containment module releasably attached thereto.

FIG. 10 schematically depicts an exemplary arrangement for circulating bath fluid.

FIG. 11 depicts an embodiment of a specimen containment module in an installed position.

FIG. 12 is a perspective view of the orthopedic simulator of FIG. 1, with an indication of the flexion and extension motion.

FIG. 13 is a cross-sectional view of a portion of a flexion/extension motion linkage in accordance with embodiments of the invention.

FIG. 14 is a perspective view of the orthopedic simulator of FIG. 1, with an indication of the lateral bending motion around an axis of rotation.

FIG. 15 is a rear perspective view of the orthopedic simulator of FIG. 1.

FIG. 16 is a perspective view of the orthopedic simulator of FIG. 1, with an indication of anterior/posterior and lateral translation motions.

FIG. 17 depicts a portion of an x-y slide assembly in accordance with embodiments of the present invention.

FIG. 18 is a perspective view of the x-y slide assembly in accordance with embodiments of the present invention.

FIG. 19 is an exploded view of the x-y slide assembly of FIG. 18.

FIG. 20 is a perspective view of the orthopedic simulator of FIG. 1, with an indication of loading in a vertical direction.

FIG. 21 is a perspective view of an embodiment of an actuator in isolation.

FIG. 22 is a top view of the actuator of FIG. 21.

FIG. 23 is a side view of the actuator of FIG. 21.

FIG. 24 is a cross-sectional view of the actuator of FIG. 21.

FIG. 25 is a perspective view of the orthopedic simulator of FIG. 1, with an indication of the axial rotation linkage and a moment provided at a test specimen.

FIG. 26 is a rear perspective view of the orthopedic simulator of FIG. 1, illustrating an embodiment of a central manifold in accordance with embodiments of the present invention.

FIGS. 27-29 schematically depict different approaches to linkages.

FIG. 30 schematically depicts a nesting order of forces in accordance with embodiments of the present invention.

FIG. 31 shows the required forces for application to a test specimen intended for a lumbar region according to an exemplary set of curves.

FIG. 32 shows the same information as FIG. 31, but for cervical data.

FIG. 33 shows curves for non-sinusoidal input data in accordance with exemplary embodiments of the invention.

FIG. 34 depicts the orthopedic simulator within a housing.

Claims

1. An orthopedic simulator having at least one test station with a specimen container for containing a fluid bath, comprising: a fluid level sensor positioned to sense the level of fluid in the fluid bath and generate a fluid level signal; anda fill controller coupled to the fluid level sensor that controls filling of the fluid bath with replenishing fluid as a function of the fluid level signal.

2. The simulator of claim 1, wherein the fluid level sensor is a non-contact level sensor.

3. The simulator of claim 2, further comprising a fill tube positioned to provide the replenishing fluid to the fluid bath as controlled by the fill controller.

4. The simulator of claim 3, further comprising a mounting element, the fluid level sensor being adjustably mounted on the mounting element in sensing proximity to the fluid bath.

5. The simulator of claim 4, wherein the mounting element is a vertically extending rod and the fluid level sensor is adjustable vertically along the rod.

6. The simulator of claim 5, wherein the fluid bath has an initial concentration and the fill controller is configured to control filling of the fluid bath so as to maintain the initial concentration.

7. The simulator of claim 6, wherein the replenishing fluid is water.

8. An orthopedic simulator comprising: a test station having a specimen container for containing a bath in which a test specimen is immersed during testing; anda fluid concentration maintenance arrangement in fluid communication with the specimen container to maintain a specific fluid concentration of the bath.

9. The simulator of claim 8, wherein the fluid concentration maintenance arrangement includes a fill controller that controls re-filling the specimen container with replenishing fluid to maintain the fluid concentration of the bath.

10. The simulator of claim 9, wherein the fluid concentration maintenance arrangement further includes a sensor, coupled to the fill controller, which senses a parameter of the bath functionally related to the fluid concentration of the bath.

11. The simulator of claim 10, wherein the sensor is a fluid level sensor that senses the level of the bath within the specimen container.

12. The simulator of claim 11, wherein the fluid level sensor is a non-contact level sensor.

13. The simulator of claim 12, wherein the replenishing fluid is distilled water.

14. The simulator of claim 13, further comprising a mounting arrangement that adjustably mounts the fluid level sensor in sensing proximity to the bath.

15. The simulator of claim 13, wherein the bath comprises bovine fluid.

16. A method of maintaining a fluid concentration of a specimen bath in an orthopedic simulator, comprising the steps of: determining an initial concentration of the specimen bath;monitoring at least one parameter of the specimen bath related to the fluid concentration of the specimen bath; andadjusting the fluid concentration in the specimen bath to the initial concentration in response to the monitoring of the at least one parameter.

17. The method of claim 16, wherein the at least one parameter is a fluid level of the specimen bath and the step of monitoring includes determining the fluid level of the specimen bath.

18. The method of claim 17, wherein the step of determining the fluid level of the specimen bath includes sensing the fluid level of the bath with a non-contact level sensor.

19. The method of claim 18, wherein the step of adjusting includes re-filling the specimen bath with distilled water in response to signals from the non-contact level sensor until the initial concentration of the specimen bath is reached.

20. The method of claim 17, further comprising the step of triggering settable indicators based on the determined fluid level of the specimen bath.

21. The method of claim 20, further comprising the step of generating an indicator of the determined fluid level.

22. The method of claim 21, further comprising activating at least one switch in response to the generated indicator to provide replenishing fluid to the specimen bath until the specimen bath is re-filled.

23. An orthopedic simulator comprising: a test station having a specimen container for containing a bath in which a test specimen is immersed during testing; anda fluid concentration maintenance arrangement in fluid communication with the specimen container to maintain a specific fluid concentration of the bath, the fluid concentration maintenance arrangement including a controller with settable indicators that cause an indication of a low fluid level of the bath, and a re-filling system operable by an operator in response to the indication to re-fill the specimen container with replenishing fluid.

24. The simulator of claim 24, wherein the fluid concentration maintenance arrangement includes a fluid level sensor that senses the level of the bath within the specimen container.

25. The simulator of claim 25, wherein the fluid concentration maintenance arrangement includes a semi-automatic refilling system actuable by a human to cause replenishing fluid to re-fill a specified specimen container through tubing.