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

• US 7,779,708 B2
• Filed: 01/05/2007
• Issued: 08/24/2010
• Est. Priority Date: 01/13/2006
• Status: Active Grant

• Current Assignee: MTS Systems Corporation (Illinois Tool Works Inc.)
• Original Assignee: MTS Systems Corporation (Illinois Tool Works Inc.)
• Inventors: Schulz, Bradley D., Fahrendorff, Harold F.
• Primary Examiner(s): NOLAND, THOMAS
• Application Number:
  US11/649,954
• Publication Number:
  US 20070169573A1
• Time in Patent Office: 1,327 Days
• Field of Search: 738/656, 623/912
• US Class Current: 73/865.6
• CPC Class Codes: A61F 2/44 for the spine, e.g. vertebrae, spinal discs
• CPC Class Codes: A61F 2/468 Testing instruments for artificial joints for testing non-implantable prostheses A61F2/76
• CPC Class Codes: G01N 2203/0021 Torsional
• CPC Class Codes: G01N 2203/0089 Biorheological properties
• CPC Class Codes: G01N 2203/0222 Temperature
• CPC Class Codes: G01N 2203/0242 With circulation of a fluid
• CPC Class Codes: G01N 2203/0246 Special simulation of "in situ" conditions, scale models or dummies
• CPC Class Codes: G01N 2203/0256 Triaxial, i.e. the forces being applied along three normal axes of the specimen
• CPC Class Codes: G01N 3/56 Investigating resistance to wear or abrasion
• CPC Class Codes: Y10S 623/912 Method or apparatus for measuring or testing prosthetic

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.

Claims

1. An orthopedic simulator comprising:

a test station having a specimen container for containing a bath in which a test specimen is immersed during testing; and

a fluid concentration maintenance arrangement operably arranged with the specimen container to maintain a specific fluid concentration of the bath, the fluid concentration maintenance arrangement comprising;

a fluid level sensor positioned to sense the level of fluid in the fluid bath and generate a fluid level signal; and

a fill controller coupled to the fluid level sensor to receive the fluid level signal and arranged to control 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 concentration maintenance arrangement is configured to obtain a value indicative of an initial concentration of the fluid bath 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 1 and comprising:

one or more actuator devices configured to supply one or more test loads to the test specimen immersed in the bath of specimen container.

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; and

a fluid concentration maintenance assembly comprising at least one sensor configured to detect one or more parameters related to a fluid concentration in the bath and a controller configured to receive input from the at least one sensor corresponding to the one or more parameters related to the fluid concentration in the bath.

9. The simulator of claim 8 comprising a fill assembly operably coupled to the controller wherein the controller is configured to operate the fill assembly to supply the bath with replenishing fluid to maintain the fluid concentration of the bath in response to the input from the at least one sensor.

10. The simulator of claim 8, wherein the at least one sensor is a fluid level sensor configured to sense a fluid level of the bath within the specimen container.

11. The simulator of claim 10, further comprising a mounting arrangement that adjustably mounts the fluid level sensor in sensing proximity to the bath.

12. The orthopedic simulator of claim 8 and further comprising a fill assembly to supply fluid to the bath wherein the fill assembly is operably coupled to the controller and the controller is configured to operate the fill assembly based upon the input from the at least one sensor.

13. The simulator of claim 12 wherein the fill assembly comprises at least one pump configured to supply the fluid to the bath and the controller is operably coupled to the pump to supply the fluid to the bath based upon the input from the at least one sensor.

14. The simulator of claim 13 wherein the fill assembly comprises at least one fill tube and the pump supplies the fluid to the bath through the at least one fill tube.

15. The simulator of claim 8 wherein the controller is configured to provide an output indication of the fluid concentration in the bath in response to the input from the at least one sensor.

16. The simulator of claim 15 and comprising at least one pump configured to supply fluid to the bath and the controller is configured to receive an activation input to operate the at least one pump to supply the fluid to the bath.

17. The simulator of claim 8 wherein the simulator comprises:

one or more actuator devices configured to supply one or more test loads to the test specimen immersed in the bath of specimen container.

18. An orthopedic simulator comprising:

one or more actuator devices configured to supply one or more test loads to a test specimen;

a specimen container having a chamber configured to contain a fluid bath in which the test specimen is immersed during testing;

at least one sensor configured to detect one or more parameters related to a fluid concentration of the fluid bath;

a fill assembly configured to supply fluid to the fluid bath; and

a controller operable coupled to the fill assembly and configured to receive and process input from the at least one sensor to control operation of the fill assembly based upon the input from the at least one sensor related to the fluid concentration in the fluid bath.

19. The orthopedic simulator of claim 18 wherein the fill assembly comprises at least one pump configured to provide the fluid to the chamber of the specimen container through at least one inlet to the chamber.

20. The orthopedic simulator of claim 18 wherein the at least one sensor is a non-contact level sensor.