Ce diaporama a bien été signalé.
Nous utilisons votre profil LinkedIn et vos données d’activité pour vous proposer des publicités personnalisées et pertinentes. Vous pouvez changer vos préférences de publicités à tout moment.


224 vues

Publié le

  • Soyez le premier à commenter

  • Soyez le premier à aimer ceci


  1. 1. BioHorizons Fatigue Test System <ul><li>Corp 3 </li></ul><ul><li>Midterm Concepts Presentation </li></ul>
  2. 2. Team Members <ul><li>Jonathan Hill </li></ul><ul><li>John Maddox </li></ul><ul><li>Allen Lindsay </li></ul><ul><li>Crichton Neal </li></ul><ul><li>Chris Howell </li></ul><ul><li>Felicia Craig </li></ul><ul><li>Bradley Johnson </li></ul>
  3. 3. Project Overview <ul><li>General Specification </li></ul><ul><li>ISO Standards </li></ul><ul><li>Primary Concept </li></ul><ul><ul><li>Solid Edge </li></ul></ul><ul><ul><li>Advantages/Disadvantages </li></ul></ul><ul><ul><li>Water Bath </li></ul></ul><ul><ul><li>Economic Analysis </li></ul></ul><ul><li>Secondary Concept </li></ul><ul><li>Phase II </li></ul>
  4. 4. Specifications and Constraints <ul><li>General Constraints </li></ul><ul><ul><li>small and light enough to operate on a tabletop </li></ul></ul><ul><ul><li>clean and quiet enough to operate indoors at the BioHorizons offices </li></ul></ul><ul><ul><li>Able to perform fatigue tests as well as static load tests </li></ul></ul><ul><ul><li>Control system and sensors must measure failure load and cycles to failure and discontinue operation at this point </li></ul></ul><ul><ul><li>Entire system must be able to be calibrated accurately enough for continuous operation within ISO 14801 specifications and constraints </li></ul></ul><ul><li>Economic Constraints </li></ul><ul><ul><li>to produce a fatigue testing machine that can be reproduced and used for less than it currently costs to have the dental implants tested from an outside company </li></ul></ul>
  5. 5. ISO Standards <ul><li>ISO provides more specific specifications and constraints in ISO 14801 —Dentistry—Fatigue test for endosseous dental implants </li></ul><ul><li>Several of the more pertinent specifiations are covered below, obtained from the ISO document: </li></ul><ul><ul><li>The testing machine should be capable of applying the specified load with an error not exceeding ± 5% at maximum load. </li></ul></ul><ul><ul><li>The endosseous dental implant shall be clamped such that it makes a 30° ± 1° angle with the loading direction of the testing machine. </li></ul></ul><ul><ul><li>The device shall clamp the specimen at a distance 3.0 mm ± 0.1 mm apically from the nominal bone level as specified in the manufacturer’s instruction for use. </li></ul></ul>
  6. 6. ISO Standards (continued) <ul><li>More constraints and specifications: </li></ul><ul><ul><li>The dimensions of the loading member shall be chosen to define a distance l = 11.0 mm ± 0.1 mm from the centre of the hemisphere to the clamping plane. </li></ul></ul><ul><ul><li>For endosseous dental implants that include materials in which corrosion fatigue has been reported or is expected to occur…testing shall be carried out in water of Grade 2 according to ISO 3696, in normal saline [.09%]* or in physiologic medium. The fluid and the test specimen shall be kept at 37°C ± 2°C during the testing. </li></ul></ul><ul><ul><li>Fatigue testing shall be carried out with a unidirectional load. The load shall vary sinusoidally between a nominal peak value and 10 % of this value . The loading frequency shall be ≤ 15 Hz . Testing in liquid media shall be conducted at frequencies ≤ 2 Hz . </li></ul></ul>*As specified by BioHorizons
  7. 7. Other Applicable ISO Standards <ul><li>ISO 1099 : Metallic materials—Fatigue testing—Axial force controlled method </li></ul><ul><li>ISO 1942-1 : Dental vocabulary—Part 1: General and clinical terms </li></ul><ul><li>ISO 3696 : Water for analytical laboratory use—Specification and test methods </li></ul><ul><li>ISO 4965 : Axial load fatigue testing machines—Dynamic force calibration—Strain gauge technique </li></ul><ul><li>ISO 7500-1 : Metallic materials—Verification of static uniaxial testing machines—Part 1: Tension/compression testing machines—Verification and calibration of the force- measuring system </li></ul>
  8. 8. Concept Overview
  9. 9. Different Views
  10. 10. Exploded View Temperature Sensor Liquid Bath Container (Pyrex) Washer (Rubber) Container Base Linear Motor/Load Cell Frame (steel) Thumb Screw Insert (will be tapped to hold test piece) Mounting Screws Base (steel) Exploded View
  11. 11. Advantages <ul><li>Long life </li></ul><ul><li>Excellent precision and reliability </li></ul><ul><li>Ease in varying load and frequency </li></ul><ul><li>Low maintenance </li></ul><ul><li>Easy setup </li></ul><ul><li>Small number of parts </li></ul><ul><li>Conduct static and fatigue tests without changing setup </li></ul>
  12. 12. Disadvantages <ul><li>Initial costs are high </li></ul><ul><li>Replacement parts would be high </li></ul><ul><li>Possible motor cooling may need to be addressed </li></ul><ul><li>Different inserts need to be tapped for each implant tested </li></ul>
  13. 13. Water Bath
  14. 14. Major Components <ul><li>Heating element </li></ul><ul><ul><li>Small and compact </li></ul></ul><ul><ul><li>Low fluid volume rated </li></ul></ul><ul><li>Temperature switch </li></ul><ul><ul><li>Small and compact </li></ul></ul><ul><ul><li>+-2 °C tolerance </li></ul></ul><ul><li>Dish </li></ul><ul><ul><li>Metal bottom </li></ul></ul><ul><ul><li>Glass sides </li></ul></ul><ul><ul><li>Water tight </li></ul></ul><ul><li>Water level switch </li></ul><ul><ul><li>Small and compact </li></ul></ul><ul><ul><li>Safely maintain water level </li></ul></ul>
  15. 15. Dish <ul><li>Metal base </li></ul><ul><ul><li>Base for mounting heating components </li></ul></ul><ul><ul><li>Able to drain the dish through a ball valve </li></ul></ul><ul><li>Glass tube </li></ul><ul><ul><li>Forms sides </li></ul></ul><ul><ul><li>Able to withstand high temps incase of heating problems </li></ul></ul><ul><ul><li>Able to see the test specimen during testing </li></ul></ul><ul><li>Washer </li></ul><ul><ul><li>Or sealant as of yet to be determined </li></ul></ul><ul><ul><li>Seals the base to the glass </li></ul></ul>
  16. 16. Standards <ul><li>ISO 14801:2003 </li></ul><ul><ul><li>5.4 Testing Environment </li></ul></ul><ul><ul><ul><li>testing shall be carried out in water of Grade 2 according to ISO 3696 </li></ul></ul></ul><ul><ul><ul><li>fluid and the test specimen shall be kept at 37 °C+2°C or -2 °C </li></ul></ul></ul>
  17. 17. Heating Element <ul><li>Compact Cartridge-Style Immersion Heater </li></ul><ul><ul><li>1 5/8&quot; long type 316 stainless steel element </li></ul></ul><ul><ul><li>Maximum temperature of 100° C </li></ul></ul><ul><ul><li>CSA Certified and UL-Registered </li></ul></ul><ul><ul><li>Can be fully immerged in saline solution </li></ul></ul>
  18. 18. Temperature switch <ul><li>Submersible Cartridge Temperature Switch </li></ul><ul><ul><li>Operates as a thermostat </li></ul></ul><ul><ul><li>300 series stainless steel outer shell </li></ul></ul><ul><ul><li>adjusted between -73° and +315° C </li></ul></ul><ul><ul><li>2” long element </li></ul></ul><ul><ul><li>UL-Registered </li></ul></ul><ul><li>Search continues to refine this component </li></ul>
  19. 19. Water Level Switch <ul><li>Vertical-Mount Liquid-Level Switch </li></ul><ul><ul><li>Maintain a safe water level for the Immersion heating element </li></ul></ul><ul><ul><li>Over all length of 1 7/8“ </li></ul></ul><ul><ul><li>Max temperature rating of 105°C </li></ul></ul><ul><ul><li>When the fluid level drops too low </li></ul></ul><ul><ul><ul><li>cut power to the heating element </li></ul></ul></ul><ul><ul><ul><li>turn on a warning light or trigger a system warning in the testing program letting the tester know to add more fluid </li></ul></ul></ul>
  20. 20. Linear Servo Motor <ul><li>Handles static loading up to 500 lbf. </li></ul><ul><li>Handles a cycling load from 0 to 150 lbf. at a rate up to 15 Hz </li></ul>
  21. 21. Load Cell <ul><li>Piezoelectric sensing cell </li></ul><ul><li>Highly repeatable </li></ul><ul><li>Fatigue Rated load cell </li></ul><ul><li>Low profile to fit easily within machine </li></ul>
  22. 22. Controls <ul><li>Load cell sends a signal through a DAQ card to LabView </li></ul><ul><li>LabView takes the data and depending on the load it will send a signal to the Driver which will in turn increase or decrease the current </li></ul>
  23. 23. Economic Analysis <ul><li>Linear Motor, Cooling Jacket, Controller, and Driver : $19600 </li></ul><ul><li>Load Cell : $1000 </li></ul><ul><li>Lab View : $1200 per year </li></ul><ul><li>Jig Frame and Base : $2000 </li></ul><ul><li>Computer : $600 </li></ul><ul><li>Heating Accessories : $300 </li></ul><ul><li>Cables and Connectors : $200 </li></ul><ul><li>Total Costs : $25000 </li></ul>
  24. 24. Alternative Design
  25. 25. Advantages <ul><li>Cheap saline bath container </li></ul><ul><li>Rotary motor is cheaper than linear motor </li></ul>
  26. 26. Disadvantages <ul><li>Bearings (maintenance) </li></ul><ul><li>Expensive to machine </li></ul><ul><li>Small error in load cell reading due to the bearing friction </li></ul><ul><li>Angle of applied force will be less reliable </li></ul><ul><li>Complicated – many possible places for failure </li></ul>
  27. 27. Phase II-Completed by Dec. <ul><li>Obtain more quotes on linear motors </li></ul><ul><li>Dimension Concept </li></ul><ul><li>Stress Analysis </li></ul><ul><li>Finalize Concept </li></ul>