1 / 17

Failure and Design

Failure and Design. Jaime Baber October 12, 2000 BME 272: Dr. Paul H. King. Introduction. Failure: Degradation of performance of a device outside of a specified value Non Performance or inability to perform for a certain time within space conditions Causes of Failure: Systemic and Random

kioko
Download Presentation

Failure and Design

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Failure and Design Jaime Baber October 12, 2000 BME 272: Dr. Paul H. King

  2. Introduction • Failure: Degradation of performance of a device outside of a specified value • Non Performance or inability to perform for a certain time within space conditions • Causes of Failure: Systemic and Random • Diabetes Test Kit

  3. Similar Terms • Defect : An imperfection (which may/may not lead to failure) • Deficiency: Lack of conformance to specifications • Malfunction: Unsatisfactory performance • Fault: Cause of failure • Could be something in environment • Something that happens to device: not internal

  4. Failure is a fact of life...

  5. Failure is a fact of life... • Define operational issues/normal operation • Failure rate • Anticipate the worst • Failure Mode Analysis • Design around it: FAIL SAFE

  6. Hardware Failure • Early: First 1,000 hours • Random: Mid-life • Wearout: Late • Artificial Hip

  7. Software Failure • Specification errors • Design Error • Typo • Ommission • Lack of Verification

  8. Human Error….

  9. Human Error • Most important • Documentation: Not up-to-date or missing • Engineers must review and test • Track Failures

  10. Reliability • Describes how dependable a device is over time • Performs for a stated environment/time w/o failure • Plan/Design/Manufacture reliability into product • vs Quality

  11. Mechanical Reliability • Due to deterioration of design strength or assembly

  12. Electronic Reliability • Three distinct time periods

  13. Software Reliability

  14. Overall Device Reliability

  15. Reliabilty Assurance • Design Fault Tolerance • Improve Manufacturing • Quality Assurance Teams/ Inspect • Service Manuals • Test • Monitor

  16. Design….

  17. designsafe... • Task Based Safety Analysis • Hazard Analysis • Users • Tasks • Risk Assessment • Four levels of severity

More Related