Reliability Analysis of a Ti-35II Calculator

Rensselaer Polytechnic InstituteDepartment of Engineering and Science

DSES-6070 HV6 Statistical Methods for Reliability Engineering

Term Project

Curtis Heath RieweAugust 11, 2008

Problem Description

• Analytically determine the reliability of a Texas Instruments Ti-35II calculator

• Determine mean time to failure (MTBF)

• Determine number of calculators that fail in the first month per million sold for warrantee issues

• Determine the which component that has the most impact on reliability

Methodology

• Tear down calculator to construct bill-of-materials

• Determine reliability of each component using Lambda Predict 2– Specification MIL-217

• Calculate the reliability of the system Rs using a series model

• Calculate the failure probability, Fs.• Calculate the Birnbaums Numbers for the

system

Results• 99,520 hours Mean Time Between Failures• 7330 Units can be expected to fail within the 30 day warrantee

period per million sold. • 84503 Units can be expected to fail within one year of purchase per

million sold.• The switch has the most significant affect on reliability of the

calculator