ANALYSIS (Note: Record your answers on the DATA SHEET provided at the end of this lab document) 1. Watch this example VIDEO of a fatigue test being conducted on a prosthetic foot. (https://www.youtube.com/watch?v=M5rsQXKCXIO) 2. Using the equation below, calculate the modified endurance limit (S) of the aluminum pins. Sn = Sn Cst Cm CrCs C 3. Calculate the stress concentration factor (K) for the shouldered pins. 4. What are the measured stresses (omeo) corresponding to the strains from Table 1 above? 5. What are the maximum stresses (max) corresponding to the measured stresses (mea) from question 3 and stress concentration factor K+ from question 2? 6. Using the fatigue formula (S=S,*N") with the modified endurance limit S, from question 2, and the maximum Stresses (max) from question 5, what are the theoretical cycles N? 7. Calculate the percent error between the cycles to failure Nf and the theoretical cycles Nt. 2. Modified endurance limit (S.) of the aluminum pins 3. Stress concentration factor (K) for the shouldered pins Fill in the Table below: # Strain & Cycles to Measured Maximum failure Nf stress mea stress Omax 1 133.3e-6 1,264,339 2 13.3e-6 978,451 3 113.1e-6 4,531,785 4 113.1e-6 5,780,041 56 5 96.e-6 23,093,185 6 96.e-6 28,265,540 U Theoretical Error % cycles Nt