= David G. Lewicki
{c}
<David G. Lewicki> is a researcher whose documented work addresses <gear> dynamics, durability and vibration-based detection of tooth damage. His1986 NASA technical paper, <Predicted Effect of Dynamic Load on Pitting Fatigue Life for Low-Contact-Ratio Spur Gears by David G. Lewicki>, studied how dynamically varying tooth loads change predicted <gear surface pitting> fatigue life. Its parametric calculations showed why a static transmitted-load estimate alone can miss important speed-dependent effects.<Predicted Effect of Dynamic Load on Pitting Fatigue Life for Low-Contact-Ratio Spur Gears by David G. Lewicki>[NASA Technical Paper2610, title page; Summary, printed p.1; Summary of Results, printed p.11]{ref}
The scientific distinction is between the mean transmitted <torque> and the changing tooth-contact <force>. Even at the same mean <torque>, a mesh can have different peak loads as operating speed approaches a structural <natural frequency>. The1986 study linked these changing dynamic loads to life predictions for low-<gear contact ratio> <spur gears>; it was a model-based investigation, rather than a universal measured life law.
Lewicki later coauthored a2015 study with <Nicholas A. Lambert> and <Robert S. Wagoner> comparing <rotating accelerometers> on a helicopter-transmission pinion with stationary housing sensors. That experimental work connects the dynamic-load problem to the practical question of which <gear vibration spectrum> features reveal damage. The1986 title page gives his affiliation as the Propulsion Directorate at Lewis Research Center; the2015 report lists Glenn Research Center.<Evaluation of MEMS-Based Wireless Accelerometer Sensors in Detecting Gear Tooth Faults in Helicopter Transmissions by David G. Lewicki and others>[Title page and printed p.1, author affiliations and experimental objective]{ref}
Back to article page
