Landing Gear Bearing Test Machine

Project goal: To design, build and test a bearing test machine to determine bearing service life. Journal bearings used in aircraft landing gear absorb radial and axial loads during landing and takeoff. Being non-serviceable and costly to replace, the service life of the bearings must be predictable and adequate for their application. The test machine uses off-the-shelf and fabricated components to move a shaft linearly through a bearing while a radial load of 3,000 pounds is applied. The team used SolidWorks to design the fabricated parts, conducted finite element analysis and motion simulation tests, and followed design for manufacturability practices to produce geometric dimensioning and tolerancing drawings. The linear shaft induces wear of the polytetrafluoroethylene liner, which is measured using a linear variable differential transformer sensor capable of detecting 0.0001 inches of displacement. Signals from the sensors are sent through the data acquisition system and into LabVIEW, which displays and records data. If any information received from the sensors exceeds safety criteria, the machine shuts off and removes load from the test piece. By gathering data on the wear characteristics of bearings smaller than those used in aircraft, it is the sponsor’s goal to create a scalable benchmark that will help establish industry standards regarding bearing service life.