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Abstract
Friction has been studied and analyzed through the years. The need for precise friction measurement has become increasingly important as the need for precision positioning mechanism has increased. This precise control of mechanical systems requires the knowledge of specific parameters in the system. A subset of these parameters is the friction model. Traditionally, friction models are parameterized using steady-state force measurement during sliding contact. In this thesis, a new displacement-based friction measurement machine is designed and constructed, where linear motion is prescribed using a parallelogram leaf-type flexure. The flexure has a natural frequency of 2.24 Hz, a stiffness of approximately 1955 N/m (the average of the two different tests), and a viscous damping ratio of 0.00085. The parasitic motion at a displacement amplitude of 10 mm is less than 0.1 μm and the uncertainty of the relative position of the two samples due to structural deflection is 1 μm.