The instantaneous normal motion between bodies in a sliding contact is an important variable in determining dynamic friction under unsteady sliding conditions. In order to model friction under dynamic conditions, it is therefore necessary to combine a dynamic model of the sliding system with an accurate model of the friction process. In the present work, the nonlinear normal dynamics of a friction test apparatus are described by a linearized model at a particular steady loading and sliding condition in a mixed or boundary-lubricated regime. The geometry is a line contact. The Hertzian bulk contact compliance and film and asperity damping and stiffness characteristics are included as discrete elements. In Part I of the paper, a fifth-order model is developed for the normal dynamics of the system, using both the Eigensystem Realization Algorithm (ERA) and classical experimental modal analysis techniques. In Part II, this system model is combined with a friction model, developed independently, to describe dynamic friction forces under both harmonic and impulsive applied normal loads.

1.
Armstrong-He´louvry, B., 1991, Control of Machines with Friction, Kluwer Academic Publishers, Boston.
2.
Armstrong-He´louvry, B., Dupont, P., and Canudas de Wit, C., 1994, “A Survey of Models, Analysis Tools and Compensation Methods for the Control of Machines with Friction,” Automatica, in press.
3.
Ewins, D. J., 1984, Modal Testing: Theory and Practice, Research Studies Press Ltd., New York, John Wiley.
4.
Johnson, K. L., 1987, Contact Mechanics, Cambridge University Press, Cambridge.
5.
Johnson
K. L.
,
Greenwood
J. A.
, and
Poon
S. Y.
,
1972
, “
A Simple Theory of Asperity Contact in Elastohydrodynamic Lubrication
,”
Wear
, Vol.
19
, pp.
91
108
.
6.
Juang
J.-N.
, and
Pappa
R. S.
,
1986
, “
Effects of Noise on Modal Parameters Identified by Eigensystem Realization Algorithm
,”
AIAA J. of Guidance, Control and Dynamics
, Vol.
9
, pp.
294
303
.
7.
Juang
J.-N.
,
Cooper
J. E.
, and
Wright
J. R.
,
1988
, “
An Eigensystem Realization Algorithm Using Data Correlations (ERA/DC) for Modal Parameter Identification
,”
J. of Control-Theory and Advanced Technology
, Vol.
4
(
1
), pp.
5
14
.
8.
Mindlin
R. D.
,
1949
, “
Compliance of Elastic Bodies in Contact
,”
ASME Journal of Applied Mechanics
, Vol.
29
, pp.
259
268
.
9.
Polycarpou, A. A., and Soom, A., 1992, “Transitions Between Sticking and Slipping at Lubricated Line Contacts,” Friction-Induced Vibration, Chatter, Squeal, and Chaos, Proc. ASME Winter Annual Meeting, Anaheim, DE-Vol. 49, ASME, New York, pp. 139–148.
10.
Polycarpou, A. A., and Soom, A., 1994a, “Measured Transitions Between Sticking and Slipping at Lubricated Line Contacts,” ASME Journal of Vibrations and Acoustics, in press.
11.
Polycarpou, A. A., and Soom, A., 1994b, “Two-Dimensional Models of Boundary and Mixed Friction at a Line Contact,” ASME JOURNAL OF TRIBOLOGY, in press.
12.
Polycarpou, A. A., and Soom, A., 1994c, “Boundary and Mixed Friction in the Presence of Dynamic Normal Loads; Part II—Friction Transients,” ASME JOURNAL OF TRIBOLOGY, Paper No. 94–Trib–38.
13.
Rohde, S. M., 1980, “A Mixed Friction Model for Dynamically Loaded Contacts With Application to Piston Ring Lubrication,” Surface Roughness Effects in Hydrodynamic and Mixed Lubrication, ASME—The Lubrication Division, pp. 19–50.
14.
Thomson, W. T., 1988, Theory of Vibration with Applications, 3rd Edition, Prentice Hall, Englewood Cliffs, NJ 07632.
15.
Yeh
F. B.
, and
Yang
C.-D.
,
1990
, “
Identification, Reduction, and Refinement of the Model Parameters by the Eigensystem Realization Algorithm
,”
AIAA J. of Guidance, Control and Dynamics
, Vol.
13
(
6
), pp.
1051
1059
.
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