Friction: experimental determination, modeling and compensation

Abstract

The friction behavior of a brush type d.c. servo-motor driven mechanism with gearing is explored. The standard kinetic plus viscous friction model is found t o describe the dominant friction behavior. In addition, a dependence of friction upon position is identified and negative velocity dependence is observed at lolu velocities. A friction model is developed and used t o precompute motion iorques. The application of precomputed torques in an open loop fashion results in motions accurate to within a f e w percent.

Improving the tracking performance of mechanical systems by adaptive extended friction compensation

“…The appearance of periodic or position dependent friction cornponents has been observed proriously and is reported by, e.9., (Armstrong, 1988), but for their system the harmonic friction component was small, in the order of 7Vo of the Coulomb friction. In our case this is not true, so we should explicitly consider puiodic fr iction.…”

Dynamic Parameter Identification for Parallel Manipulators

“…The classical friction model used for identification is a linear model which includes Coulomb and viscous friction. Equation (14) represents a general asymmetrical linear model (Armstrong, 1988) for both Coulomb and viscous friction,…”

Adaptive friction compensation of servo mechanisms

“…It includes a decaying exponential term in the friction model which explains the microscopic limit cycle behavior that, after a breakaway point atẋ, has a negative exponential characterization. Experimental work has shown that this model can approximate real friction forces with a precision of 90% [2,11]. Because of the nonlinearity in unknown parameterẋ s in Tustin's model and the difficulty in dealing with nonlinear parameters, the following simple linear-in-the-parameters (LIP) friction model was proposed [12]:…”