Friction modeling and identification is a prerequisite for the accurate control of electromechanical systems. This paper considers the identification and control of friction in a high load torque DC motor to the end of achieving accurate tracking. Model-based friction compensation in the feedforward part of the controller is considered. For this purpose, friction model structures ranging from t...

This work presents a nonlinear control algorithm to be applied to the trajectory tracking of a pneumatic positioning system. The objective is to compensate the highly nonlinear effects that are inherent to such systems due to the dynamic behavior of pressurized air inside the chambers and to friction forces. In order to accomplish this task, the proposed algorithm employs the feedback lineariza...

Wearless dry friction of an elastic block of weight N , driven by an external force F over a rigid substrate, is investigated. The slider and substrate surfaces are both microscopically rough, interacting via a repulsive potential that depends on the local overlap. The model reproduces Amontons’s laws which state that the kinetic friction force is proportional to the normal loading force N and ...

Dynamic modelling is an important issue in legged locomotion. However, friction has been neglected in most studied models. The aim of this work is the experimental determination of frictional effects over leg dynamics. For this purpose, previous work on friction modelling in robot manipulators (1), (3), has been followed and similar results have been achieved. However, a new friction component ...

We introduce a method of observer design for systems described by a linear part with a nonlinear perturbation, where the perturbation is parameterized by a vector of unknown, constant parameters. The design is modular, and consists of a modified high-gain observer that estimates the states of the system together with the full perturbation, and a parameter estimator. The parameter estimator is c...

We present a theoretical, numerical, and experimental study about the sliding motion of an angular particle down a vibrated smooth plane. The model is based on a Coulomb's friction law with a unique friction coefficient. The model is solved numerically and is tested with controlled experiments. Different motion regimes are identified and the particle behavior is governed by two dimensionless pa...

Model-based analysis, design and testing methods require precise mathematical process models of high quality. But modelling of systems with friction poses difficult challenges. In this paper, a novel friction-identification method using a sliding-mode observer based friction estimation approach is proposed. This model is used in Hardware-in-the-Loop (HiL) simulation in context of developing mot...

The friction pair of piston rings and cylinder liner is one of the most important friction couplings in an internal combustion engine. It influences engine efficiency and service life. Under the excitation of piston slaps, the dynamic deformation of cylinder liner is close to the surface roughness magnitudes, which can affect the friction and lubrication performance between the piston rings and...

Deep drawing process is one of the most applicable methods in producing industrial parts. In this process, the initial blank deforms to final product using a rigid punch and die. In this investigation, the effect of deep drawing process parameters of brass/steel laminated sheet composites on required forming force has been investigated. The process simulated using finite element method (FEM) an...