An experimental implementation of an output-feedback controller on a rotor dynamic system with set-valued friction is presented. The system exhibits coexisting stable/unstable equilibria and undesired friction-induced limit cycles. In the system, the friction and actuation are non-collocated, which prevents the application of standard friction compensation techniques. Therefore, an outputfeedba...

This paper presents a comparative study among friction behavior of several double-acting pneumatic actuators available to industrial use. A brief review covering the manner that pneumatic actuator manufacturers and current literature approach friction force and its usual models also is presented. After depicting friction test methodology and test apparatus, the comparison work is carried out th...

Friction accounts for more than 60% of the motor torque, and hard nonlinearities due to Coulomb friction and stiction severely degrade control performances as they account for nearly 30% of the industrial robot motor torque. Although many friction compensation methods are available (Armstrong-Helouvry et al., 1994; Lischinsky et al., 1999; Bona & Indri, 2005;), here we only introduce relatively...

Friction is an undesired phenomenon in many drive systems. Feedforward of a suitable estimate of friction is an effective method to compensate the friction-dependent position errors in the steady state. The speed of reconstruction of the real friction is crucial for the grade of improvements which can be achieved for the transient behaviour. A nonlinear model-based approach is presented in this...

In this article, an intelligent compensation control algorithm for low-speed robot joint with dynamic friction was proposed based on self-recurrent wavelet neural networks (SRWNN). It is not necessary to predict the dynamic model parameters, and the high-precision compensation of nonlinear friction is realized by using few neurons and iterations through only position feedback. Lyapunov stabilit...

A new nonlinear disturbance observer (NDO) for robotic manipulators is derived in this paper. The global exponential stability of the proposed disturbance observer (DO) is guaranteed by selecting design parameters, which depend on the maximum velocity and physical parameters of robotic manipulators. This new observer overcomes the disadvantages of existing DO’s, which are designed or analyzed b...

We present a new method of neural friction compensa tion in manipulator control especially during dynamic tasks with de ned contact to external environment Such manipulator movements involve internal joint friction and external friction between tool and environment The suggested method compensates friction caused dis turbances by means of neural networks Based on a minimal friction model Lyapun...

For control applications aiming accurate positioning and path tracking friction modelling and compensation can be very important, especially when working with small displacements as usual in nano technologies. The paper at hand describes friction identification and friction model application for a linear high-precision ball bearing guide driven by a voice coil actuator and using high-resolution...

This paper presents the clinical motivation, design specifications, kinematics, statics, and actuation compensation for a newly constructed telerobotic system for Minimally Invasive Surgery (MIS) of the throat. A hybrid dual-arm telesurgical slave, with twenty joint-space Degrees of Freedom (DoF), is used in this telerobotic system to provide the necessary dexterity in deep surgical fields such...