To realize the stable tracking control of optoelectronic stabilized platform system under nonlinear friction and external disturbance, an active disturbance rejection controller (ADRC) with compensation is proposed to improve target ability anti-disturbance performance. First, a LuGre observer designed estimate behavior preliminarily suppress interference torque on system. Then, ADRC introduced...

One of the most important research field in mechatronics, and particularly in robotics, regards the estimation of the dynamic parameters of a general mechanical system. Many researchers have tried to understand how obtain a good dynamic parameters estimation and what are the best methodologies to apply in order to find them; now some already tested methods are widely available (see, for example...

This paper presents an approach for dead zone compensation in pneumatic position servo systems. The dead zone is an inherent nonlinearity in pneumatic servovalves, where for a range of input control values, the valve gives no output flow. Although pneumatic actuators are very common in industry, they have limitations in servo pneumatic applications that are caused by typical non-linearities of ...

Mechatronics is the art of directing the advances of a variety of academic and engineering areas to solve the smart machine problems. Author Supervisor Summary Title Language Keywords Document type Date www.md.kth.se This thesis treats block-oriented modelling, approximate linearization and control of a nonlinear pneumatic actuator system. The definition of the block-oriented nonlinear model is...

Nonlinear (NPID) control is implemented by varying the controller gains as a function of system state. NPID control has been previously described and implemented, and recently a constructive Lyapunov stability proof has been given. Here, NPID control analysis and design methods are extended to tracking, and to systems with state feedback and integral control. Experimental results are presented ...

This paper presents a model of a thermostatic valve based on first principles and where the hysteresis effect is modelled using an adaptive model for friction compensation. The grey box modelling approach is applied, i.e. both physical interpretation and statistical methods are used to build and validate the suggested model. The model performance is illustrated using empirical data and issues c...

This paper addresses the online grasp synthesis problem, in which statically stable grasp conngurations are to be generated given instantaneous contact information. We use the preimage of a given grasp controller to address object resolution, friction compensation , and resource allocation in a online fashion. The approach can be applied to piecewise smooth object ge-ometries, and it can be ext...

Dynamic emulation of mechanical loads presents a modern and interesting approach for testing and validating performance of electrical drives without a real mechanical load included in the test rig. The paper presents an approach to dynamic emulation of mechanical loads when the load torque and inertia mass of emulated load can be significantly greater than that of laboratory test rig. Closed-lo...

Friction appears in all mechanical systems and has a significant impact on control. Successful design of mechatronic systems requires an understanding of the effects of friction as well as techniques to compensation. Friction phenomena are complicated because they are caused by many different physical mechanisms. Friction can cause a substantial deterioration of the performance of a control sys...