Beyond Pull-In Stabilization of Dual Axis Micromirrors Using Fuzzy Controllers

Author(s):  
Hamid Moeenfard ◽  
Mohammad Taghi Ahmadian ◽  
Ali Soroush ◽  
Aria Alasty

Dual axis micromirrors are actuated using strongly nonlinear electrostatic actuation and their operating range suffers from the pull-in problem. So investigation of their dynamics and control issues has become a challenge for the researchers. The current paper makes use of fuzzy controllers for the purpose of stabilizing the dual axis micromirror at the desired tilt angles beyond pull-in. At first the dynamic model of the micromirror is presented. Then for the purpose of finding the linguistic laws governing the system behavior, several step voltages are introduced to the system. The proposed fuzzy controller consists of singleton fuzzifier, product inference engine and center average defuzzifier. It was observed from the simulation results that the presented controller can effectively and immediately stabilize and control the micromirror tilt angles beyond pull-in, with a short rise time and also a short overshoot.

Robotica ◽  
1988 ◽  
Vol 6 (1) ◽  
pp. 63-69 ◽  
Author(s):  
V. Potkonjak

SUMMARYThis paper discusses one problem of robot dynamics rarely mentioned in papers relevent to this field. It is the problem of torsional effects in torque transmissions (reducers, shafts, transmission chains, etc.). The problem is significant since oscillations can appear to be due to these effects. The complete dynamic model, which includes these effects, is derived and the possible simplifications considered. The position of feedback transducers is discussed since it appears as an important problem when it is intended to minimize the influence of these elastic vibrations. The discussion is based on eigenvalues and simulation results.


2015 ◽  
Vol 09 (01) ◽  
pp. 1650001 ◽  
Author(s):  
Drew Posny ◽  
Chairat Modnak ◽  
Jin Wang

We propose a general multigroup model for cholera dynamics that involves both direct and indirect transmission pathways and that incorporates spatial heterogeneity. Under biologically feasible conditions, we show that the basic reproduction number R0 remains a sharp threshold for cholera dynamics in multigroup settings. We verify the analysis by numerical simulation results. We also perform an optimal control study to explore optimal vaccination strategy for cholera outbreaks.


2011 ◽  
Vol 2-3 ◽  
pp. 302-307 ◽  
Author(s):  
Tao Yu ◽  
Qing Kai Han

In the paper, a novel new gravity-constrained (GC) three-wire-driven (TWD) parallel robot is proposed. With its mechanism model, three typical kinematics analytical models, including horizontal up-down motion, pitching motion and heeling motion and their corresponding simulations are given in detail. In static analysis, the change of tensions in the wires is calculated based on previous kinematics analysis. The simulation results show the robot has good movement stability. The paper can provide useful materials to study of dynamics and control on wire-driven robot.


Author(s):  
Yu Zhang-Wei ◽  
Liu Xiao-Feng ◽  
Li Hai-Quan ◽  
Cai Guo-Ping

With the development of space exploration, researches on space robot will cause more attentions. However, most existing researches about dynamics and control of space robot concern planar problem, and the effect of flexible panel on dynamics of the system is not considered. In this article, dynamics modeling and active control of a 6-DOF space robot with flexible panels are investigated. Dynamic model of the system is established based on the Jourdain's velocity variation principle and the single direction recursive construction method. The computed torque control method is used to design point-to-point active controller of the space robot. The validity of the dynamic model is verified through the comparison with ADAMS software; the effects of panel flexibility on the system performance and the active controller design are studied in detail. Simulation results indicate that the proposed model is effective to describe the dynamics of space robot; panel flexibility has large influence on the dynamic behavior of space robot; the designed controller can effectively make the robot reach a specified position and the elastic vibration of the panels may be suppressed simultaneously.


1997 ◽  
Vol 122 (1) ◽  
pp. 108-113 ◽  
Author(s):  
Shyh-Leh Chen ◽  
Steven W. Shaw ◽  
Hassan K. Khalil ◽  
Armin W. Troesch

The dynamics and control of a strongly nonlinear 3-DOF model for ship motion are investigated. The model describes the roll, sway, and heave motions occurring in a vertical plane when the vessel is subjected to beam seas. The ship is installed with active antiroll tanks as a means of preventing large amplitude roll motions. A robust state feedback controller for the pumps is designed that can handle model uncertainties, which arise primarily from unknown hydrodynamic loads. The approach for the controller design is a combination of sliding mode control and composite control for singularly perturbed systems, with the help of the backstepping technique. It is shown that this design can effectively control roll motions of large amplitude, including capsize prevention. Numerical simulation results for an existing fishing vessel, the twice-capsized Patti-B, are used to verify the analysis. [S0022-0434(00)02701-5]


2016 ◽  
Vol 2016 ◽  
pp. 1-17 ◽  
Author(s):  
Naif B. Almutairi ◽  
Mohamed Zribi

The control problem of gantry cranes has attracted the attention of many researchers because of the various applications of these cranes in the industry. In this paper we propose two fuzzy controllers to control the position of the cart of a gantry crane while suppressing the swing angle of the payload. Firstly, we propose a dual PD fuzzy controller where the parameters of each PD controller change as the cart moves toward its desired position, while maintaining a small swing angle of the payload. This controller uses two fuzzy subsystems. Then, we propose a fuzzy controller which is based on heuristics. The rules of this controller are obtained taking into account the knowledge of an experienced crane operator. This controller is unique in that it uses only one fuzzy system to achieve the control objective. The validity of the designed controllers is tested through extensive MATLAB simulations as well as experimental results on a laboratory gantry crane apparatus. The simulation results as well as the experimental results indicate that the proposed fuzzy controllers work well. Moreover, the simulation and the experimental results demonstrate the robustness of the proposed control schemes against output disturbances as well as against uncertainty in some of the parameters of the crane.


Author(s):  
Ji-Chul Ryu ◽  
Sunil K. Agrawal ◽  
Jaume Franch

This paper presents a methodology for trajectory planning and tracking control of a tractor with a steerable trailer based on the system’s dynamic model. The theory of differential flatness is used as the basic approach in these developments. Flat outputs are found that linearize the system’s dynamic model using dynamic feedback linearization, a subclass of differential flatness. It is demonstrated that this property considerably simplifies motion planning and the development of controller. Simulation results are presented in the paper, which show that the developed controller has the desirable performance with exponential stability.


2021 ◽  
Vol 11 (17) ◽  
pp. 7865
Author(s):  
Chokri Sendi

This paper examines the dynamics and control of a variable blade pitch wind turbine during extreme gust wind and subject to actuators saturation. The mathematical model of the wind turbine is derived using the Lagrange dynamics. The controller is formulated using the Takagi–Sugeno fuzzy model and utilizes the parallel distributor compensator to obtain the feedback control gain. The controller’s objective is to obtain the generator electromagnetic torque and the blade pitch angle to attenuate the external disturbances. The (T–S) fuzzy controller with disturbances rejection properties is developed using the linear matrix inequalities technic and solved as an optimization problem. The efficacy of the proposed (T–S) fuzzy controller is illustrated via numerical simulations.


Author(s):  
Francesco Biral ◽  
Fabrizio Zendri ◽  
Enrico Bertolazzi ◽  
Paolo Bosetti ◽  
Marco Galvani ◽  
...  

A web based VRCC (Virtual Racing Car Championship) application is here presented. The application is intended for educational purposes to teach students a variety of topics of the teaching course “Vehicle Dynamics and Control” in Mechatronics Master Degree Course; the present application forces students to understand the relevant parameters that govern the dynamic performance of racing cars. The application relies on an optimal control library, which is capable of calculating minimum lap times of a racing car on the basis of a comprehensive symbolic description of an open-wheel racing car dynamic model. Students are enrolled in a number of teams competing in a Championship to attain the minimum lap time (i.e., the pole position) on three circuits by choosing the appropriate setup of the racing car. The ranking is based on the best lap time obtained in the qualification session. The application stimulates students to adopt a multidisciplinary approach in a challenging and instructive environment, where they are in a position to apply a broad range of knowledges and abilities they have acquired during the Mechanotronics engineering course.


Author(s):  
Ji-Chul Ryu ◽  
Sunil K. Agrawal ◽  
Jaume Franch

This paper presents a methodology for trajectory planning and tracking control of a tractor with a steerable trailer based on the system’s dynamic model. The theory of differential flatness is used as the basic approach in these developments. Flat outputs are found that linearize the system’s dynamic model using dynamic feedback linearization, a subclass of differential flatness. It is demonstrated that this property considerably simplifies motion planning and the development of controller. Simulation results are presented in the paper, which show that the developed controller has the desirable performance with exponential stability.


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