Attitude Controller Design Research Articles

Flexible Controller Design of Bilateral Grasping Systems Based on a Multilateral Control Scheme

This paper describes a novel bilateral grasping control system including master-slave robots with different degree of freedom. The master and slave controllers are designed based on a multilateral control scheme. Decoupling design of force and position controllers is realized by mode transformation using the discrete Fourier transform matrices and a disturbance observer. In the proposed system, a human operator manipulates two master robots, and three slave robots grasp an object cooperatively. The proposed system makes it possible to grasp an object tightly in the slave side and to transmit feeling of grasping to a human operator vividly. The validity of the proposed method is shown by numerical and experimental results.

Constrained Control Design for Dynamic Positioning of Marine Vehicles with Control Allocation

In this paper, we address the control design problem of positioning of over-actuated marine vehicles with control allocation. The proposed design is based on a combined position and velocity loops in a multi-variable anti-windup implementation together with a control allocation mapping. The vehicle modelling is considered with appropriate simplifications related to low-speed manoeuvring hydrodynamics and vehicle symmetry. The control design is considered together with a control allocation mapping. We derive analytical tuning rules based on requirements of closed-loop stability and performance. The anti- windup implementation of the controller is obtained by mapping the actuator-force constraint set into a constraint set for the generalized forces. This approach ensures that actuation capacity is not violated by constraining the generalized control forces; thus, the control allocation is simplified since it can be formulated as an unconstrained problem. The mapping can also be modified on-line based on actuator availability to provide actuator-failure accommodation. We provide a proof of the closed-loop stability and illustrate the performance using simulation scenarios for an open-frame underwater vehicle.

Design and implementation of precise position controller of active probe of atomic force microscopy for nanomanipulation

Efficiency and accuracy of AFM-based nanomanipulation are still major problems to be solved, due to the nonlinearities and uncertainties, such as drift, creep, hysteresis, etc. The deformation of cantilevers caused by manipulation force is also one of the most major factors of nonlinearities and uncertainties. It causes difficulties in precise control of the tip position and causes the tip to miss the position of the object. In order to solve this problem, the traditional approach is to use a rigid cantilever. However, this will significantly reduce the sensitivity of force sensing during manipulation, which is essential for achieving an efficient and reliable nanomanipulation. In this paper, a kind of active AFM probe has been used to solve this problem by directly controlling the cantilever’s flexibility or rigidity during manipulation. Based on Euller-Bernoulli Model, a kind of controller of the active probe employing Periodic-Output-Feedback (POF) law is implemented. The results of simulation and experiments have demonstrated that this theoretical model and POF controller are suitable for precise position control of nanomanipulation.

Probe-based ultrahigh-density storage technology

Ultrahigh storage densities can be achieved by using a thermomechanical scanning-probe-based data-storage approach to write, read back, and erase data in very thin polymer films. High data rates are achieved by parallel operation of large two-dimensional arrays of cantilevers that can be batch fabricated by silicon-surface micromachining techniques. The very high precision required to navigate the storage medium relative to the array of probes is achieved by microelectromechanical system (MEMS)-based x and y actuators. The ultrahigh storage densities offered by probe-storage devices pose a significant challenge in terms of both control design for nanoscale positioning and read-channel design for reliable signal detection. Moreover, the high parallelism necessitates new dataflow architectures to ensure high performance and reliability of the system. In this paper, we present a small-scale prototype system of a storage device that we built based on scanning-probe technology. Experimental results of multiple sectors, recorded using multiple levers at 840 Gb/in <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> and read back without errors, demonstrate the functionality of the prototype system. This is the first time a scanning-probe recording technology has reached this level of technical maturity, demonstrating the joint operation of all building blocks of a storage device.

Nonlinear position controller design with input–output linearisation technique for an interior permanent magnet synchronous motor control system

A novel, advanced position controller design for an interior permanent magnet synchronous motor control system is proposed. The input–output linearisation technique is used to transfer the system model into a linearised system model. Then, based on the linearised system model, an H∞ controller is designed to achieve robust performance of the position control system. To improve the system performance, a load estimator is used to compensate the external load and the influence of the parameter variations as well. In addition, a maximum torque/ampere control is applied to increase the output torque of the motor. A digital signal processor, TMS 320LF2407, is used to execute the speed-loop and position-loop control algorithms. As a result, the hardware circuit is quite simple. Several experimental results show that the proposed system has fast transient responses, good load disturbance rejection responses and good tracking responses.

Design and Implementation of Robust Symmetric Attitude Controller for ETS-VIII Spacecraft

This paper studies the robust attitude control of the large flexible communication satellite ETS-VIII. As a controller candidate, we propose a two-degrees-of-freedom control based on robust direct velocity and displacement feedback, in order to develop a baseline of future controller design technology for this class of spacecraft. For this purpose, the spacecraft modeling and controller synthesis methods are discussed. Then, the controller implementation for on-orbit control experiment is shown with some simulation results.

A novel robust speed controller scheme for PMBLDC motor

The design of speed and position controllers for permanent magnet brushless DC motor (PMBLDC) drive remains as an open problem in the field of motor drives. A precise speed control of PMBLDC motor is complex due to nonlinear coupling between winding currents and rotor speed. In addition, the nonlinearity present in the developed torque due to magnetic saturation of the rotor further complicates this issue. This paper presents a novel control scheme to the conventional PMBLDC motor drive, which aims at improving the robustness by complete decoupling of the design besides minimizing the mutual influence among the speed and current control loops. The interesting feature of this robust control scheme is its suitability for both static and dynamic aspects. The effectiveness of the proposed robust speed control scheme is verified through simulations.

Finite Element Modeling of Sail Deformation Under Solar Radiation Pressure

Anumerical structural model of a thin-film sail that simulates the deformation caused by solar-radiation pressure is developed, using a geometrically nonlinear finite element method (FEM). By using the finite element presented in this study, the force and moment exerted on an arbitrarily shaped solar sail subjected to solar pressure can be calculated accurately. In addition, it is shown that the sail deformation due to a solar-pressure load can be approximated by the deformation caused by the corresponding uniform gas-pressure load. This finding will significantly simplify analyses to improve attitude controller design as well as structural design of sailcraft, because commercially available FEM software can be used for the analyses.

FLEXIBLE SPACECRAFT VIBRATION SUPPRESSION USING PWPF MODULATED INPUT COMPONENT COMMAND AND SLIDING MODE CONTROL

ABSTRACTThis paper presents a dual‐stage control system design method for the rotational maneuver and vibration stabilization of a spacecraft with flexible appendages. In this design approach, attitude control system and vibration suppression were designed separately using lower order model. The design of attitude controller was based on sliding mode control (SMC) theory leading to a discontinuous control law. This controller accomplishes asymptotic attitude maneuvering in the closed‐loop system and is insensitive to the interaction of elastic modes and uncertainty in the system. The shaped command input controller based on component synthesis vibration suppression (CSVS) method is designed for reduction of flexible mode vibration, which only requires information about natural frequency and damping of the closed system. Additionally, to extend the CSVS method to the system with on‐off actuators, pulse‐width pulse‐frequency (PWPF) modulation is employed to control the thruster firing and integrated with the CSVS method. Simulation results have been proven the potential of this technique to control flexible spacecraft.

Adaptive-backstepping-based design of a nonlinear position controller for an IPMSM servo drive

This paper presents the design of a novel nonlinear position controller for an interior permanent-magnet synchronous motor (IPMSM) servo drive. The motor model equations provide the basis for the proposed controller, which is designed with the adaptive backstepping technique. Various system uncertainties, particularly mechanical-parameter uncertainties, are incorporated in the design of the controller. Using Lyapunov's stability theory, it is verified that the control variables are asymptotically stable. The complete drive system is then simulated with MATLAB/Simulink software. Performance of the proposed adaptive-backstepping-based nonlinear position controller (ABNPC) is investigated under different dynamic operating conditions such as step changes in command positions, step changes in load, and parameter variations. The results indicate that the proposed ABNPC-based IPMSM drive could be a candidate for real-time industrial servo motor drive applications.

EXTENDING THE LINEAR QUADRATIC DESIGN OF A LAUNCH VEHICLE ATTITUDE CONTROLLER THROUGH GENETIC OPTIMIZATION

The combined LQ-genetic design of a launch vehicle attitude controller is considered, according interpolation issues. Firstly, an equivalent unstable control system - the inverted pendulum - is stated and its controllers obtained for each time instant, assuming a variant pendulum mass. Improvements are obtained when a gain smoothing factor is present in the cost function. Secondly, a launch vehicle model and its respective control system are considered. The proposed approach is applied and the results compared against the current design.

NONLINEAR ROBUST MODEL PREDICTIVE CONTROL FOR LIFTING BODY RE-ENTRY FLIGHT ATTITUDE CONTROL

The dynamics of re-entry vehicles are time varying and notoriously nonlinear due to the large flight envelope and nonlinear aerodynamic flow phenomena. Accuracy of guidance and control of the re-entry vehicle along a predefined trajectory is crucial because of operational and safety considerations. This paper presents the design of a nonlinear attitude controller based on a Robust Model Predictive Controller (RMPC) combined with Feedback Linearization of the vehicle dynamics. Since the re-entry vehicle model contains uncertainties, FBL will not fully linearize the system. This, combined with its constraint handling capabilities, is the motivation for the application of RMPC. The uncertainty is modeled as perturbations of the aerodynamic parameters within a given percentage of their nominal value. The designed controller was tested using the GESARED simulation toolbox and shows excellent performance. The state and input constraints are satisfied, and the robustness of the controller to variations in the aerodynamic parameters has increased significantly compared to a nominal, non-robust controller.

DESIGN AND CONTROL OF A FLAPPER ACTUATED BRAILLE PRINTER BASED ON PC STANDARD INTERFACES

Biomedical Engineering: Applications, Basis and CommunicationsVol. 19, No. 01, pp. 53-61 (2007) No AccessDESIGN AND CONTROL OF A FLAPPER ACTUATED BRAILLE PRINTER BASED ON PC STANDARD INTERFACESHuoy-Shyi Tsay and Fung-Huei YehHuoy-Shyi TsayDepartment of Mechanical and Electro-Mechanical Engineering, Tamkang University, 151 Ying-Chuan Road, Tamsui, Taipei Hsien, Taiwan 25137, TaiwanCorresponding author: Dr. Huoy-Shyi Tsay, Department of Mechanical and Electro-Mechanical Engineering, Tamkang University, 151 Ying-Chuan Road, Tamsui, Taipei Hsien, Taiwan 25137, Taiwan. Search for more papers by this author and Fung-Huei YehDepartment of Mechanical and Electro-Mechanical Engineering, Tamkang University, 151 Ying-Chuan Road, Tamsui, Taipei Hsien, Taiwan 25137, Taiwan Search for more papers by this author https://doi.org/10.4015/S1016237207000094Cited by:0 PreviousNext AboutSectionsPDF/EPUB ToolsAdd to favoritesDownload CitationsTrack CitationsRecommend to Library ShareShare onFacebookTwitterLinked InRedditEmail AbstractA cost-effective and portable Braille printer with low noise is designed in this study. To reach this goal, the compressive printing concept is used and the Braille typesetting, the signal transmission interface module, the signal control module, and the Braille printing cell are designed and integrated. To increase the portability, the Braille printer is designed to use A4 size paper and each page can print at most twenty-four rows and twenty-seven Braille characters in each row. The typesetting of the printing page is designed to contain twenty-seven side-by-side Braille printing cells and each printing cell contains two low cost flapper mechanisms for performing the low noise and cost-effective Braille print. The logic signal control module then controls a total of fifty-four flappers. The logic signals are transmitted through the integrated signal transmission interface module based on two common standard personal computer interfaces: Serial/RS232 and Universal Serial Bus 2.0. Subsequently, the pre-processing software is programmed based on the hardware developed. The integration of the software and hardware is successfully validated, and this newly designed Braille printer can be further used by the visually impaired for self-printing.Keywords:Braille printerFlapperRS232Universal Serial Bus References Yeh F. H., Tsay H. S., Hung H. M., Double side impact print mechanism of a Braille printer. Utility Model Patent 169846, R.O.C, 2001 . Google ScholarH. S. Tsay, F. H. Yeh and Y. C. Sung, The position control and vibration suppression design of a Braille printer, 24th National Conference on Applied and Theoretical Mechanics, ed. Chung-Li pp. J141–J148. Google Scholar Strauss C., Braille embossers. National library service for the blind and physically handicapped, Washington, DC, 2000 . Google ScholarL. Jay, J. Visual Impair. Blin. 88, 18 (1994). ISI, Google Scholar Lange M. O., Print-non-impact printer and plotter for Braille/Moon and tactile graphics. CSUN, Los Angeles, USA, 1998 . Google ScholarT. Otake, T. Saito and Y. Yonezawa, J. Microcomput. Appl. 13, 123 (1990), DOI: 10.1016/0745-7138(90)90015-Y. Crossref, Google Scholar Way T., Barner K., Towards automatic generation of tactile graphics, RESNA, Salt Lake City, USA, 1996 . Google Scholar Nippon Telesoft, Gemini User's Manual, Nippon Telesoft Co. Ltd., Tokyo, 2003 . Google ScholarF. H. Yeh, H. S. Tsay and S. H. Liang, Displays 24, 213 (2003), DOI: 10.1016/j.displa.2004.01.008. Crossref, ISI, Google ScholarF. H. Yeh, H. S. Tsay and S. H. Liang, Biomed. Eng. Appl. Basis Commun. 17, 50 (2005). Link, ISI, Google Scholar Remember to check out the Most Cited Articles! Notable Biomedical TitlesAuthors from Harvard, Rutgers University, University College London and more! FiguresReferencesRelatedDetails Recommended Vol. 19, No. 01 Metrics History Accepted 31 January 2007 KeywordsBraille printerFlapperRS232Universal Serial BusPDF download

ATTITUDE CONTROL OF SPACECRAFT WITH PARTIALLY MAGNETIC ACTUATION

In this paper the attitude control design problem for spacecraft equipped with magnetic coils and a restricted support propulsion system is analysed and two design approaches are investigated and compared: a time-invariant design coupled with a control allocation problem, and an optimal time-periodic design. A simulation case study is presented, based on the ESA Swarm mission.

Attitude Control of Quad Rotors QTW-UAV with Tilt Wing Mechanism

In this paper, we propose the autonomous attitude control of Quad Tilt Wing (QTW) -UAV. QTW-UAV can realize the vertical takeoff and landing, and hovering flight that seems to be the helicopter, and the high cruising speed that seems to be the fixed-wing aircraft by changing an angle of a rotors and wings by using tilt mechanism. Firstly, we make the attitude model of QTW-UAV by using identification method. Secondly, we designed attitude control system with kalman filter based LQI control method. And lastly, we show the experiment result. The experiment result shows model based control design are very useful for autonomous control for QTW-UAV.

Attitude stabilization with actuators subject to switching restrictions: an approach via exact relay control methods

On-off thrusters are frequently used as actuators for attitude control. Typically these thrusters are subject to switching constraints. A limit cycle is the normal steady state operation mode of such attitude control systems. This contribution deals with controller design for precision attitude stabilization using actuators whose switching restrictions are explicitly considered. An exact approach is presented using ideas from established relay control methods. The design procedure is illustrated with an attitude controller design to attain a limit cycle with prescribed characteristics

Measurements of Transient Driving Forces Generated by a Linear Motor and a Ball Screw Mechanism, and Comparisons to Those Static Characteristics

Transient driving forces generated by a linear motor and a ball screw mechanism including a rotational servomotor were measured and compared to those static characteristics. The static relationships between the motor currents and the output force (torque) were linear. In the linear motor drive system, the step response of the driving force was 1/10 slower than that of the motor current. In the rotational servomotor, the torque response was oscillatory with 800Hz frequency and 0.01 damping ratio. In the ball screw drive mechanism, the driving force response was deeply depended to the preload force and was 1/100 slower than that the motor current. It is noted that the ball screw mechanism generated the driving force after the servomotor rotated. These dynamics should be considered in a usual position control design.

Identification and Control of a Sensorized Microgripper for Micromanipulation

This paper presents the design and control of a sensorized microgripper using a voice coil motor and a flexure mechanism. To increase the gripping sensitivity, shape design and determination of sensor attachment position are performed using finite element analysis. Empirical models of the microgripper are acquired for the design of position control and gripping force control. By using the identified models, both the perfect tracking controller for position control and the adaptive zero-phase error tracking controller for force control are implemented. The effectiveness of the proposed model-based control methods is verified by experimental studies.

Neuro-fuzzy position control of demining tele-operation system based on RNN modeling

The paper considers the neuro-fuzzy position control of multi-finger robot hand in tele-operation system—an active master–slave hand system (MSHS) for demining. Recently, fuzzy control systems utilizing artificial intelligent techniques are also being actively investigated in robotic area. Neural network with their powerful learning capability are being sought as the basis for many adaptive control systems where on-line adaptation can be implemented. Fuzzy logic on the other hand has been proved to be rather popular in many control system applications providing a rule-base like structure. In this paper, the design and optimization process of fuzzy position controller is supported by learning techniques derived from neural network where a radial basis function (RBF) neural network is implemented to learn fuzzy rules and membership functions with predictor of recurrent neural network (RNN) model. The results of experiment show that based on the predictive capability of RNN model neuro-fuzzy controller with good adaptation and robustness capability can be designed.

신경회로망을 이용한 틸트로터 항공기 SCAS 설계

This paper presents the design and evaluation of a tiltrotor attitude controller. The implemented response type of the command augumentation system is Attitude Command Attitude Hold. The controller architecture can alleviate the need for extensive gain scheduling and thus has the potential to reduce development time. The control algorithm is constructed using the feedback linearization technique. And an on-line adaptive architecture that employs a neural network compensating the model inversion error caused by the deficiency of full knowledge tiltrotor aircraft dynamics is applied to augment the attitude control system. The use of Lyapunov stability analysis guarantees boundedness of the tracking error and network parameters. The performance of the controller is evaluated against ADS-33E criteria, using the nonlinear tiltrotor simulation code for Bell TR301 developed by KARI. (Korea Aerospace Research Institute)