High-Performance Motion Control With Slosh: A Constrained Sliding Mode Approach

2008 ◽  
Author(s):  
Hanz Richter ◽  
Kedar B. Karnik
Keyword(s):  
High Speed ◽  
High Performance ◽  
Design Methodology ◽  
Closed Loop ◽  
Sliding Mode ◽  
Initial Conditions ◽  
Rectilinear Motion ◽  
Industrial Setting ◽  
Open Container ◽  
Nominal Performance

The problem of controlling the rectilinear motion of an open container without exceeding a prescribed liquid level and other constraints is considered using a recently-developed constrained sliding mode control design methodology based on invariant cylinders. A conventional sliding mode regulator is designed first to address nominal performance in the sliding mode. Then an robustly-invariant cylinder is constructed and used to describe the set of safe initial conditions from which the closed-loop controller can be operated without constraint violation. Simulations of a typical transfer illustrate the usefulness of the method in an industrial setting. Experimental results corresponding to a high-speed transfer validate the theory.

Motion Control of a Container With Slosh: Constrained Sliding Mode Approach

2010 ◽  
Vol 132 (3) ◽  
Author(s):  
Hanz Richter
Keyword(s):  
Motion Control ◽  
High Speed ◽  
Sliding Mode ◽  
Initial Conditions ◽  
Cartesian Product ◽  
Linear Matrix ◽  
Open Container ◽  
Nominal Performance ◽  
Control Methodology ◽  
Safe Operating

A constrained sliding mode control methodology developed by the author is applied to the motion control of an open container filled with liquid. The objective is to control the position of the container to meet the performance and robustness requirements, and to specify a safe operating set, i.e., the set of initial conditions from which the system can be operated without exceeding a prescribed liquid level and additional constraints. A conventional sliding mode regulator is designed first to address nominal performance in the sliding mode. Then, a robustly invariant cylinder formed as the Cartesian product of an ellipsoid, and a closed interval is constructed using linear matrix inequalities. A set of constraint qualification conditions are evaluated to ensure that the intersection of the cylinder and the state constraints is robustly positively invariant, constituting the required operating set. Simulations and experimental results corresponding to a high-speed transfer validate the methodology.

scholarly journals Using Interval Analysis to Compute the Invariant Set of a Nonlinear Closed-Loop Control System

Algorithms ◽  
2019 ◽  
Vol 12 (12) ◽  
pp. 262 ◽  
Author(s):  
Swantje Romig ◽  
Luc Jaulin ◽  
Andreas Rauh
Keyword(s):  
Interval Analysis ◽  
Closed Loop ◽  
Sliding Mode ◽  
Initial Conditions ◽  
Invariant Sets ◽  
Control Synthesis ◽  
Closed Loop Control ◽  
Loop Control ◽  
Loop Control System ◽  
Bézout’S Identity

In recent years, many applications, as well as theoretical properties of interval analysis have been investigated. Without any claim for completeness, such applications and methodologies range from enclosing the effect of round-off errors in highly accurate numerical computations over simulating guaranteed enclosures of all reachable states of a dynamic system model with bounded uncertainty in parameters and initial conditions, to the solution of global optimization tasks. By exploiting the fundamental enclosure properties of interval analysis, this paper aims at computing invariant sets of nonlinear closed-loop control systems. For that purpose, Lyapunov-like functions and interval analysis are combined in a novel manner. To demonstrate the proposed techniques for enclosing invariant sets, the systems examined in this paper are controlled via sliding mode techniques with subsequently enclosing the invariant sets by an interval based set inversion technique. The applied methods for the control synthesis make use of a suitably chosen Gröbner basis, which is employed to solve Bézout’s identity. Illustrating simulation results conclude this paper to visualize the novel combination of sliding mode control with an interval based computation of invariant sets.

Robust and precision control for a directly-driven XY table

2011 ◽  
Vol 225 (5) ◽  
pp. 1107-1120 ◽  
Author(s):  
F Wang ◽  
X Zhao ◽  
D Zhang ◽  
Z Ma ◽  
X Jing
Keyword(s):  
Control System ◽  
High Speed ◽  
Design Methodology ◽  
Sliding Mode ◽  
Voice Coil Motor ◽  
Loop Model ◽  
Direct Drive ◽  
Dynamic Design ◽  
Reaching Law ◽  
Exponential Reaching Law

To provide faster, more repeatable, and stronger microelectronics bonding technology, this article presents the design and implementation of a robust and precision controller for a high-speed linear voice-coil motor, direct-drive, XY positioning table. Moreover, the dynamic design methodology of the control system for the positioning table is proposed based on electromechanical co-simulation. Using the finite-element method and dynamic analysis, the rigid–flexible coupled mechanical model of the XY table is established. With the aid of the system identification approach, the open-loop model of the control system for the X-axis table is obtained. On this basis, the proportion integration differentiation controller with incomplete derivation and the sliding mode controller (SMC) with the exponential reaching law are designed to control the X-axis table. The performances of the controllers are investigated using electromechanical co-simulations and experimental tests, and the results show that the motion overshoot and settling time are reduced using the SMC with an exponential reaching law. The SMC with the exponential reaching law also shows strong robustness against external disturbances. The experiment and co-simulation results are in good agreement, which confirms the validity and feasibility of the dynamic design methodology for a high-speed and high-accuracy positioning table based on electromechanical co-simulation.

Integrated Design and Control for a Programmable Four-Bar Linkage

1999 ◽  
Author(s):  
Q. Li ◽  
W. J. Zhang ◽  
L. S. Guo
Keyword(s):  
High Speed ◽  
Control Algorithm ◽  
Design Methodology ◽  
Motion Tracking ◽  
Closed Loop ◽  
Controller Design ◽  
Integrated Design ◽  
Dynamic Performances ◽  
And Control ◽  
Four Bar Linkage

Abstract As the demand increases for machines of high accuracy, high speed and high stiffness, programmable closed-loop linkages emerge in the development of modern machinery. A mechatronic design methodology is proposed in this paper for the integrated design of mechanical structure and control algorithm for a programmable closed-loop mechanism system. This design methodology suggests a negative mass redistribution scheme, which follows the principle of a shaking force/shaking moment balancing scheme, for the modification of an existing four-bar mechanism, with the aim to obtain a simple system dynamic model and thus to facilitate controller design. In consequence, motion tracking performance and vibration behavior of the linkage system are significantly improved by simply applying a conventional PD control algorithm. The dynamic performances are further improved by using a model-based controller. The effectiveness of the proposed methodology has been verified by simulation studies.

High-order, sliding-mode-based precise control of direct-drive systems under heavy uncertainties

2007 ◽  
Vol 221 (5) ◽  
pp. 791-805 ◽  
Author(s):  
S Bogosyan ◽  
A Arabyan
Keyword(s):  
High Speed ◽  
High Performance ◽  
Sliding Mode ◽  
High Order ◽  
The Novel ◽  
Direct Drive ◽  
Tracking Accuracy ◽  
Actuator Dynamics ◽  
Precise Position ◽  
Continuous Input

The high-performance control of direct-drive (DD) systems requires the full system dynamic effects to be taken into account owing to the eliminated gear mechanism. The actuator dynamics and structural flexibilities become of increased importance, particularly when high-speed, high-accuracy operation of lightweight structures is aimed for; however, in most related literature, these effects are neglected to avoid increased computational complexity at the expense of compromising the tracking accuracy of the system in the transient and steady state. As a solution to the problem, in this study, high-order, sliding-mode (HOSM) controllers (HOSMCs) are developed, which exploit the robustness properties of sliding-mode controllers (SMCs) while also increasing accuracy by reducing chattering effects. Different from standard HOSMCs, which are derived by artificially increasing the system order, the third-order HOSM (3-HOSM) control laws in this study are derived by including the actuator dynamics and structural flexibilities in the control design process. Two HOSMCs are developed for this purpose: one with a discontinuous input and one with a continuous input aimed at reducing chattering. The performance of the novel HOSMCs is tested by simulations for the precise position and tracking control of a one-degree-of-freedom (1DOF) DD weapon-positioning system as an example of a direct-drive system under heavy uncertainties and external disturbances. The improved accuracy obtained, particularly with the novel continuous-input 3-HOSMC, motivates the implementation of the schemes for demanding control applications under heavy uncertainties.

Closed-Loop Digital Control of an Impact Printer Hammer

1990 ◽  
Vol 112 (1) ◽  
pp. 69-75 ◽  
Author(s):  
L. E. Ryan ◽  
R. F. Stengel
Keyword(s):  
Digital Control ◽  
High Speed ◽  
Closed Loop ◽  
Initial Conditions ◽  
Proper Time ◽  
Computation Time ◽  
Magnetic Interaction ◽  
Soft Landing ◽  
High Speed Impact ◽  
Solenoid Actuator

This paper explores closed-loop digital control of a high-speed impact printer hammer in the presence of sensor measurement noise and disturbances. Conventional control of high-speed impact printers is accomplished without feedback; hence disturbances, such as mechanical and magnetic interaction between hammers and hammer settle-out period, force long delays between hammer firings to assure proper time and velocity of impact. By computer simulation, we show the feasibility of using the solenoid actuator to control both time and velocity of impact. This is accomplished by setting an initial trajectory and introducing mid-course guidance based on state estimates derived from hammer position measurements and a Kalman filter estimator. To overcome difficulties in performing necessary computations in a short time, and in synchronizing the digital system to the “real world,” the controller allows the solenoid to be commanded “on” and “off” between samples. Although the solenoid actuator produces a force in one direction only, the same control law is used to decelerate the hammer on the return trip, bringing it to a soft landing that provides satisfactory initial conditions for the next hammer command. Attention is given to computation time required, and a general scenario for real-time implementation is given.

scholarly journals The sensorless control strategy of UAV rotor motor in full speed range

2021 ◽  
Vol 261 ◽  
pp. 01010
Author(s):  
Siyuan Ma ◽  
Xiang Yu ◽  
Yunjun Guo ◽  
Rong Ran
Keyword(s):  
Control Strategy ◽  
High Speed ◽  
Closed Loop ◽  
High Efficiency ◽  
Sliding Mode ◽  
Sensorless Control ◽  
Open Loop ◽  
Speed Range ◽  
Full Speed ◽  
Position Sensorless

UAV (Unmanned Aerial Vehicle) has broad application prospects in various fields. In order to meet the needs of stability and efficiency during flight, a surface-mounted permanent magnet synchronous motor is used as its rotor motor, and a position sensorless control technology is used to control the rotor motor with high efficiency and high dynamic response. This paper proposes a position sensorless control strategy in the full speed range for the actual application requirements of UAV. In low speed ange, I/F control strategy with speed-open-loop and current-closed-loop is. In medium and high speed range, a sliding mode observer is adopted to provide estimated rotor position and speed. To achieve smooth switching from I/F control stage to speed closed-loop stage, a switching algorithm is proposed. The feasibility of the proposed hybrid control strategy is verified by simulation results.

Vacuum System to Minimize the Specimen Contamination of High-Performance EM

1977 ◽  
Vol 35 ◽  
pp. 68-69
Author(s):  
N. Yoshimura ◽  
K. Shirota ◽  
T. Etoh
Keyword(s):  
Electron Microscope ◽  
High Speed ◽  
High Performance ◽  
High Vacuum ◽  
Vacuum System ◽  
Pump System ◽  
Pumping System ◽  
Diffusion Pump ◽  
Almost All ◽  
Cascade Type

One of the most important requirements for a high-performance EM, especially an analytical EM using a fine beam probe, is to prevent specimen contamination by providing a clean high vacuum in the vicinity of the specimen. However, in almost all commercial EMs, the pressure in the vicinity of the specimen under observation is usually more than ten times higher than the pressure measured at the punping line. The EM column inevitably requires the use of greased Viton O-rings for fine movement, and specimens and films need to be exchanged frequently and several attachments may also be exchanged. For these reasons, a high speed pumping system, as well as a clean vacuum system, is now required. A newly developed electron microscope, the JEM-100CX features clean high vacuum in the vicinity of the specimen, realized by the use of a CASCADE type diffusion pump system which has been essentially improved over its predeces- sorD employed on the JEM-100C.

PHAX-SCAN: Functional integration of a Scanning Electron Microscope and an energy-dispersive x-ray analyser

1989 ◽  
Vol 47 ◽  
pp. 56-57
Author(s):  
Marc H. Peeters ◽  
Max T. Otten
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
High Speed ◽  
High Performance ◽  
Functional Integration ◽  
Energy Dispersive ◽  
X Rays ◽  
X Ray ◽  
High Speed Analysis ◽  
Scanning Electron

Over the past decades, the combination of energy-dispersive analysis of X-rays and scanning electron microscopy has proved to be a powerful tool for fast and reliable elemental characterization of a large variety of specimens. The technique has evolved rapidly from a purely qualitative characterization method to a reliable quantitative way of analysis. In the last 5 years, an increasing need for automation is observed, whereby energy-dispersive analysers control the beam and stage movement of the scanning electron microscope in order to collect digital X-ray images and perform unattended point analysis over multiple locations.The Philips High-speed Analysis of X-rays system (PHAX-Scan) makes use of the high performance dual-processor structure of the EDAX PV9900 analyser and the databus structure of the Philips series 500 scanning electron microscope to provide a highly automated, user-friendly and extremely fast microanalysis system. The software that runs on the hardware described above was specifically designed to provide the ultimate attainable speed on the system.

The bright future of digital imaging in scanning electron microscopy

1993 ◽  
Vol 51 ◽  
pp. 768-769
Author(s):  
M. T. Postek ◽  
A. E. Vladar
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Digital Imaging ◽  
High Speed ◽  
High Performance ◽  
Mass Storage ◽  
Analog To Digital ◽  
Central Processing ◽  
Digital Imaging Technology ◽  
Scanning Electron

One of the major advancements applied to scanning electron microscopy (SEM) during the past 10 years has been the development and application of digital imaging technology. Advancements in technology, notably the availability of less expensive, high-density memory chips and the development of high speed analog-to-digital converters, mass storage and high performance central processing units have fostered this revolution. Today, most modern SEM instruments have digital electronics as a standard feature. These instruments, generally have 8 bit or 256 gray levels with, at least, 512 × 512 pixel density operating at TV rate. In addition, current slow-scan commercial frame-grabber cards, directly applicable to the SEM, can have upwards of 12-14 bit lateral resolution permitting image acquisition at 4096 × 4096 resolution or greater. The two major categories of SEM systems to which digital technology have been applied are:In the analog SEM system the scan generator is normally operated in an analog manner and the image is displayed in an analog or "slow scan" mode.

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