Formulation and Simulations of the Conserving Algorithm for Feedback Stabilization on Rigid Body Rotations

The problem of stabilization of rigid bodies has received a great deal of attention for many years. People have developed a variety of feedback control laws to meet their design requirements and have formulated various but mostly open loop numerical algorithms for the dynamics of the corresponding closed loop systems. Since the conserved quantities such as energy, momentum, and symmetry play an important role in the dynamics, we investigate the conserved quantities for the closed loop control systems which formally or asymptotically stabilize rigid body rotation and modify the open loop numerical algorithms so that they preserve these important properties. Using several examples, the authors first use the open loop algorithm to simulate the tumbling rigid body actions and then use the resulting closed loop one to stabilize them.

Download Full-text

Interactive Modeling and Analysis of Open or Closed Loop Dynamic Systems with Redundant Actuators

Journal of Mechanical Design ◽

10.1115/1.3454073 ◽

1979 ◽

Vol 101 (3) ◽

pp. 407-416 ◽

Cited By ~ 8

Author(s):

R. J. Williams ◽

A. Seireg

Keyword(s):

Dynamic Systems ◽

Closed Loop ◽

Open Loop ◽

Rigid Bodies ◽

Dynamic Activity ◽

Modeling And Analysis ◽

Closed Loop Systems ◽

Redundant Actuators ◽

Machine Systems ◽

Input Motion

This paper deals with the development of a computer-based procedure for the modeling and analysis of large displacement dynamic systems of the open or closed loop types. The procedure facilitates the construction of the model for such systems, automatically formulates the dynamic equations and provides the solution for any given input motion. The program is capable of analyzing complex systems with redundant force actuators utilizing a linear programming optimization scheme. It incorporates an interactive graphic capability which is invaluable in the construction, modification and visual checking of a model. The modeling procedure is general in nature and is applicable to systems of many connected rigid bodies. Its capabilities are illustrated in this paper by evaluating muscle forces and joint reactions of the musculoskeletal structure during dynamic activity. The system is readily applicable to the analysis of the actuation schemes in human and animal locomotion, many classes of machine systems, as well as robots and manipulators. Although only applications to open loop mechanisms are presented in this paper, the program can be readily extended to treat closed loop systems as well.

Download Full-text

Closed-loop control of zebrafish response using a bioinspired robotic-fish in a preference test

Journal of The Royal Society Interface ◽

10.1098/rsif.2012.0540 ◽

2013 ◽

Vol 10 (78) ◽

pp. 20120540 ◽

Cited By ~ 62

Author(s):

Vladislav Kopman ◽

Jeffrey Laut ◽

Giovanni Polverino ◽

Maurizio Porfiri

Keyword(s):

Real Time ◽

Closed Loop ◽

Preference Test ◽

Open Loop ◽

Robotic Fish ◽

Colour Pattern ◽

Closed Loop Control ◽

Water Tank ◽

Loop Control ◽

Closed Loop Systems

In this paper, we study the response of zebrafish to a robotic-fish whose morphology and colour pattern are inspired by zebrafish. Experiments are conducted in a three-chambered instrumented water tank where a robotic-fish is juxtaposed with an empty compartment, and the preference of live subjects is scored as the mean time spent in the vicinity of the tank's two lateral sides. The tail-beating of the robotic-fish is controlled in real-time based on feedback from fish motion to explore a spectrum of closed-loop systems, including proportional and integral controllers. Closed-loop control systems are complemented by open-loop strategies, wherein the tail-beat of the robotic-fish is independent of the fish motion. The preference space and the locomotory patterns of fish for each experimental condition are analysed and compared to understand the influence of real-time closed-loop control on zebrafish response. The results of this study show that zebrafish respond differently to the pattern of tail-beating motion executed by the robotic-fish. Specifically, the preference and behaviour of zebrafish depend on whether the robotic-fish tail-beating frequency is controlled as a function of fish motion and how such closed-loop control is implemented.

Download Full-text

Open-loop versus closed-loop control of processor loading

Performance Evaluation ◽

10.1016/0166-5316(90)90012-8 ◽

1990 ◽

Vol 11 (3) ◽

pp. 201-208

Author(s):

Frits C. Schoute

Keyword(s):

Closed Loop ◽

Open Loop ◽

Closed Loop Control ◽

Loop Control

Download Full-text

Impedance Reduction Controller Design for Mechanical Systems

Volume 3: Nonlinear Estimation and Control; Optimization and Optimal Control; Piezoelectric Actuation and Nanoscale Control; Robotics and Manipulators; Sensing; System Identification (Estimation for Automotive Applications, Modeling, Therapeutic Control in Bio-Systems); Variable Structure/Sliding-Mode Control; Vehicles and Human Robotics; Vehicle Dynamics and Control; Vehicle Path Planning and Collision Avoidance; Vibrational and Mechanical Systems; Wind Energy Systems and Control ◽

10.1115/dscc2013-3737 ◽

2013 ◽

Cited By ~ 1

Author(s):

Hanseung Woo ◽

Kyoungchul Kong

Keyword(s):

Case Studies ◽

Closed Loop ◽

Controller Design ◽

Mechanical Impedance ◽

Open Loop ◽

Mechatronic Systems ◽

Closed Loop Systems ◽

Guaranteed Stability ◽

Reaction Forces ◽

Definition Of

Safety is one of important factors in control of mechatronic systems interacting with humans. In order to evaluate the safety of such systems, mechanical impedance is often utilized as it indicates the magnitude of reaction forces when the systems are subjected to motions. Namely, the mechatronic systems should have low mechanical impedance for improved safety. In this paper, a methodology to design controllers for reduction of mechanical impedance is proposed. For the proposed controller design, the mathematical definition of the mechanical impedance for open-loop and closed-loop systems is introduced. Then the controllers are designed for stable and unstable systems such that they effectively lower the magnitude of mechanical impedance with guaranteed stability. The proposed method is verified through case studies including simulations.

Download Full-text

Active Control of Combustion Instability Using Symmetric and Asymmetric Premix Fuel Modulation

Volume 6: Turbo Expo 2007, Parts A and B ◽

10.1115/gt2007-27342 ◽

2007 ◽

Cited By ~ 5

Author(s):

Daniel Guyot ◽

Christian Oliver Paschereit

Keyword(s):

Heat Release ◽

Closed Loop ◽

Modulation Frequency ◽

Combustion Instability ◽

Open Loop ◽

Closed Loop Control ◽

Nox Emissions ◽

Loop Control ◽

Asymmetric Modulation ◽

Control Schemes

Active instability control was applied to an atmospheric swirl-stabilized premixed combustor using open loop and closed loop control schemes. Actuation was realised by two on-off valves allowing for symmetric and asymmetric modulation of the premix fuel flow while maintaining constant time averaged overall fuel mass flow. Pressure and heat release fluctuations in the combustor as well as NOx, CO and CO2 emissions in the exhaust were recorded. In the open loop circuit the heat release response of the flame was first investigated during stable combustion. For symmetric fuel modulation the dominant frequency in the heat release response was the modulation frequency, while for asymmetric modulation it was its first harmonic. In stable open loop control a reduction of NOx emissions due to fuel modulation of up to 19% was recorded. In the closed loop mode phase-shift control was applied while triggering the valves at the dominant oscillation frequency as well as at its second subharmonic. Both, open and closed loop control schemes were able to successfully control a low-frequency combustion instability, while showing only a small increase in NOx emissions compared to, for example, secondary fuel modulation. Using premixed open loop fuel modulation, attenuation was best when modulating the fuel at frequencies different from the dominant instability frequency and its subharmonic. The performance of asymmetric fuel modulation was generally slightly better than for symmetric modulation in terms of suppression levels as well as emissions. Suppression of the instability’s pressure rms level of up to 15.7 dB was recorded.

Download Full-text

Suboptimal closed-loop control from open-loop algorithms

Proceedings of the Institution of Electrical Engineers ◽

10.1049/piee.1976.0157 ◽

1976 ◽

Vol 123 (7) ◽

pp. 713

Author(s):

F.W. Wright ◽

B. Laws

Keyword(s):

Closed Loop ◽

Open Loop ◽

Closed Loop Control ◽

Loop Control

Download Full-text

Oscillations-Induced Transitions and Their Application in Control of Dynamical Systems

Journal of Dynamic Systems Measurement and Control ◽

10.1115/1.2896147 ◽

1990 ◽

Vol 112 (3) ◽

pp. 313-319 ◽

Cited By ~ 9

Author(s):

J. Bentsman

Keyword(s):

Dynamical Systems ◽

Parabolic Equations ◽

Closed Loop ◽

Distributed Parameter ◽

Control Laws ◽

Loop Control ◽

Finite Dimensional ◽

Analytical Tools ◽

Semilinear Parabolic ◽

Qualitative Changes

Studies of the use of oscillations for control purposes continue to reveal new practically important properties unique to the oscillatory open and closed loop control laws. The goal of this paper is to enlarge the available set of analytical tools for such studies by introducing a method of analysis of the qualitative changes in the behavior of dynamical systems caused by the zero mean parametric excitations. After summarizing and slightly refining a technique developed previously for the finite dimensional nonlinear systems, we consider an extension of this technique to a class of distributed parameter systems (DPS) governed by semilinear parabolic equations. The technique presented is illustrated by several examples.

Download Full-text

Multi-Stage System Identification of a Gas Turbine

Volume 6: Ceramics; Controls, Diagnostics and Instrumentation; Education; Manufacturing Materials and Metallurgy ◽

10.1115/gt2017-64777 ◽

2017 ◽

Author(s):

Amit Pandey ◽

Maurício de Oliveira ◽

Chad M. Holcomb

Keyword(s):

Gas Turbine ◽

Closed Loop ◽

Open Loop ◽

Loop System ◽

Closed Loop Control ◽

Input Output ◽

Open Loop System ◽

Loop Control ◽

Multi Stage ◽

Identification Techniques

Several techniques have recently been proposed to identify open-loop system models from input-output data obtained while the plant is operating under closed-loop control. So called multi-stage identification techniques are particularly useful in industrial applications where obtaining input-output information in the absence of closed-loop control is often difficult. These open-loop system models can then be employed in the design of more sophisticated closed-loop controllers. This paper introduces a methodology to identify linear open-loop models of gas turbine engines using a multi-stage identification procedure. The procedure utilizes closed-loop data to identify a closed-loop sensitivity function in the first stage and extracts the open-loop plant model in the second stage. The closed-loop data can be obtained by any sufficiently informative experiment from a plant in operation or simulation. We present simulation results here. This is the logical process to follow since using experimentation is often prohibitively expensive and unpractical. Both identification stages use standard open-loop identification techniques. We then propose a series of techniques to validate the accuracy of the identified models against first principles simulations in both the time and frequency domains. Finally, the potential to use these models for control design is discussed.

Download Full-text

The Modelling, Simulation and FPGA-Based Implementation for Stepper Motor Wide Range Speed Closed-Loop Drive System Design

Machines ◽

10.3390/machines6040056 ◽

2018 ◽

Vol 6 (4) ◽

pp. 56 ◽

Cited By ~ 1

Author(s):

Chiu-Keng Lai ◽

Jhang-Shan Ciou ◽

Chia-Che Tsai

Keyword(s):

Embedded System ◽

High Speed ◽

Closed Loop ◽

Open Loop ◽

Drive System ◽

Stepper Motor ◽

Motor Drive ◽

Digital Controllers ◽

Loop Control ◽

Wide Range

Owing to the benefits of programmable and parallel processing of field programmable gate arrays (FPGAs), they have been widely used for the realization of digital controllers and motor drive systems. Furthermore, they can be used to integrate several functions as an embedded system. In this paper, based on Matrix Laboratory (Matlab)/Simulink and the FPGA chip, we design and implement a stepper motor drive. Generally, motion control systems driven by a stepper motor can be in open-loop or closed-loop form, and pulse generators are used to generate a series of pulse commands, according to the desired acceleration/run/deceleration, in order to the drive system to rotate the motor. In this paper, the speed and position are designed in closed-loop control, and a vector control strategy is applied to the obtained rotor angle to regulate the phase current of the stepper motor to achieve the performance of operating it in low, medium, and high speed situations. The results of simulations and practical experiments based on the FPGA implemented control system are given to show the performances for wide range speed control.

Download Full-text