scholarly journals Optimal Skyhook and Groundhook Control for Semiactive Suspension: A Comprehensive Methodology

2021 ◽  
Vol 2021 ◽  
pp. 1-21
Author(s):  
C. Steven Díaz-Choque ◽  
L. C. Félix-Herrán ◽  
Ricardo A. Ramírez-Mendoza
Keyword(s):  
Process Design ◽  
Design Parameters ◽  
Control Law ◽  
Semiactive Control ◽  
Optimal Control Strategy ◽  
Entire Vehicle ◽  
Performance Specifications ◽  
Straightforward Approach ◽  
Made In ◽  
Semiactive Suspension

This manuscript establishes a methodology that guides the designers to develop an optimal controller for a semiactive suspension system. The methodology’s processes are generally explained and straightforwardly, so a designer can extrapolate the methodology to a specific problem. Furthermore, this research presents an optimal control strategy for a semiactive control applied to a quarter vehicle model as an example of using the methodology. A particular interest is made in the advantages of such a simple synthesis and in the compromises that must be done in skyhook and groundhook control law applications. This manuscript exposes a logical and straightforward approach for choosing the controllers’ design parameters; also, efforts must be made to express precise performance specifications and constraints in the control design. The herein methodology could be relevant in the process design for intelligent suspensions, from one-quarter toward the entire vehicle.

Optimal Preview Semiactive Suspension

1996 ◽  
Vol 118 (1) ◽  
pp. 99-105 ◽  
Author(s):  
L. Jezequel ◽  
V. Roberti
Keyword(s):  
Degrees Of Freedom ◽  
Active Suspension ◽  
Control Law ◽  
Semiactive Control ◽  
Active System ◽  
Two Degrees Of Freedom ◽  
Suspension Control ◽  
Computer Controlled ◽  
Track Irregularities ◽  
Semiactive Suspension

This paper examines an optimal preview semiactive suspension of a quarter-coach model moving along randomly profiled track. This optimal computer-controlled suspension is designed only to dissipate energy, and is able to use knowledge of track irregularities over a distance L in front of the train. Thus the deformation of the track can be taken into account when calculating the semi-active suspension control law. First, the expression of the optimal preview semiactive control law is established. Then, using a two-degrees-of-freedom quarter-coach model, preview information is shown to improve the behavior of an optimal non-preview semi-active system, which can come close to the performance of an active system.

Up-flow roughing filtration: rehabilitation of a water treatment plant in Tarata, Bolivia

1998 ◽  
Vol 37 (9) ◽  
pp. 105-112 ◽  
Author(s):  
Ana María Ingallinella ◽  
Luis María Stecca ◽  
Martin Wegelin
Keyword(s):  
Water Treatment ◽  
Pilot Plant ◽  
Laboratory Tests ◽  
Treatment Plant ◽  
Water Treatment Plant ◽  
Horizontal Flow ◽  
Design Parameters ◽  
Sand Filters ◽  
Chemical Products ◽  
Made In

This paper presents the methodology used for the rehabilitation of the pretreatment stage in a water treatment plant for a village located in Bolivia which has 3500 inhabitants. The treatment plant was initially composed by horizontal-flow roughing filters and slow sand filters, but due to the high contents of colloidal turbidity of the providing source, it did not work properly. A plan of rehabilitation was made which comprised laboratory tests, pilot tests and proposal of modifications based on the results of previous stages. The laboratory tests were made in order to find the optimum conditions to coagulate the raw water. It was found that horizontal-flow roughing filters must be turned into up-flow roughing filters, so a pilot plant was built and was operated for three months in order to find suitable design parameters. The results obtained obtained during the operation of the pilot plant and the proposal of modifications are presented. The results of operation of the final plant, which are also reported, demonstrated the advantages of the up-flow roughing filtration as a pretreatment stage when it is necessary to add chemical products in small treatment plants.

scholarly journals Greedy control of cascading failures in interdependent networks

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Malgorzata Turalska ◽  
Ananthram Swami
Keyword(s):  
Optimal Control ◽  
Complex Systems ◽  
Control Strategy ◽  
Cascading Failures ◽  
Optimal Control Strategy ◽  
Supercritical Regime ◽  
Interdependent Networks ◽  
Malicious Activity ◽  
Cross System ◽  
Made In

AbstractComplex systems are challenging to control because the system responds to the controller in a nonlinear fashion, often incorporating feedback mechanisms. Interdependence of systems poses additional difficulties, as cross-system connections enable malicious activity to spread between layers, increasing systemic risk. In this paper we explore the conditions for an optimal control of cascading failures in a system of interdependent networks. Specifically, we study the Bak–Tang–Wiesenfeld sandpile model incorporating a control mechanism, which affects the frequency of cascades occurring in individual layers. This modification allows us to explore sandpile-like dynamics near the critical state, with supercritical region corresponding to infrequent large cascades and subcritical zone being characterized by frequent small avalanches. Topological coupling between networks introduces dependence of control settings adopted in respective layers, causing the control strategy of a given layer to be influenced by choices made in other connected networks. We find that the optimal control strategy for a layer operating in a supercritical regime is to be coupled to a layer operating in a subcritical zone, since such condition corresponds to reduced probability of inflicted avalanches. However this condition describes a parasitic relation, in which only one layer benefits. Second optimal configuration is a mutualistic one, where both layers adopt the same control strategy. Our results provide valuable insights into dynamics of cascading failures and and its control in interdependent complex systems.

scholarly journals Dust Explosion Prevention and Mitigation, Status and Developments in Basic Knowledge and in Practical Application

2009 ◽  
Vol 2009 ◽  
pp. 1-12 ◽  
Author(s):  
Rolf K. Eckhoff
Keyword(s):  
Process Design ◽  
Basic Knowledge ◽  
Industrial Plant ◽  
Practical Application ◽  
Process Industries ◽  
Wide Range ◽  
Firm Knowledge ◽  
Systematic Education ◽  
Training Of Personnel ◽  
Made In

Right from the early days of the process industries, continuous efforts have been made to develop and improve measures for prevention and mitigation of dust explosions in these industries. Nevertheless this hazard continues to threaten industries that manufacture, use and/or handle powders and dusts of a wide range of combustible materials. To improve methods for predicting explosion development in real industrial plant has been one major challenge. Hence, during the last years comprehensive numerical simulation codes, for addressing this problem, have been developed. Progress has also been made in other areas, for example, ignition source prevention. The importance of adopting inherently safer process design, by building on firm knowledge in powder science and technology, and of systematic education/training of personnel, is also emphasized.

Simultaneous Optimal Design of the Lyapunov-Based Semi-Active Control and the Semi-Active Vibration Control Device: Inverse Lyapunov Approach

2010 ◽  
Author(s):  
Kazuhiko Hiramoto ◽  
Taichi Matsuoka ◽  
Akira Fukukita ◽  
Katsuaki Sunakoda
Keyword(s):  
Optimal Design ◽  
Lyapunov Function ◽  
Vibration Control ◽  
Active Control ◽  
Control Device ◽  
Ball Screw ◽  
Design Parameters ◽  
Resistance Force ◽  
Control Law ◽  
Lyapunov Approach

We address a simultaneous optimal design problem of a semi-active control law and design parameters in a vibration control device for civil structures. The Vibration Control Device (VCD) that is being developed by authors is used as the semi-active control device in the present paper. The VCD is composed of a mechanism of a ball screw with a flywheel for the inertial resistance force and an electric motor with an electric circuit for the damping resistance force. A new bang-bang type semi-active control law referred to as Inverse Lyapunov Approach is proposed as the semi-active control law. In the Inverse Lyapunov Approach the Lyapunov function is searched so that performance measures in structural vibration control are optimized in the premise of the bang-bang type semi-active control based on the Lyapunov function. The design parameters to determine the Lyapunov function and the design parameters of the VCD are optimized for the good performance of the semi-active control system. The Genetic Algorithm is employed for the optimal design.

scholarly journals Polyadic Cantor Fractal Ultrasonic Lenses: Design and Characterization

2018 ◽  
Vol 8 (8) ◽  
pp. 1389 ◽  
Author(s):  
Sergio Castiñeira-Ibáñez ◽  
Daniel Tarrazó-Serrano ◽  
Jose Fuster ◽  
Pilar Candelas ◽  
Constanza Rubio
Keyword(s):  
Thermal Ablation ◽  
Dynamic Control ◽  
Design Parameters ◽  
Medical Applications ◽  
Curved Surfaces ◽  
Ultrasonic Beam ◽  
Acoustic Lens ◽  
Acoustic Profile ◽  
Made In

Traditional acoustic lenses modulate the ultrasonic beam due to their curved surfaces and the refractive material of which they are made. In this work, a different type of acoustic lens, based on Polyadic Cantor Fractals (PCF), is presented and thoroughly analyzed. These new Polyadic Cantor Fractal Lenses (PCFLs) are completely flat and easy to build, and they present interesting modulation capabilities over the acoustic profile. The dependence of the focusing profile on the PCFL design parameters is fully characterized, and it is shown that certain design parameters provide a dynamic control, which is critical in many medical applications such as thermal ablation of tumors.

Scheduling Strategy of Multiple Semi-Active Controllers With Information on the Disturbance and the Structural Response

2016 ◽  
Author(s):  
Kazuhiko Hiramoto ◽  
Taichi Matsuoka ◽  
Katsuaki Sunakoda
Keyword(s):  
Optimal Control ◽  
Control System ◽  
Active Control ◽  
Structural Response ◽  
Design Parameters ◽  
Control Law ◽  
Control Performance ◽  
Multiple Control ◽  
Control Laws ◽  
Scheduling Strategy

A scheduling strategy of multiple semi-active control laws for various earthquake disturbances is proposed to maximize the control performance. Generally, the semi-active controller for a given structural system is designed as a single control law and the single control law is used for all the forthcoming earthquake disturbances. It means that the general semi-active control should be designed to achieve a certain degree of the control performance for all the assumed disturbances with various time and/or frequency characteristics. Such requirement on the performance robustness becomes a constraint to obtain the optimal control performance. We propose a scheduling strategy of multiple semi-active control laws. Each semi-active control law is designed to achieve the optimal performance for a single earthquake disturbance. Such optimal control laws are scheduled with the available data in the control system. As the scheduling mechanism of the multiple control laws, a command signal generator (CSG) is defined in the control system. An artificial neural network (ANN) is adopted as the CSG. The ANN-based CSG works as an interpolator of the multiple control laws. Design parameters in the CSG are optimized with the genetic algorithm (GA). Simulation study shows the effectiveness of the approach.

A study on a new criterion for minimum-energy perfect control in the state-space framework

2019 ◽  
Vol 233 (7) ◽  
pp. 779-787 ◽  
Author(s):  
Wojciech P Hunek ◽  
Marek Krok
Keyword(s):  
Energy Cost ◽  
Control Algorithm ◽  
Minimum Energy ◽  
Energy Performance ◽  
Control Law ◽  
Performance Simulation ◽  
New Approach ◽  
Energy Behavior ◽  
New Criterion ◽  
Made In

In this article, an advanced study concerning the energy cost of the perfect control algorithm is provided. An application of different nonunique matrix inverses into perfect control law has resulted in remarkable influence on both control and state signals. Following the newly obtained issues, covering the minimum-energy behavior, a new related criterion is proposed here. Based on deterministic norm we can, in a simple way, estimate the crucial energy performance. Simulation examples made in MATLAB/Simulink environment show the high potential of a new approach considered in the article.

Compression Molding Cure Cycle Modelling and Optimization for Large Polymeric Composite Parts Processing

2015 ◽  
Vol 772 ◽  
pp. 257-262 ◽  
Author(s):  
I.V. Tarasov ◽  
S.N. Shevtsov ◽  
I.V. Zhilyaev ◽  
E.E. Orozaliev
Keyword(s):  
Process Design ◽  
Three Dimensional ◽  
Polymeric Composite ◽  
Thermal Control ◽  
Element Model ◽  
Compression Molding ◽  
Structural Features ◽  
Control Law ◽  
Suggested Approach ◽  
Simulation And Optimization

In order to improve quality and productivity of polymeric composites production we suggest the technique of process simulation and optimization for large parts manufactured by compression molding. Optimal process design includes coupled heat transfer / thermo kinetic cure process formulation, its three-dimensional finite element model (FEM) implementation, its transient analysis at the parameterized thermal control law, and Pareto-based optimization, at which we determine control law parameters ensuring minimum standard deviations of the degree of cure within the cured body. We illustrate this approach via examples of two distinct cases of closed mould design concepts: one for moulds heated in autoclaves by the pressurized heated gas, which acts on the mould surface almost uniformly, and another for moulds with independently controlled built-in electrical heaters such as strip heaters or heated platens that are positioned along the length of the die at locations determined by structural features of the cured part. The suggested approach makes the process design more predictable, easier, faster, and more reliable. It can be adapted to specific manufacturing conditions and allows optimizing tools design and processing conditions before the mould and process control are made.

Passive bipedal running

1990 ◽  
Vol 240 (1297) ◽  
pp. 107-134 ◽  
Keyword(s):  
Mechanical Design ◽  
Human Locomotion ◽  
Design Parameters ◽  
Dynamic Mode ◽  
Control Law ◽  
Wide Range ◽  
Approach Zero ◽  
Insight Into ◽  
Natural Dynamic ◽  
Careful Design

Human-like running is a natural dynamic mode of a simple mechanical biped. Such a machine consists of two telescoping legs with linear springs, connected by a hip joint with a torsional spring. It will run passively; no pattern of forcing is required to generate the gait. With careful design its energy consumption can approach zero, but in any case the passive cycle can be ‘pumped' by various means to sustain running over a range of speeds and slopes. Passive running can also be realized over a wide range of mechanical design parameters. Some parameter sets produce cycles that are inherently stable; otherwise the mode can be actively stabilized by a simple control law. Thus the passive running model offers an effective foundation for design of practical running machines, and also provides an insight into the physics of human locomotion.

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