Optimum Pressure Control of Molten Metals for Casting Production Using a Novel Greensand Mold Press Casting Method

This paper presents a novel method of sand mold press casting. In this process, molten metal is poured into a drag mold, and then the cope mold is placed on top of the drag mold, and the two molds are matched. The mold design for casting, the pouring control and the velocity control of the press have been previously clarified as key factors in the manufacture of sound products. This paper presents methods for modeling and control of the molten metal’s pressure for novel sand press casting technique. Substituting detailed information for the complex mold shape, the poured volume and initial temperature into a developed control input generator, an optimum pressing velocity design and a robust design for defect-free production are proposed by the sequential control algorithm based on the construction of an inverse system comprised of a sequential switching from higher to lower speed. The effectiveness of adaptive press casting is demonstrated by using CFD model simulations.

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Dynamic Modeling and Control of Packing Pressure in Injection Molding

Journal of Engineering Materials and Technology ◽

10.1115/1.2904280 ◽

1994 ◽

Vol 116 (2) ◽

pp. 244-249 ◽

Cited By ~ 8

Author(s):

J. Hu ◽

J. H. Vogel

Keyword(s):

Injection Molding ◽

Closed Loop ◽

Good Control ◽

Pressure Control ◽

Physical Parameters ◽

Closed Loop System ◽

Modeling And Control ◽

Packing Pressure ◽

And Control ◽

Plastic Injection

A dynamic model of injection molding developed from physical considerations is used to select PID gains for pressure control during the packing phase of thermo-plastic injection molding. The relative importance of various aspects of the model and values for particular physical parameters were identified experimentally. The controller gains were chosen by pole-zero cancellation and root-locus methods, resulting in good control performance. Both open and closed-loop system responses were predicted and verified, with good overall agreement.

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Modeling and Control of a Rotary Crane

Journal of Dynamic Systems Measurement and Control ◽

10.1115/1.3140721 ◽

1985 ◽

Vol 107 (3) ◽

pp. 200-206 ◽

Cited By ~ 61

Author(s):

Y. Sakawa ◽

A. Nakazumi

Keyword(s):

Feedback Control ◽

Equilibrium State ◽

Open Loop ◽

The State ◽

Control Input ◽

Loop Control ◽

Modeling And Control ◽

Control Scheme ◽

Rotary Crane ◽

And Control

In this paper we first derive a dynamical model for the control of a rotary crane, which makes three kinds of motion (rotation, load hoisting, and boom hoisting) simultaneously. The goal is to transfer a load to a desired place in such a way that at the end of transfer the swing of the load decays as quickly as possible. We first apply an open-loop control input to the system such that the state of the system can be transferred to a neighborhood of the equilibrium state. Then we apply a feedback control signal so that the state of the system approaches the equilibrium state as quickly as possible. The results of computer simulation prove that the open-loop plus feedback control scheme works well.

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Modeling and Control of Crane Overload Protection During Marine Lifting Operation Based on Model Predictive Control

Volume 9: Offshore Geotechnics; Torgeir Moan Honoring Symposium ◽

10.1115/omae2017-62003 ◽

2017 ◽

Cited By ~ 1

Author(s):

Zhengru Ren ◽

Roger Skjetne ◽

Zhen Gao

Keyword(s):

Model Predictive Control ◽

Predictive Control ◽

Pid Controller ◽

Degrees Of Freedom ◽

Multiple Shooting ◽

Control Input ◽

Lumped Mass ◽

Modeling And Control ◽

Overload Protection ◽

And Control

This paper deals with a nonlinear model predictive control (NMPC) scheme for a winch servo motor to overcome the sudden peak tension in the lifting wire caused by a lumped-mass payload at the beginning of a lifting off or a lowering operation. The crane-wire-payload system is modeled in 3 degrees of freedom with the Newton-Euler approach. Direct multiple shooting and real-time iteration (RTI) scheme are employed to provide feedback control input to the winch servo. Simulations are implemented with MATLAB and CaSADi toolkit. By well tuning the weighting matrices, the NMPC controller can reduce the snatch loads in the lifting wire and the winch loads simultaneously. A comparative study with a PID controller is conducted to verify its performance.

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Incorporating Practical Laboratory Experiments to Reinforce Dynamic Systems and Control Concepts

Volume 7: Engineering Education and Professional Development ◽

10.1115/imece2009-10135 ◽

2009 ◽

Cited By ~ 2

Author(s):

Melody L. Baglione

Keyword(s):

Dynamic Systems ◽

Laboratory Experiments ◽

Pressure Control ◽

Lessons Learned ◽

Student Groups ◽

Modeling And Control ◽

Faculty Interaction ◽

Hands On ◽

Systems And Control ◽

And Control

The Cooper Union is developing a new simultaneous lecture and laboratory approach to address the pedagogical challenge of finding the appropriate balance between theory and hands-on experimentation in teaching dynamic systems and control concepts. The new approach dedicates one hour each week to laboratory experiments with the class subdivided into small student groups having greater faculty interaction. Bench top experiments from National Instruments and Quanser include DC motor and inverted pendulum modeling and control workstations. Process control test rigs from Feedback Inc. include level, flow, temperature, and pressure control trainers. Devoting significant time to laboratory experiments gives students the opportunities to fully appreciate feedback control concepts and to acquire valuable practical skills. This paper discusses the new instructional approach, preliminary results, lessons learned, and future plans for improving the systems and control curriculum.

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Novel Method for the Modeling and Control Investigation of Efficient Swimming for Robotic Fish

IEEE Transactions on Industrial Electronics ◽

10.1109/tie.2011.2151812 ◽

2012 ◽

Vol 59 (8) ◽

pp. 3176-3188 ◽

Cited By ~ 49

Author(s):

Li Wen ◽

Tianmiao Wang ◽

Guanhao Wu ◽

Jianhong Liang ◽

Chaolei Wang

Keyword(s):

Robotic Fish ◽

Modeling And Control ◽

Novel Method ◽

And Control

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Sydney Metro and Melbourne Metro Rail Stochastic Comparison and Review

International Journal of Strategic Engineering ◽

10.4018/ijose.2021070103 ◽

2021 ◽

Vol 4 (2) ◽

pp. 28-38

Author(s):

Koorosh Gharehbaghi ◽

Kathryn M. Robson ◽

Neville Hurst ◽

Matt Myers

Keyword(s):

Performance Enhancement ◽

Stochastic Comparison ◽

Rail Transportation ◽

The Novel ◽

Key Factors ◽

Smart System ◽

Modeling And Control ◽

Transportation Sector ◽

And Control ◽

Control Apparatus

This paper aims to review an innovative artificial intelligence (AI) apparatus to enhance the rail transportation performance. In this light, the Sydney Metro and Melbourne Metro rail will be compared, since both of these Australian rail networks employ complex AI as part of their overall performance enhancement schemes. These two case studies further highlight the novel critical aspects of AI in rail transportation sector such as recalibration through smart system design and automation, nonlinear controls and precise design, modeling and control apparatus, and so on. As a part of such a view, different aspects of AI systems such as increased reliability and safety were also investigated. This research found that with such enhancements of system performance, the overall transportation functioning would ultimately be significantly improved. Subsequently, AI in the Australian context can be further refined based on comprehensive integration of the key factors.

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Dynamic Modeling and Control of a Ball-Joint-Like Variable-Reluctance Spherical Motor

Journal of Dynamic Systems Measurement and Control ◽

10.1115/1.2801148 ◽

1996 ◽

Vol 118 (1) ◽

pp. 29-40 ◽

Cited By ~ 64

Author(s):

Kok-Meng Lee ◽

Ronald B. Roth ◽

Zhi Zhou

Keyword(s):

Dynamic Modeling ◽

Rotor Dynamics ◽

Inverse Model ◽

Control Input ◽

Forward Dynamics ◽

Modeling And Control ◽

Spherical Motor ◽

Variable Reluctance ◽

Robot Wrist ◽

And Control

Examination of existing joint designs for robot wrist applications has indicated that a spherical wrist motor offers a major performance advantage in trajectory planning and control as compared to the popular three-consecutive-rotational joint wrist. The tradeoff, however, is the complexity of the dynamic modeling and control. This paper presents the dynamic modeling and the control strategy of a three degree-of-freedom (DOF) variable-reluctance (VR) spherical motor which presents some attractive possibilities by combining pitch, roll, and yaw motion in a single joint. The spherical motor dynamics consist of the rotor dynamics and a torque model. The torque model is described as a function of coil excitations and a permeance model in terms of the relative position between the rotor and the stator. Both the forward dynamics which determine the rotor motion as a result of activating the electromagnetic coils and the inverse model which determines the coil excitations required to generate the desired torque are derived in this paper. The solution to the forward dynamics of the spherical motor is unique, but the inverse model has many solutions and therefore an optimization is desired. Experimental results verifying the dynamic model are presented. The control of a VR spherical motor consists of two parts; namely, the control of the rotor dynamics with the actuating torque as system input, and the determination of the optimal electrical inputs for a specified actuating torque. The simulation results and implementation issues in determining the optimal control input vectors are addressed. It is expected that the resulting analysis will serve as a basis for dynamic modeling, motion control development, and design optimization of the VR spherical motor.

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Modeling and Control of a Hybrid Opposed Piston Engine

10.1115/icef2021-67541 ◽

2021 ◽

Author(s):

Joseph Drallmeier ◽

Jason B. Siegel ◽

Robert Middleton ◽

Anna G. Stefanopoulou ◽

Ashwin Salvi ◽

...

Keyword(s):

Exchange Process ◽

Tracking Error ◽

Control Input ◽

Hybrid Architecture ◽

Electric Motors ◽

Linear Quadratic ◽

Modeling And Control ◽

1D Model ◽

Gas Exchange Process ◽

And Control

Abstract This paper presents the modeling and control of an opposed piston (OP) engine in a novel hybrid architecture. The OP engine was selected for this work due to the inherent thermody-namic benefits and the balanced nature of the engine. The typical geartrain required on an OP engine was exchanged for two electric motors, significantly reducing friction and decoupling the crankshafts. By using the motors to control the crankshaft motion profiles, this configuration introduces capabilities to dynamically vary compression ratio, combustion volume, and scavenging dynamics. To realize these opportunities, a model of the system capturing the instantaneous engine dynamics is essential along with methodology to regulate the crankshaft’s rotational dynamics utilizing the electric motors. The modeling presented here couples a 1D model capturing the gas exchange process during scavenging and a 0D model of the crankshaft dynamics and the heat release profile due to combustion. With the use of this model, a linear quadratic controller with reference feedforward was designed to track the crankshaft motion trajectory. Experimental results are used to validate the model and controller performance. These results highlight the sensitivity to model uncertainty at points with high cylinder pressure, leading to large differences in control input near minimum volume. The proposed controller is, however, still able to maintain tracking error for crankshaft position below ± 1 degree.

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Passive Pneumatic Teleoperation System

ASME/BATH 2013 Symposium on Fluid Power and Motion Control ◽

10.1115/fpmc2013-4464 ◽

2013 ◽

Cited By ~ 3

Author(s):

Aly Elmasry ◽

Matthias Liermann

Keyword(s):

Transmission Lines ◽

Force Feedback ◽

Pressure Control ◽

Modeling And Control ◽

Extra Effort ◽

Physical Connection ◽

Control Scheme ◽

Set Up ◽

And Control ◽

The Mathematical Model

This paper describes the modeling and control of a pneumatic tele-operation scheme, where the connection of master and slave cylinder is realized signal based but also physically via long transmission lines. The system is called passive because of the passive physical connection, which can also serve as a safety fallback solution. The advantage of this scheme is that a limited force feedback is realized with a minimum of extra effort in comparison to a teleportation system without force feedback. The stiffness of the physical connection is enhanced through a cascaded position and pressure control scheme with two proportional valves as actuators for each pneumatic line. The paper presents the mathematical model of the setup, which is used to determine the relative stability of the dynamic system as a function of control parameters. An experimental setup is presented which was set up to validate the system model. For a distance of 5 m between master and slave cylinder a stiffness of 2.4 N/mm could be established.

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