scholarly journals Molten metal’s reaction force measurement for pressure estimation and control system construction in press casting

ACTA IMEKO ◽  
2017 ◽  
Vol 6 (2) ◽  
pp. 54
Author(s):  
Ryosuke Tasaki ◽  
Kazuhiko Terashima
Keyword(s):  
Control System ◽  
Molten Metal ◽  
Measurement System ◽  
Force Measurement ◽  
Reaction Force ◽  
Measurement Data ◽  
Estimation Method ◽  
Liquid Volume ◽  
Control Input ◽  
Pressure Estimation

<p class="Abstract"><span lang="EN-US">This paper presents a measurement system for molten metal’s reaction force and estimation of liquid pressure during pressing to control the iron product quality. We have developed a new type of casting process. In the process, molten metal is quickly filled into casting molds by high-speed pressing. Casting defects such as physical metal penetration is often caused by excess pressure. Hence, we have constructed a pressure control system using a mathematical model-based off-line simulation to derive the ideal feedforward control input of pressing. However, it is difficult to accurately control the pressure in cases of varying conditions such as liquid volume and temperature changes. Also, pressure measurements by using contact-type sensors directly is impossible for molten metal, because of the high temperature of the liquid, over 1400 °C. So, we have proposed a new pressure estimation method with force measurement data processing. Here, the exact reaction force from the molten metal must be accurately observed by a force sensor set between the upper mold and its elevating device. The viscosity coefficient can also be calculated on a real-time basis. The proposed force measurement system will realize an improved casting quality due to the effective feed-back control system.</span></p>

scholarly journals Experimental Verification of Real-Time Flow-Rate Estimations in a Tilting-Ladle-Type Automatic Pouring Machine

2021 ◽  
Vol 11 (15) ◽  
pp. 6701
Author(s):  
Yuta Sueki ◽  
Yoshiyuki Noda
Keyword(s):  
Real Time ◽  
Molten Metal ◽  
Flow Rate ◽  
Kalman Filters ◽  
Estimation Method ◽  
Estimation Methods ◽  
Liquid Volume ◽  
Model Parameters ◽  
Rate Estimation ◽  
Time Flow

This paper discusses a real-time flow-rate estimation method for a tilting-ladle-type automatic pouring machine used in the casting industry. In most pouring machines, molten metal is poured into a mold by tilting the ladle. Precise pouring is required to improve productivity and ensure a safe pouring process. To achieve precise pouring, it is important to control the flow rate of the liquid outflow from the ladle. However, due to the high temperature of molten metal, directly measuring the flow rate to devise flow-rate feedback control is difficult. To solve this problem, specific flow-rate estimation methods have been developed. In the previous study by present authors, a simplified flow-rate estimation method was proposed, in which Kalman filters were decentralized to motor systems and the pouring process for implementing into the industrial controller of an automatic pouring machine used a complicatedly shaped ladle. The effectiveness of this flow rate estimation was verified in the experiment with the ideal condition. In the present study, the appropriateness of the real-time flow-rate estimation by decentralization of Kalman filters is verified by comparing it with two other types of existing real-time flow-rate estimations, i.e., time derivatives of the weight of the outflow liquid measured by the load cell and the liquid volume in the ladle measured by a visible camera. We especially confirmed the estimation errors of the candidate real-time flow-rate estimations in the experiments with the uncertainty of the model parameters. These flow-rate estimation methods were applied to a laboratory-type automatic pouring machine to verify their performance.

scholarly journals Development of a Bendable Outsole Biaxial Ground Reaction Force Measurement System

Sensors ◽  
2019 ◽  
Vol 19 (11) ◽  
pp. 2641 ◽  
Author(s):  
Junghoon Park ◽  
Sangjoon Kim ◽  
Youngjin Na ◽  
Yeongjin Kim ◽  
Jung Kim
Keyword(s):  
Measurement System ◽  
Ground Reaction Force ◽  
Force Measurement ◽  
Reaction Force ◽  
Force Plate ◽  
Force Sensors ◽  
Measurement Systems ◽  
Cantilever Structure ◽  
Force Measurement System ◽  
Anterior Posterior

Wearable ground reaction force (GRF) measurement systems make it possible to measure the GRF in any environment, unlike a commercial force plate. When performing kinetic analysis with the GRF, measurement of multiaxial GRF is important for evaluating forward and lateral motion during natural gait. In this paper, we propose a bendable GRF measurement system that can measure biaxial (vertical and anterior-posterior) GRF without interrupting the natural gait. Eight custom small biaxial force sensors based on an optical sensing mechanism were installed in the proposed system. The interference between two axes on the custom sensor was minimized by the independent application of a cantilever structure for the two axes, and the hysteresis and repeatability of the custom sensor were investigated. After developing the system by the installation of force sensors, we found that the degree of flexibility of the developed system was comparable to that of regular shoes by investigating the forefoot bending stiffness. Finally, we compared vertical GRF (vGRF) and anterior-posterior GRF (apGRF) measured from the developed system and force plate at the same time when the six subjects walked, ran, and jumped on the force plate to evaluate the performance of the GRF measurement system.

Control of Liquid Level in Tundish of Strip Caster with Automatic Pouring System

2008 ◽  
Vol 575-578 ◽  
pp. 147-153 ◽  
Author(s):  
Yoshiyuki Noda ◽  
Hisaki Watari ◽  
Takanori Yamazaki
Keyword(s):  
Mathematical Model ◽  
Control System ◽  
Molten Metal ◽  
Liquid Level ◽  
Control Input ◽  
High Quality ◽  
Advanced Control ◽  
The Mathematical Model

This paper gives an advanced control to a strip caster with tilting-ladle-type automatic pouring system. The strip caster has been used for producing ferrous and nonferrous sheets. In the process, in order to obtain the high-quality products, it is required that the molten metal in the tundish keep the high liquid level. Therefore, the control system to liquid level in the tundish is proposed in this present paper. In this approach, the mathematical model from the control input into the motor for tilting ladle to the liquid level in the tundish is derived by using hydrodynamics. Then, for reaching quickly the molten metal to the high liquid level and keeping stably the liquid level, the control input into the motor is designed systematically by using the mathematical model. The proposed control system has advantage that it can be constructed simply. And, any sensors for measuring the liquid level are not required in the proposed system.

Controlling Propulsive Forces in Gait Initiation in Transfemoral Amputees

2008 ◽  
Vol 130 (1) ◽  
Author(s):  
Helco G. van Keeken ◽  
Aline H. Vrieling ◽  
At L. Hof ◽  
Jan P. K. Halbertsma ◽  
Tanneke Schoppen ◽  
...  
Keyword(s):  
Center Of Pressure ◽  
Force Measurement ◽  
Center Of Mass ◽  
Reaction Force ◽  
Force Plate ◽  
Measurement Data ◽  
Gait Initiation ◽  
Postural Adjustment ◽  
Applied Forces ◽  
Ankle Function

During prosthetic gait initiation, transfemoral (TF) amputees control the spatial and temporal parameters that modulate the propulsive forces, the positions of the center of pressure (CoP), and the center of mass (CoM). Whether their sound leg or the prosthetic leg is leading, the TF amputees reach the same end velocity. We wondered how the CoM velocity build up is influenced by the differences in propulsive components in the legs and how the trajectory of the CoP differs from the CoP trajectory in able bodied (AB) subjects. Seven TF subjects and eight AB subjects were tested on a force plate and on an 8m long walkway. On the force plate, they initiated gait two times with their sound leg and two times with their prosthetic leg. Force measurement data were used to calculate the CoM velocity curves in horizontal and vertical directions. Gait initiated on the walkway was used to determine the leg preference. We hypothesized that because of the differences in propulsive components, the motions of the CoP and the CoM have to be different, as ankle muscles are used to help generate horizontal ground reaction force components. Also, due to the absence of an active ankle function in the prosthetic leg, the vertical CoM velocity during gait initiation may be different when leading with the prosthetic leg compared to when leading with the sound leg. The data showed that whether the TF subjects initiated a gait with their prosthetic leg or with their sound leg, their horizontal end velocity was equal. The subjects compensated the loss of propulsive force under the prosthesis with the sound leg, both when the prosthetic leg was leading and when the sound leg was leading. In the vertical CoM velocity, a tendency for differences between the two conditions was found. When initiating gait with the sound leg, the downward vertical CoM velocity at the end of the gait initiation was higher compared to when leading with the prosthetic leg. Our subjects used a gait initiation strategy that depended mainly on the active ankle function of the sound leg; therefore, they changed the relative durations of the gait initiation anticipatory postural adjustment phase and the step execution phase. Both legs were controlled in one single system of gait propulsion. The shape of the CoP trajectories, the applied forces, and the CoM velocity curves are described in this paper.

scholarly journals An fMRI-compatible force measurement system for the evaluation of the neural correlates of step initiation

2017 ◽  
Vol 7 (1) ◽  
Author(s):  
Andrea Cristina de Lima-Pardini ◽  
Raymundo Machado de Azevedo Neto ◽  
Daniel Boari Coelho ◽  
Catarina Costa Boffino ◽  
Sukhwinder S. Shergill ◽  
...  
Keyword(s):  
Measurement System ◽  
Force Measurement ◽  
Neural Correlates ◽  
Step Initiation ◽  
Force Measurement System

scholarly journals Application of Deep Reinforcement Learning to Predict Shaft Deformation Considering Hull Deformation of Medium-Sized Oil/Chemical Tanker

2021 ◽  
Vol 9 (7) ◽  
pp. 767
Author(s):  
Shin-Pyo Choi ◽  
Jae-Ung Lee ◽  
Jun-Bum Park
Keyword(s):  
Reinforcement Learning ◽  
Reaction Force ◽  
Measurement Data ◽  
System Stability ◽  
Main Bearing ◽  
Shaft System ◽  
Novel Approach ◽  
Design Changes ◽  
Prediction Techniques ◽  
Shaft Deformation

The enlargement of ships has increased the relative hull deformation owing to draft changes. Moreover, design changes such as an increased propeller diameter and pitch changes have occurred to compensate for the reduction in the engine revolution and consequent ship speed. In terms of propulsion shaft alignment, as the load of the stern tube support bearing increases, an uneven load distribution occurs between the shaft support bearings, leading to stern accidents. To prevent such accidents and to ensure shaft system stability, a shaft system design technique is required in which the shaft deformation resulting from the hull deformation is considered. Based on the measurement data of a medium-sized oil/chemical tanker, this study presents a novel approach to predicting the shaft deformation following stern hull deformation through inverse analysis using deep reinforcement learning, as opposed to traditional prediction techniques. The main bearing reaction force, which was difficult to reflect in previous studies, was predicted with high accuracy by comparing it with the measured value, and reasonable shaft deformation could be derived according to the hull deformation. The deep reinforcement learning technique in this study is expected to be expandable for predicting the dynamic behavior of the shaft of an operating vessel.

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