Contribution to Computer Control and Optimization of Hydro-Abrasive Jet Machining Process

ASME 1991 Computers in Engineering Conference: Volume 2 — Finite Elements/Computational Geometry; Computers in Education; Robotics and Controls ◽

10.1115/cie1991-0175 ◽

1991 ◽

Author(s):

Roberto Groppetti ◽

Giuseppe Comi

Keyword(s):

Real Time ◽

Process Model ◽

Wide Spectrum ◽

Computer Control ◽

Process Condition ◽

Machining Process ◽

Process Variables ◽

Real Time Control ◽

Machining Conditions ◽

Abrasive Jet Machining

Abstract Hydro-Abrasive Jet Machining (HAJM) has demonstrated its suitability for several applications in the machining of a wide spectrum of materials (metals, polymers, ceramics, fibre reinforced composites, etc.). The paper is a contribution to the computer control, integration and optimization of HAJM process in order to establish a hierarchical control architecture and a platform for the implementation of a real-time Adaptive Control Optimization (ACO) module. The paper presents the approach followed and the main results obtained during the development and implementation of a HAJM cell and its computerized controller. A critical analysis of the process variables available in the literature is presented, in order to identify the process variables and to define a process model suitable for HAJM real-time control and optimization. Besides for HAJM computer control, in order to correlate process variables and parameters with machining results, a process model and an optimization procedure are necessary in order to avoid expensive and time-consuming experiments for the determination of optimal machining conditions. The paper presents the configuration of the cell and the specific components adopted in order to make possible a fully computerized control of the process, and the architecture of the controller, capable to manage the several logical and analogical signals from the different modules of the cell, for multiprogramming, process monitoring, controlling, process parameters predetermination, process condition multiobjective optimization. A prediction and an optimization model is presented allowing the identification of optimal machining conditions using multiobjective programming. This model is based on the definition of an economy function and a productivity function, with suitable constraints relevant to the required machining quality, the required kerfing depth and the available resources. A test case based on experimental results is discussed in order to validate the model.

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SPC-Based Real-Time Control Method for CNC Machining Quality

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.42.263 ◽

2010 ◽

Vol 42 ◽

pp. 263-267

Author(s):

Xin Long Kang ◽

Dong Man Yu ◽

Xue Ling Yang ◽

Di Wang

Keyword(s):

Real Time ◽

High Precision ◽

Control Method ◽

Cnc Machining ◽

Machining Process ◽

Real Time Control ◽

The Real ◽

Machining Quality ◽

Time Control ◽

Process System

This paper presents the methods and applications for the real-time control of CNC machining process quality in detail and clarifies the objectives of SPC for CNC machining, in order to enhance the understanding of the factors that cause instability to process system. Also, this paper adopts the methods and procedures for SPC to effectively serve the production of high-precision products for enterprises, in order to meet customers’ requirements and expectations.

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An integrated software architecture for the pollution-based real-time control of urban drainage systems

Journal of Hydroinformatics ◽

10.2166/hydro.2021.149 ◽

2021 ◽

Author(s):

Luis Romero ◽

Bernat Joseph-Duran ◽

Congcong Sun ◽

Jordi Meseguer ◽

Gabriela Cembrano ◽

...

Keyword(s):

Software Architecture ◽

Real Time ◽

Process Model ◽

Drainage System ◽

Urban Drainage ◽

Real Time Control ◽

Simulation And Optimization ◽

Management Scenario ◽

Time Control ◽

Integrated Software

Abstract This paper presents a complete methodology for the development of an integrated software architecture, which can achieve a closed-loop application between the integrated real-time control (RTC) and a virtual reality simulation for the urban drainage system (UDS). Quality measurements are considered during the simulation and optimization process. Model predictive control (MPC) and rule-based control (RBC) are the two main RTC methods embedded in this architecture. The proposed integration environment allows the different software components to efficiently and effectively communicate and work in a system-wide way, as well as to execute all the necessary steps regarding input parameters management, scenario configuration and results extraction. The proposed approaches are implemented into a pilot based on the Badalona UDS (Spain). Results from different scenarios with individual control approaches and rain episodes are evaluated and discussed.

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Ultrafast Laser-Induced Breakdown Spectroscopy and Application to Real-Time Control of Ultrafast Laser Micromachining Process

Heat Transfer: Volume 3 ◽

10.1115/ht2003-47068 ◽

2003 ◽

Cited By ~ 2

Author(s):

Tao Tong ◽

Jinggao Li ◽

Jon P. Longtin

Keyword(s):

Real Time ◽

Laser Micromachining ◽

Ultrafast Laser ◽

Machining Process ◽

Laser Induced Breakdown Spectroscopy ◽

Real Time Control ◽

Breakdown Spectroscopy ◽

Time Control ◽

Laser Induced Breakdown ◽

Micro Structures

A significant obstacle in ultrafast laser micromachining of multi-layer or heterogeneous micro-structures is the lack of an online diagnostic method to determine which material is being ablated during the material removal process. This problem arises because ultrafast lasers are generally insensitive to the material being processed. One promising technique to address this problem is the use of laser-induced breakdown spectroscopy (LIBS) by which the plasma generated during the laser-material interaction can be collected and analyzed to provide information regarding the elemental composition of the mate-rial being ablated. In this work, a real-time feedback control system for the ultrafast laser micromachining process based on the LIBS technique is built. The ultrafast LIBS signal is first characterized to prove the feasibility. Characteristics of spectral emission, temporal evolution, spatial heterogeneity of the ultrafast LIBS signal, effects from laser machining factors, etc., are discussed. Comparison methods for identifying the material emission patterns are then studied. Effective algorithms from the study are implemented into the control system software, SPECOMP, developed in the laboratory. Issues on the real-time control process are discussed. The real-time controlled machining process has then been applied to the machining of micro-structures on thermal sprayed material. Compared to the passive machining process without any such feedback control, SPECOMP system provides several important advantages including less damage to the substrate layer, shortened machining time, and more uniform feature sizes.

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A Real Time Control Architecture for Continuously Managing Patients in a Care Unit

Methods of Information in Medicine ◽

10.1055/s-0038-1634619 ◽

1995 ◽

Vol 34 (05) ◽

pp. 475-488

Author(s):

B. Seroussi ◽

J. F. Boisvieux ◽

V. Morice

Keyword(s):

Real Time ◽

Linear Time ◽

Treatment Plan ◽

Control Architecture ◽

Real Time Control ◽

Time Representation ◽

Time Control ◽

Continuous Support ◽

Definition Of ◽

Computerized System

Abstract:The monitoring and treatment of patients in a care unit is a complex task in which even the most experienced clinicians can make errors. A hemato-oncology department in which patients undergo chemotherapy asked for a computerized system able to provide intelligent and continuous support in this task. One issue in building such a system is the definition of a control architecture able to manage, in real time, a treatment plan containing prescriptions and protocols in which temporal constraints are expressed in various ways, that is, which supervises the treatment, including controlling the timely execution of prescriptions and suggesting modifications to the plan according to the patient’s evolving condition. The system to solve these issues, called SEPIA, has to manage the dynamic, processes involved in patient care. Its role is to generate, in real time, commands for the patient’s care (execution of tests, administration of drugs) from a plan, and to monitor the patient’s state so that it may propose actions updating the plan. The necessity of an explicit time representation is shown. We propose using a linear time structure towards the past, with precise and absolute dates, open towards the future, and with imprecise and relative dates. Temporal relative scales are introduced to facilitate knowledge representation and access.

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