Communication and control in small batch part manufacturing

This paper reports on the development of a real-time control network as an integrated part of a shop floor control system for small batch part manufacturing. The shop floor control system is called the production control system (PCS). The PCS aims at an improved control of small batch part manufacturing systems, enabling both a more flexible use of resources and a decrease in the economical batch size. For this, the PCS integrates various control functions such as scheduling, dispatching, workstation control and monitoring, whilst being connected on-line to the production equipment on the shop floor. The PCS can be applied irrespective of the level of automation on the shop floor. The control network is an essential part of the PCS, as it provides a real-time connection between the different modules (computers) of the PCS, which are geographically distributed over the shop floor. An overview of the requirements of such a control network is given. The description of the design includes the services developed, the protocols used and the physical layout of the network. A prototype of the PCS, including the control network, has been installed and tested in a pilot plant. The control network has proven that it can supply a manufacturing environment, consisting of equipment from different vendors with different levels of automation, with a reliable, low cost, real-time communication facility

The Factory of the Future

A brief history of aircraft production techniques is given. A flexible machining cell is then described. It is a computer controlled system capable of performing 4-axis machining part cleaning, dimensional inspection and materials handling functions in an unmanned environment. The cell was designed to: allow processing of similar and dissimilar parts in random order without disrupting production; allow serial (one-shipset-at-a-time) manufacturing; reduce work-in-process inventory; maximize machine utilization through remote set-up; maximize throughput and minimize labor

Implementation of automated assembly

Research has shown that about 60 - 80% wealth producing activities is related to manufacturing in major industrial countries. Increased competition in industry has resulted in a greater emphasis on using automation to improve productivity and quality and also to reduce cost. Most of the manufacturing works such as machining, painting, storage, retrieval, inspection and transportation have changed to automation successfully, except assembly. Manual assembly is predominant over automatic assembly techniques due to inherent assembly problem and the fact that the assembly machines lack the innate intelligence of human operator and lack sufficient flexibility to changeover when product designs and market demands change. With the advent of flexible manufacturing systems, which involve very large capital costs and complex interactions. For the reduction the risk of the investment and analyze the system, simulation is a valuable tool in planning the systems and in analyzing their behavior, and get the best use of them. This thesis applies animation techniques to simulate an automatic assembly system. In chapter 1 to 9, we cover some of the fundamental concepts and principles of automatic assembly and simulation. Some manufacturers put the subject of part orientation first on their list of priorities; but design for assembly (DFA) techniques have proven extremely valuable in developing better assembly techniques and ultimately, better products. We discuss DFA in chapter 1, part feeding and orientation in chapter 2. Chapter 3, 4 and 5 are concerned with assembly process, machines and control system, respectively. Annual sales for industrial robots have been growing at the rate of about 25 percent per year in major industrial countries, we review the robot application in chapter 6. The cost of material handling is a significant portion of the total cost of production, material storage uses valuable space and consumes investment, we cover these two topics in chapter 7 and 8. Chapter 9 is concerned with simulation. In chapter 10, 11,12 and 13, we implement a software package IGRIP to build a model of an automatic assembly system and analyze the result

The integration of process planning and machine loading in small batch part manufacturing

PART is a highly automated planning system in which both process and production planning functions are integrated. This paper discusses a method to improve machine tool selection in process planning by integration with loading. A method is presented to select the best process plan from a number of possible alternatives taking into account the limited availability of resources. Various aspects of the quality of a process plan are evaluated and expressed in the so-called evaluation time. To prevent redundant work, partly worked out process plans are considered as alternatives. The consequences of the different alternatives have to be estimated which includes the estimation of machining times. The loading problem is modelled as the minimization of the total evaluation time for a given order set, subjected to capacity constraints

A strategy for achieving manufacturing statistical process control within a highly complex aerospace environment

This paper presents a strategy to achieve process control and overcome the previously mentioned industry constraints by changing the company focus to the process as opposed to the product. The strategy strives to achieve process control by identifying and controlling the process parameters that influence process capability followed by the implementation of a process control framework that marries statistical methods with lean business process and change management principles. The reliability of the proposed strategy is appraised using case study methodology in a state of the art manufacturing facility on Multi-axis CNC machine tools

Intelligent systems in manufacturing: current developments and future prospects

Global competition and rapidly changing customer requirements are demanding increasing changes in manufacturing environments. Enterprises are required to constantly redesign their products and continuously reconfigure their manufacturing systems. Traditional approaches to manufacturing systems do not fully satisfy this new situation. Many authors have proposed that artificial intelligence will bring the flexibility and efficiency needed by manufacturing systems. This paper is a review of artificial intelligence techniques used in manufacturing systems. The paper first defines the components of a simplified intelligent manufacturing systems (IMS), the different Artificial Intelligence (AI) techniques to be considered and then shows how these AI techniques are used for the components of IMS

A framework of justification criteria for advanced manufacturing technology implementation in small and medium enterprises

Today in order to stay in businesses and prosper, Small and Medium Enterprises (SMEs) are seeking higher electiveness and competitiveness across the entire cycle of marketing, product design, manufacture, test and sales. SMEs play an increasingly important role in all aspects of competitiveness: both products and production techniques, but also management methods, the organization of the firm and human resources training. One of the ways by which SMEs can achieve a competitive advantage in manufacturing is through the implementation of Advanced Manufacturing Technology (AMT). An increasing number of them have chosen and are choosing various levels of AMT as the solution. Realizing the importance of SMEs, an attempt has been made in this paper to review the application of AMT in SMEs. Also, a framework has been offered for the implementation of AMT in SMEs. Finally, a summary of findings and conclusions are presented

Advancing automation and robotics technology for the Space Station and for the US economy. Volume 1: Executive overview

In response to Public Law 98-371, dated July 18, 1984, the NASA Advanced Technology Advisory Committee has studied automation and robotics for use in the Space Station. The Executive Overview, Volume 1 presents the major findings of the study and recommends to NASA principles for advancing automation and robotics technologies for the benefit of the Space Station and of the U.S. economy in general. As a result of its study, the Advanced Technology Advisory Committee believes that a key element of technology for the Space Station is extensive use of advanced general-purpose automation and robotics. These systems could provide the United States with important new methods of generating and exploiting space knowledge in commercial enterprises and thereby help preserve U.S. leadership in space

An improved cell controller for the aerospace manufacturing

The aerospace manufacturing industry is unique in that production typically focuses on high variety and quality but low volume. Existing flexible manufacturing cells are limited to certain types of machines, robots and cells which makes it difficult to introduce any changes. In this paper idea of treating machines, robots, any hardware and software as resource has been introduced. It describes the development of the Flexa Cell Coordinator (FCC), a system that is providing a solution to manage cells and their resources in a new flexible manner. It can control, organise and coordinate between cells and resources and is capable of controlling remote cells because of its distributed nature. It also provides connectivity with company systems e.g., Enterprise Resource Planner (ERP). It is extendable and capable of adding multiple cells inside the system. In FCC resources (e.g., tracker) can also be shared between cells. The paper presents its development and results of initial successful testing

Implementing total productive maintenance in Nigerian manufacturing industries

Remarkable improvements have occurred recently in the maintenance management of physical assets and productive systems, so that less wastages of energy and resources occur. The requirement for optimal preventive maintenance using, for instance, justin-time (JIT) and total quality-management (TQM) techniques has given rise to whathas been called the total productive-maintenance (TPM) approach. This study explores the ways in which Nigerian manufacturing industries can implement TPM as a strategy and culture for improving its performance and suggests self-auditing and bench-marking as desirable prerequisites before TPM implementation