Turn-by-wire: Computationally mediated physical fabrication

Advances in digital fabrication have simultaneously created new capabilities while reinforcing outdated workflows that constrain how, and by whom, these fabrication tools are used. In this paper, we investigate how a new class of hybrid-controlled machines can collaborate with novice and expert users alike to yield a more lucid making experience. We demonstrate these ideas through our system, Turn-by-Wire. By combining the capabilities of a traditional lathe with haptic input controllers that modulate both position and force, we detail a series of novel interaction metaphors that invite a more fluid making process spanning digital, model-centric, computer control, and embodied, adaptive, human control. We evaluate our system through a user study and discuss how these concepts generalize to other fabrication tools

Improving the Availability of Manufacturability Information through Decentralization of Process Planning

Process planning is part of the general product development and production process that usually follows design and precedes manufacturing. Manufacturability and process planning information in general play central role in many product development and production activities, including paradoxically, conceptual and detail design - the activities that take place before process planning. The need of conducting some of the process planning activities formally before or during design is thus rather obvious. One of the main research issues is therefore the identification of the process planning activities that can be performed before the traditional process planning phase and handling of the process planning information so as to adequately provide the designers with the manufacturability informationneeded during conceptual and detail design. Another issue is how to support collaboration during process planning and how to maintain continuity of the process planning tasks. This paper suggests the decentralization of the process planning task and proposes the execution of the process planning activities in a piecemeal fashion, starting right afterreceiving an order and specifying the requirements for a product. Process planning under the proposed procedure consists of six semi-autonomous sub-phases, some of which comprise activities that must be conducted prior to the process planning phase. This helps to overcome the problem of timely availability of manufacturability information during the execution of upstream and downstream product development and production activities. The paper alsoproposes a computer-based method of handling the manufacturability information generated in various stages of the product development and production process. A database design and structure of prototype software that manages the process planning information are presented and discussed. Furthermore, a case study conducted to explore howthe proposed process planning procedure could be put in use is presented and discussed

Procedure for the implementation of a virtual CNC lathe

The paper presents a work executed in the virtual prototyping area. It is described as a procedure for the implementation of a CNC (Computerized Numeric Command) lathe prototype using software for virtual environment development. This procedures focus mainly on the interlocking system (functionality) and geometric model (physical design) of the lathe. Consequently, this work aims at checking the potential and limitations of this graphic interface tool, considering the complexity of the data required for product prototyping in manufacturing or assembly.Eje: Programación de imágenesRed de Universidades con Carreras en Informática (RedUNCI

Optimal choice of machine tool for a machining job in a CAE environment

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.Developments in cutting tools, coolants, drives, controls, tool changers, pallet changers and the philosophy of machine tool design have made ground breaking changes in machine tools and machining processes. Modern Machining Centres have been developed to perform several operations on several faces of a workpiece in a single setup. On the other hand industry requires high value added components, which have many quality critical features to be manufactured in an outsourcing environment as opposed to the traditional in-house manufacture. The success of this manufacture critically depends on matching the advanced features of the machine tools to the complexity of the component. This project has developed a methodology to represent the features of a machine tool in the form of an alphanumeric string and the features of the component in another string. The strings are then matched to choose the most suitable and economical Machine Tool for the component’s manufacture. Literature identified that block structure is the way to answer the question ‘how to systematically describe the layout of such a machining centre’. Incomplete attempts to describe a block structure as alphanumeric strings were also presented in the literature. Survey on sales literature from several machine tool suppliers was investigated to systematically identify the features need by the user for the choice of a machine tool. Combining these, a new alphanumeric string was developed to represent machine tools. Using these strings as one of the ‘key’s for sorting a database of machine tools was developed. A supporting database of machine tools was also developed. Survey on machining on the other hand identified, that machining features can be used as a basis for planning the machining of a component. It analysed various features and feature sets proposed and provided and their recognition in CAD models. Though a vast number of features were described only two sets were complete sets. The project was started with one of them, (the other was carrying too many unwanted details for the task of this project) machining features supported by ‘Expert Machinist’ software. But when it became unavailable a ‘Feature set’ along those lines were defined and used in the generation of an alphanumeric string to represent the work. Comparing the two strings led the choice of suitable machines from the database. The methodology is implemented as a bolt on software incorporated within Pro/Engineer software where one can model any given component using cut features (mimicking machining operation) and produce a list of machine tools having features for the machining of that component. This will enable outsourcing companies to identify those Precision Engineers who have the machine tools with the matching apabilities. Supporting software and databases were developed using Access Database, Visual Basic and C with Pro/TOOLKIT functions. The resulting software suite was tested on several case studies and found to be effective

Multi-agent framework based on smart sensors/actuators for machine tools control and monitoring

Throughout the history, the evolutions of the requirements for manufacturing equipments have depended on the changes in the customers' demands. Among the present trends in the requirements for new manufacturing equipments, there are more flexible and more reactive machines. In order to satisfy those requirements, this paper proposes a control and monitoring framework for machine tools based on smart sensor, on smart actuator and on agent concepts. The proposed control and monitoring framework achieves machine monitoring, process monitoring and adapting functions that are not usually provided by machine tool control systems. The proposed control and monitoring framework has been evaluated by the means of a simulated operative part of a machine tool. The communication between the agents is achieved thanks to an Ethernet network and CORBA protocol. The experiments (with and without cooperation between agents for accommodating) give encouraging results for implementing the proposed control framework to operational machines. Also, the cooperation between the agents of control and monitoring framework contributes to the improvement of reactivity by adapting cutting parameters to the machine and process states and to increase productivity

application of process parameters in planning and technological documentation cnc machine tools and cmms programming perspective

Abstract This article focuses on the role and application of process parameters in technological process planning (TPP) and technological documentation (TD). The challenges and complexity involved in computer numerical control (CNC) machine tools and coordinate measuring machines (CMMs) programming have been taken into consideration with reference to the TD. The article presents the use of different programming platforms and implementation of them in technological process planning. The subtractive manufacturing and related measurements that are required during the TPP and TD phase have been taken into consideration. The findings and suggestions enable planners to incorporate the existing programming platforms and tools in the TPP and TD

Manufacturing code generation for rotational parts in a feature based product modelling environment

An important element for the integration of CAD/CAM is the representation and handling of data used during the design and manufacturing activities. The use of features and product modelling techniques bring a better handling of this data and provide CAD/CAM with an excellent platform for integration. The thesis explores the use of a predefined set of features in a product modelling environment for the design and machining of rotational components. Theword features in this research implies a set of functional, geometrical and technological information with a unique form. Those features are pre-defined and comprise of a limited number of elements which carry the information related to design and manufacturing activities. The thesis is divided into three main parts. The first part contains a review of topics related to the research e. g. group technology, component features, CAD/CAM and also contains a literature survey of related research works. In the second part the "features" are defined and presented. Also the product modelling environment is explained and the basic rule based procedures which are used to automatize the operation planning activities are presented. In the last part a description of the case-studies used for automatic NC code generation is presented followed by a discussion of the results. Lastly, the conclusions are drawn and ideas for further work presented

An Early Warning Monitoring System for CNC Spindle Bearing Failure

Equipment employed in a manufacturing environment must be able to operate as long as possible having as little downtime as possible. Therefore, maintenance is crucial in order to allow for the equipment to perform its designated tasks without failure, especially on critical systems. In a CNC machine, if the spindle fails, the machine is useless. Having the ability to detect spindle degradation to the point where a replacement spindle installation can be planned, via condition monitoring, is invaluable to a manufacturer who utilizes these types of machines. An early warning monitoring system for CNC spindle bearing failure has been developed to be utilized directly on a CNC machine\u27s controller employing an open architecture structure. The main system uses an ultrasonic sensor as its primary sensing component and provides a singular value as to the spindle condition. The system allows for both real time data recording as well as provides a trending history for the machine. Additionally, the system allows for the data to be seen remotely via the internet. Accessory devices can be added to perform an in-depth bearing failure analysis. The total system (including accessories) costs just under $2,400, allowing for a very effective system at a very low price. A few thousand dollars towards a predictive and preventive maintenance monitoring solution can prevent tens-of-thousands of dollars in lost production and unnecessary maintenance costs if the system is utilized as intended. System performance was tested to investigate sensor measurement applicability. Spindle speed was found to have an effect on the sensor\u27s output, however excessive vibration did not. Therefore, the same spindle speed must be used each time a measurement is taken. Measurements while the machine is cutting can be performed, however, a test mode is recommended for the most accurate results. The amount of variation for an in-process reading was found to be lower for a harder material (ie: steel vs. aluminum), for the same spindle speed and depth of cut. The system was tested to see if it could detect the various stages of bearing failure. It was unable to detect a plastic/resin bearing cage degradation failure until it was too late as the failure was too quiet to detect

OPTIMIZATION OF CUTTING CONDITIONS FOR SUSTAINABLE MACHINING OF SINTERED POWDER METAL STEELS USING PCBN AND CARBIDE TOOLS

Powder metals are becoming a popular choice in the automotive and other manufacturing industries because of their ability to meet wide ranging product functional requirements without compromising the performance of the product. They offer various advantages, including weight reduction, near net-shape processing capability, and their ability to be sintered to achieve desired properties in the end-product. However, in order to satisfy the product design requirements during manufacturing, they need to be machined to the required tolerances. Machining of powder metals is quite different to machining of traditional metals because of their specific properties, including porosity. This thesis work deals with the finish machining of powder metal steels in automotive applications, for increased tool-life/reduced tool-wear. Tool-life is affected by a variety of factors such as tool grade selection, tool coating, cutting conditions and tool geometry including cutting edge geometry. This work involves optimization of cutting conditions for plunge cutting and boring operations of automotive powder metal components using PCBN and carbide tools. The cycle time of the process introduces an additional constraint for the optimization model along with the tool-wear criterion. Optimized cutting conditions are achieved for maximum tool-life