Glen Mullineux

Introducing Loading Uncertainty in Topology Optimization

Uncertainty is an important consideration in structural design and optimization to produce robust and reliable solutions. This paper introduces an efficient and accurate approach to robust structural topology optimization. The objective is to minimize expected compliance with uncertainty in loading magnitude and applied direction, where uncertainties are assumed normally distributed and statistically independent. This new approach is analogous to a multiple load case problem where load cases and weights are derived analytically to accurately and efficiently compute expected compliance and sensitivities. Illustrative examples using a level-set-based topology optimization method are then used to demonstrate the proposed approach.

Late customisation: issues of mass customisation in the food industry

The strategy of mass customisation is being increasingly adopted as companies seek to exploit market trends for greater product variety and individualisation. The implications of changing to mass customisation practice are considerable, where traditional contradictions of high volume and extensive product variety require being reconciled. The literature discusses the need for an integrated approach to mass customisation across all business functions if micro-segmentation of markets is to be profitably pursued, and the current paper investigates extending the paradigm of mass customisation into the, until now, poorly represented sector of food processing. Product design and manufacturing system design for mass customisation are reviewed and contrasted with good practice in more traditional mass customisation industries.

Constraint-based approach to investigate the process flexibility of food processing equipment

Over the last decade the UK food processing industry has become increasing competitive. This leads the sector to maintain high numbers of product variations. Although some of these products are stable over long periods, others are short lived or seasonal. The ability to handle both the complexity of process and large variations in product format creates extreme difficulties in ensuring that the existing manufacturing, handling and packaging equipment has the process flexibility to cope. This paper presents an approach for investigating the performance envelopes of machines utilizing a constraint modelling environment. The approach aims to provide the engineer with enhanced understanding of the range of functionality of a given machine and provides the possibility of redesign to process variant product.

The representation and handling of constraints for the design, analysis, and optimization of high speed machinery

High speed machinery has played and continues to play a vital role in the manufacture and production of consumer goods. In the design of high speed systems there are two key considerations: power transmission and motion control. Although there is considerable computer-based support for the design of systems to achieve requirements of power transmission, there is only limited support for the design of systems to deliver complex motion control. This is particularly the case where mechanism and linkage systems are considered in order to achieve large displacements and intricate paths involving reentrant and reciprocating components. One explanation for this relative lack of supportive tools is the underlying reasoning and analysis techniques implemented within many commercial and research software environments. To overcome these limitations a constraint-based approach has been employed to provide the fundamental elements of a design environment for mechanisms and machine systems. The design environment provides support for the transition from concept to embodiment stages of the design process and the subsequent stages of detailed design and optimization. In contrast to many research approaches the design environment presented in this paper has been created and developed through close collaboration with industry and through extensive application to real design scenarios. First, the underlying representations and methods are presented. The fundamental elements of the design environment are then described and its capabilities discussed with particular reference to the use of constraints in design.

The Integration of Coordinate Measuring Machines within a Design and Manufacturing Environment

The role of the coordinate measuring machine within the inspection process has changed throughout its brief development. With its integration with industrial computer aided design (CAD) systems, its role is to change yet again. This paper presents the difficulties and limitations of current practice and identifies the inputs and decisions that need to be made within an integrated manufacturing environment. A research programme was undertaken to investigate an approach based upon intelligent communications between systems. This led to the creation of a demonstration system that was employed in the measurement of industrial components. A case study, using a standard test block, is included to illustrate the processes undertaken. This includes feature identification, probe calibration and selection strategies and automatic re-routing to minimize changes in probes and orientations. It is proposed that the approach demonstrated can be incorporated within a concurrent engineering environment to provide feedback and information about machine adjustments through a constraint modelling process.

Finite element simulation of folding carton erection failure

Abstract In response to recent European Union (EU) regulations on packaging waste, the packaging industry requires greater fundamental understanding of the machine-material interactions that take place during packaging operations. Such an understanding is necessary to handle thinner lighter-weight materials, specify the material properties required for successful processing and design right-first-time machinery. The folding carton industry, in particular, has been affected by the new legislation and needs to realize the potential of computational tools for simulating the behaviour of packaging materials and generating the necessary understanding. This paper describes the creation and validation of a detailed finite element model of a carton during a common packaging operation. The model is applied here to address the problem of carton buckling. The carton was modelled using a linear elastic material definition with non-linear crease behaviour. Air inrush suction, which is believed to cause buckling, was quantified experimentally and incorporated using contact damping interactions. The results of the simulation are validated against high-speed video of carton production. The model successfully predicts the pattern of deformation of the carton during buckling and its increasing magnitude with production rate. The model can be applied to study the effects of variation in material properties, pack properties and machine settings. Such studies will improve responsiveness to change and will ultimately allow end-users to use thinner, lighter-weight materials in accordance with the EU regulations.

Simulating the behaviour of folded cartons during complex packing operations

Abstract The folding carton is a widely used packaging solution. Recent European Union packaging legislation has forced carton manufacturers to use lighter-weight grades of carton board. This typically results in a reduction in board stiffness, which can lead to decreased process efficacy or even prevent successful processing. In order to overcome this, end-users lower production rates and fine-tune packaging machine settings for each pack and material. This trial-and-error approach is necessary because the rules relating machine set-up to pack design and material properties are not generally well known. The present study addresses this fundamental issue through the creation of a finite-element computer simulation of carton processing. Mechanical testing was performed to ascertain the key mechanical properties of the carton walls and creases. The carton model was validated against the experimental results and was then subjected to the machine-material interactions that take place during complex packaging operations. The overall approach was validated and the simulation showed good agreement with the physical system. The results of the simulation can be used to determine guidelines relating machine set-up criteria to carton properties. This will improve responsiveness to change and will ultimately allow end-users to process thinner lighter-weight materials more effectively.

An Information Support Approach for Machine Design & Building Companies:

The recording of information regarding machine function, performance, and failure, which is generated during the machine development, commissioning, and service is vital to an organization. Previous research has shown this information is often poorly recorded or even missed during these critical stages. The work presented in this article offers a solution based on the core product model, offering the potential to be revisit and retrieved the information throughout the product life cycle and into any next iteration of the design. An industrial case study presenting the operation of the approach is presented.

A constraint-net approach to the resolution of conflicts in a product with multi-technology requirements

While many procedures exist to support the systematic development of a product, it is often difficult to create an environment in which the early stages of the design are resolved. This can particularly happen when the product design is based upon a wide range of technologies and the expert members of the design team are drawn from many disciplines. The constraint resolution approach allows the requirements to be formed into rules and their combined truth established. Within such an environment an investigation has been undertaken to determine the possibility of establishing clusters of rules relating to individual technical aspects of the design requirements, which are then formed into networks that can be solved interactively within the constraint modelling environment. This paper draws upon the experience of designing a disposable cell counting device for medical applications and illustrates its adaptation to other applications through the use of the derived constraint-net.

A reconfigurable robotic folding system for confectionery industry

Purpose - This paper aims to investigate reconfigurable technology using robotic technology for folding carton in confectionery industry. Design/methodology/approach - Based on the analysis of common motion and manipulation, modules such as robotic fingers and robotic folders are explored and designed. A robotic system is then constructed by arranging those modules for diverse cartons. Findings - A prototyped test rig shows the adaptability of the robotic system. The reconfigurability of the robotic system is realized and verified by experiments and an industrial demonstrator. Practical implications - This research leads to the development of a demonstrator, manufactured and controlled by industries, to further commercial exploitation of this robotic system. It has been applied in a strict industry environment for a chocolate manufacturer. Originality/value - This robotic system applied successfully the theory of reconfigurability by using modularity in packaging systems into confectionery industry.