Planning and control of a hybrid vacuum-forming system based on screw-pin tooling

This paper introduced planning and control of a hybrid vacuum-forming machine system (HAVES). The HAVES was developed to integrate CAD/CAM, screw-pin tooling, CNC, vacuum forming and optical measurement device together to produce vacuum forming components. The screw-pin tooling was employed to replace traditional dedicated solid tooling and its reconfigurability provided the HAVES with advantages in rapid producing small batch and mass customization products. The whole control system of the HAVES is divided into two parts: one for screw-pin tooling adjustment and machining by using CNC control, and the other for vacuum forming by using PLC control. The detail design of the control system was discussed

A framework to support multiple perspectives in eco-efficiency decisions

Increasingly, it is recognised that human activity is causing our environment to degrade, and that there is a very real danger of doing irreversible damage to natural systems of which we have only a partial understanding. Neither living in, nor doing business in a future world with a degraded environment is desirable, and individuals and businesses alike are increasingly seeking ways to operate on a more sustainable basis. Sustainability was defined by WCED [1] as “meeting the needs of the present without compromising the ability of future generations to meet their own needs” – but how can this aspiration be translated into specific decisions and actions? This paper describes some of the difficulties that must be overcome in the creation of a decision-support framework for eco-efficiency decisions, in order to ensure that we are targeting the right problems

A framework to support multiple perspectives in eco-efficiency decisions

Increasingly, it is recognised that human activity is causing our environment to degrade, and that there is a very real danger of doing irreversible damage to natural systems of which we have only a partial understanding. Neither living in, nor doing business in a future world with a degraded environment is desirable, and individuals and businesses alike are increasingly seeking ways to operate on a more sustainable basis. Sustainability was defined by WCED [1] as “meeting the needs of the present without compromising the ability of future generations to meet their own needs” – but how can this aspiration be translated into specific decisions and actions? This paper describes some of the difficulties that must be overcome in the creation of a decision-support framework for eco-efficiency decisions, in order to ensure that we are targeting the right problems

Machining characteristics of polymers

novembre 19971997/11 (N423)

Polyamide 66 microspheres metallised with in situ synthesised gold nanoparticles for a catalytic application

A simple concept is proposed to metallise polyamide 66 (PA66) spherulite structures with in situ synthesised gold nanoparticles (Au NPs) using a wet chemical method. This cost-effective approach, applied to produce a PA66/Au NP hybrid material, offers the advantages of controlling the nanoparticle size, the size distribution and the organic-inorganic interactions. These are the key factors that have to be controlled to construct consistent Au nanostructures which are essential for producing the catalytic activities of interest. The hybrid materials obtained are characterised by means of scanning electron microscopy, transmission electron microscopy, attenuated total reflection-Fourier transform infrared spectrometry and X-ray diffraction spectrometry. The results show that PA66 microspheres obtained via the crystallisation process are coated with Au NPs of 13 nm in size. It was found that controlling the metal coordination is the key parameter to template the Au NPs on the spherulite surfaces. The preparation processes and the key factors leading to the formation of PA66 spherulites coated with Au NPs are discussed. Moreover, the efficiency of the coated spherulites as a potential catalyst is proved by demonstrating the reduction of methylene blue via UV-visible spectrometry

An investigation into minimising total energy consumption and total weighted tardiness in job shops

Manufacturing enterprises nowadays face the challenge of increasing energy prices and requirements to reduce their emissions. Most reported work on reducing manufacturing energy consumption today focuses on the need to improve the efficiency of resources (machines) largely ignoring the potential for energy reducing on the system-level where the operational method can be employed as the energy saving approach. The advantage is clearly that the scheduling and planning approach can also be applied across existing legacy systems and does not require large investment. Therefore, a multi-objective scheduling method is developed in this paper with reducing energy consumption as one of the objectives. This research focuses on classical job shop environment which is widely used in the manufacturing industry. A model for the bi-objectives problem that minimises total electricity consumption and total weighted tardiness is developed and the Non-dominant Sorting Genetic Algorithm is employed as the solution to obtain the Pareto front. A case study based on a modified 10 × 10 job shop is presented to show the effectiveness of the algorithm and to prove the feasibility of the model

Investigation of Glucose Non-Invasive Measurement Based on NIR Laser

Near-infrared (NIR) diffuse reflectance spectroscopy represents a feasible and promising approach to the noninvasive prediction of blood glucose concentration. This paper experimentally studied and proposed a novel method to develop a stand-alone measurement system, in which laser beams at several particular wavelengths are collimated and illuminated a sample with low-energy NIR by an optical fibre probe, and the diffused reflectance from the sample is collected by a detector. The experimental scheme of the measurement system has been demonstrated to be reasonable and suitable for detecting the change of diffuse reflected absorbance from phantoms and finger tissue. The experimental results have presented the good correlation between the diffuse reflected absorbance and glucose concentration at several particular wavelengths. The spectra lines are perfectly separate from each other at different glucose concentration in vitro. Obvious differences exist in the diffuse reflected absorbance for different glucose concentration. According to the testing standard of the Oral Glucose Tolerance Test (OGTT), the dynamic changes, which the diffuse reflected absorbance from tissue is accompanied with the change of the glucose concentration, have been explored by taking a certain amount oral glucose solution. The results have presented that the sensing system proposed is already able to sense the glucose change from fingertip tissue though the overlapping spectra are encountered. Also, the temperature effect of the sample on the diffuse reflected absorbance of the glucose has been taken into consideration

Performance evaluation of conformable vices

This paper introduces an experimental design and evaluation of two newly developed conformable vices. One conformable vice is sheet metal vice and the other is ball bearing vice, these two conformable vices are designed for holding complex-shaped components. The experimental investigation is performed by comparing the conformable vices against a standard vice in static performance and machining performance. Force signals are monitored during experiments. From the comparison, the performance of the two conformable vices is discussed. The results prove that the two conformable vices can be applied for clamping components with performance comparable with a standard vice