Brian Henson

Conceptual design evaluation using interval type-2 fuzzy information axiom

Concept selection is the most critical part of the design process as it determines the direction of subsequent design stages. In addition, it is a difficult task because available information for decision-making at this stage is imprecise and subjective. This necessitates the need for fuzzy decision models for selecting the best conceptual design among a set of alternatives. Although ordinary fuzzy sets cover uncertainties of linguistic words to some extent, it is recommended to use interval type-2 fuzzy sets (IT2FS) to capture potential uncertainties of words. This paper presents a new concept selection methodology that extends the fuzzy information axiom (FIA) approach to incorporate IT2FSs. The proposed methodology is called interval-type-2 fuzzy information axiom (IT2-FIA). IT2-FIA method is also enriched by using ordered weighted geometric aggregation operator to include the decision makers attitude during the aggregation process. A case study is given to demonstrate the potential of the methodology.

A multiple stakeholders' approach to strategic selection decisions

This paper presents a decision support methodology for strategic selection decisions, in which a single choice has to be made between a number of alternatives in the presence of multiple stakeholders. The methodology uses a combination of Analytic Hierarchy Process (AHP) and Zero-One Goal Programming (ZOGP) to address not only the selection problem from the point of view of an individual stakeholder but also from that of multiple stakeholders, by aggregating different outcomes obtained by the stakeholders. The methodology then can simultaneously account for: minimisation of undesirable intangible and tangible criteria; resource limitations and goal constraints; the view of more than one stakeholder; and it can suggest a single, aggregated, go or no-go decision.

Affective Consumer Requirements: A Case Study of Moisturizer Packaging:

Tools for eliciting and managing product requirements are now well-established in some fields of engineering. These tools primarily focus on linking objective, functional customer requirements to the product’s properties. Whilst there have been advances in identifying human factors requirements, the elicitation of the customers’ subjective requirements of a product remains a challenge. This article reports a comprehensive case study in the use of affective engineering to elicit the subjective requirements for moisturizer packaging. The methodology uses focus groups and surveys to elicit subjective requirements. The results of semantic questionnaires are reduced using principal components analysis to translate the subjective requirements into values for physical properties of the packaging. The resulting requirements for surface textures, shape, and color were validated using questionnaire responses to prototype packaging. The study highlights research issues associated with recombining stimuli that have been tested separately.

A novel tactile sensation measurement system for qualifying touch perception.

Abstract The feel of films, wrapping paper, cardboards, and other packaging materials are important to the commercial success of foods. It is known from peoples self-report studies that different surfaces provoke different subjective responses. There are several mechanical parameters, including friction, roughness, compliance, and thermal properties, which are important to the sensory feel. This paper describes the design, construction, and use of a multi-sensory measurement system for tactile sensation that can be used to evaluate the feel of different packaging materials. The experiments were conducted by sliding or pressing an artificial fingertip with embedded sensors against the surfaces of different samples which were fixed on a force table. The roughness, friction coefficients, compliance, and rate of change in the temperature were obtained. Forty volunteers were asked to touch and rate the samples by filling in questionnaires about how they felt. Strong correlations were found between peoples feelings and the physical measurements.

Kansei Engineering Toolkit for the Packaging Industry

Purpose – The purpose of this paper is to describe the Kansei engineering toolkit that has been developed to provide a set of tools and techniques to support better packaging design.Design/methodology/approach – The toolkit has its foundations in Kansei engineering but the work has extended the scope and increased reliability of results by: including structured linkages to designers; replacing “highest level Kansei” from Kansei type 1 with brand values; introducing a more structured process for the elicitation of type 2 selection of pack physical properties; reducing the complexity of the semantic differential survey used to elicit consumer perceptions; and structuring a process for selection of the Kansei words.Findings – The work has shown that the proposed toolkit is able to support the design of packaging by illustrating the process with industrial case studies.Research limitations/implications – Kansei engineering and the techniques presented in this toolkit are inevitably simplifications of the real...

The impact of affective design of product packaging upon consumer purchase decisions

Affective design aims to create a product that has expected levels of functionality and usability but, additionally offers the user a positive emotional experience. Some success has been achieved by using the Kansei engineering approach but this has not been explicitly applied to packaging design.This paper reports on the first stages of an Affective Packaging Design research programme and presents the result of experiments that explore the relationships between consumer selection and packaging shape using a combination of questionnaires, focus groups and the semantic differential technique. The stimuli for the experiment were examples of confectionery packaging.Results will be presented which indicate relationships between confectionery packaging shape and recipient demographic profile. It is concluded that to inform the design process the study it is important to consider the whole purchase experience, for example, product purchaser, product user and purchase reasons.

Predicting the Effect of Surface Texture on the Qualitative Form of Prehension

Reach-to-grasp movements change quantitatively in a lawful (i.e. predictable) manner with changes in object properties. We explored whether altering object texture would produce qualitative changes in the form of the precontact movement patterns. Twelve participants reached to lift objects from a tabletop. Nine objects were produced, each with one of three grip surface textures (high-friction, medium-friction and low-friction) and one of three widths (50 mm, 70 mm and 90 mm). Each object was placed at three distances (100 mm, 300 mm and 500 mm), representing a total of 27 trial conditions. We observed two distinct movement patterns across all trials—participants either: (i) brought their arm to a stop, secured the object and lifted it from the tabletop; or (ii) grasped the object ‘on-the-fly’, so it was secured in the hand while the arm was moving. A majority of grasps were on-the-fly when the texture was high-friction and none when the object was low-friction, with medium-friction producing an intermediate proportion. Previous research has shown that the probability of on-the-fly behaviour is a function of grasp surface accuracy constraints. A finger friction rig was used to calculate the coefficients of friction for the objects and these calculations showed that the area available for a stable grasp (the ‘functional grasp surface size’) increased with surface friction coefficient. Thus, knowledge of functional grasp surface size is required to predict the probability of observing a given qualitative form of grasping in human prehensile behaviour.

Measuring affective responses for human-oriented product design using the Rasch model

Contrasting adjectives have been a common approach for measuring affective responses to products and to design elements, but this approach has often introduced various sources of inaccuracy. Such inaccuracies yield non-linear scales and their statistical procedures can present shortcomings. A different approach is to use the Rasch model. The application of the Rasch model as a measurement approach for affective responses to design features is novel. Thus, this research aimed to determine whether data from affective responses to some products fit the model. A diverse group of participants assessed the specialness of four pieces of wrapped confectionery. A pool of items from a prior study in the UK division of an international confectionery company was used and the responses were analysed using the model. The outcomes indicated that the application of the Rasch model might overcome some of the limitations of using contrasting adjective pairs to elicit consumers’ affective responses.

Electrotactile touch surface by using transparent graphene

In this work we present a flexible Electrostatic Tactile (ET) surface/display realized by using new emerging material graphene. The graphene is transparent conductor which successfully replaces previous solution based on indium-thin oxide (ITO) and delivers more reliable solution for flexible and bendable displays. The electrostatic tactile surface is capable of delivering programmable, location specific tactile textures. The ET device has an area of 25 cm2, and consists of 130 μm thin optically transparent (>76%) and mechanically flexible structure overlaid unobtrusively on top of a display. The ET system exploits electro vibration phenomena to enable on-demand control of the frictional force between the users fingertip and the device surface. The ET device is integrated through a controller on a mobile display platform to generate fully programmable range of stimulating signals. The ET haptic feedback is formed in accordance with the visual information displayed underneath, with the magnitude and pattern of the frictional force correlated with both the images and the coordinates of the actual touch in real time forming virtual textures on the display surface (haptic virtual silhouette). To quantify rate of change in friction force we performed a dynamic friction coefficient measurement with a system involving an artificial finger mimicking the actual touch. During operation, the dynamic friction between the ET surface and an artificial finger stimulation increases by 26% when the load is 0.8 N and by 24% when the load is 1 N.

Grasping the changes seen in older adults when reaching for objects of varied texture.

Old age is associated with reduced mobility of the hand. To investigate age related decline when reaching-to-lift an object we used sophisticated kinematic apparatus to record reaches carried out by healthy older and younger participants. Three objects of different widths were placed at three different distances, with objects having either a high or low friction surface (i.e. rough or slippery). Older participants showed quantitative differences to their younger counterparts – movements were slower and peak speed did not scale with object distance. There were also qualitative differences with older adults showing a greater propensity to stop the hand and adjust finger position before lifting objects. The older participants particularly struggled to lift wide slippery objects, apparently due to an inability to manipulate their grasp to provide the level of precision necessary to functionally enclose the object. These data shed light on the nature of age related changes in reaching-to-grasp movements and establish a powerful technique for exploring how different product designs will impact on prehensile behavior.