An approach to automatic foot measurement using 3D scanned data is proposed in this paper. The proposed approach was evaluated through comparisons of simulated measurements (SM) of eleven male and nine female participants with manual measurements and with the output of a commercially available automated foot measuring system (CP). The registration procedure for the measurements and unambiguous definitions for each measurement were first established. Eighteen dimensions of each foot were calculated from the scanned data that comprised point clouds and selected landmarks. Two operators manually measured each participant's foot twice. These manual measurements (MM) showed high inter-and intra-operator reliability (ICC>0.84). Ten of the eighteen dimensions obtained from the three measurement methods, SM, CP, and MM, were subjected to an ANOVA and eight of the measurements showed significant differences among the three methods. After establishing a linear correction to adjust for systematic errors, there were no significant differences between the SM and MM methods for 17 of the 18 foot dimensions; and the single exception was the heel width dimension. The differences among the three methods, correction procedures and their significance are discussed.Relevance to industry: Measuring feet to obtain the relevant dimensions that characterize feet can be quite tedious and the measurement may be dependent on the 2 measurer. Automatic measurement with scanned data on the other hand, can give replicable information even though the measurements depend on the intricacies of the scanning system and the computational algorithms adopted. The proposed definitions and algorithms provide a means to automate foot measurements for customized footwear.

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Footwear comfort is primarily determined by the fit between the foot and the shoe. Foot deformations that cannot be accommodated by the flexibility of the material of the shoe upper have to be dealt with by other adaptive means. The major purpose of this study was to determine foot deformations using nine foot dimensions-foot length, arch length, foot width, midfoot width, heel width, midfoot height, medial malleolus height of the most protruding point, lateral malleolus height of the most protruding point and ball girth-as well as the eversion/inversion of the foot while bearing weight. Each foot of 30 Hong Kong Chinese adults (15 males and 15 females) was laser scanned under the conditions of no body-weight (NWB), half body-weight (HWB) and full body-weight (FWB). The nine dimensions and foot rotation were determined with a computer program. The results show that the foot became significantly longer, wider, and reduced in height while everting with increased loading on the foot. The midfoot had relatively large changes in width and height when compared to the forefoot and rearfoot. Even though there were no obvious patterns between the left and right foot for both males and females, considerable differences did exist between the two feet of a few participants. Foot length as a percentage of stature changed from 14.94% to 15.10% to 15.13% in males as the load on the foot increased from NWB to HWB to FWB, respectively. These percentages were 14.56%, 14.72%, and 14.77% for females. Even though foot width was significantly correlated with the body weight of males, no such relationship exists in Hong Kong females.

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Although the subjective workload assessment technique (SWAT) has been widely used, it has two main problems: it is not very sensitive for low mental workloads and it requires a time-consuming card sorting pretask procedure. In this study are presented five variations of SWAT in an effort to overcome the limitations. Four of the variants used the continuous SWAT subscales while one used the discrete SWAT subscale. Fifteen subjects participated in the experiment. The scales were compared with the original SWAT scale in terms of sensitivity and pretask procedure completion time when performing arithmetic tasks. The results show that all four variants are more sensitive than the conventional SWAT scale and that the pairwise comparison procedure takes significantly less pretask completion time compared with the original SWAT scale. Thus, the conventional pretask procedure can be replaced by a simple unweighted averaging to yield a scale of high sensitivity.

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The use of pressure sensors made of conductive polymers is common in biomechanical applications. Unfortunately, hysteresis, nonlinearity, non-repeatability and creep have a signi®cant effect on the pressure readings when such conductive polymers are used. The objective of this paper is to explore the potential of a new¯exible encapsulated micro electromechanical system (MEMS) pressure sensor system as an alternative for human interface pressure measurement. A prototype has been designed, fabricated, and characterized. Testing has shown that the proposed packaging approach shows very little degradation in the performance characteristics of the original MEMS pressure sensor. The much-needed characteristics of repeatability, linearity, low hysteresis, temperature independency are preserved. Thus the¯exible encapsulated MEMS pressure sensor system is very promising and shows superiority over the commercially available conductive polymer ®lm sensors for pressure measurement in biomechanical applications.

Footwear cushioning was evaluated objectively using an impact tester and related to perceived levels of cushioning (PLC). To evaluate the perceived levels of cushioning during standing, walking, and running, 3 experiments were conducted with 20 participants in each experiment. A 7-point subjective rating scale was used to rate the perceived levels of cushioning. At the end of the experiment, the subjective perceptions of cushioning were also recorded. During standing and running, the perceived level of cushioning can be predicted from the time to peak deceleration and/or stiffness (or compression). During walking, however, the magnitude of the peak deceleration on the impact tester appears to be a good predictor of PLC. Impact characterizations can reveal important differences between materials and how they are perceived during activity. In addition, the results seem to explain and link the differences that exist in the ergonomics and biomechanics literature on cushioning. Applications of this research include the design and selection of materials for footwear, floor mats, and other supporting surfaces.