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The purpose of this paper is to determine the most‐practical means of transforming computer‐aided‐design models of custom clubfoot pedorthoses into functional pedorthoses for testing on patients in a clinical trial.

The materials used in conventional orthosis fabrication are not yet available for solid free‐form fabrication; therefore, to fabricate the pedorthoses, several approaches were considered, including direct manufacturing, additive‐based moulding, laser cutting of foam and combinations of several of these approaches.

The chosen approach of additively manufacturing the custom hard shell, and moulding the polyurethane‐foam insert, resulted in accurate, durable and effective pedorthoses that fit well, and could be adjusted as needed. The pedorthoses that were produced are currently being tested on the respective patients for their improvement in mobility and degree of clubfoot correction, and will continue through early 2010.

Additive manufacturing provides an ideal approach for generating the custom, end‐use hard‐ and soft‐layer patterns: each pedorthosis is truly unique; and the soft layer has regions of variable thickness. The advantage of this approach is the reduction in labour and the increase in degrees of design freedom available, compared to conventional methods of fabricating orthotic devices. Replacement inserts can be moulded in a matter of hours using this silicone‐moulding approach.

Several new approaches for fabricating custom orthotic devices were explored, and the related results are discussed. The goal of this paper is to convey the potential of the fabrication procedure used and lessons learned on this project to the rapid prototyping and orthotic communities.

The purpose of this study is to provide some references about applying the semi-active particle damper to enhance the stability of the pipe structure.

This paper establishes the dynamical models of semi-active particle damper based on traditional dynamical theory and fractional-order theory, respectively. The semi-active particle damping vibration isolation system applied in a pipe structure is proposed, and its analytical solution compared with G-L numerical solution is solved by the averaging method. The quantitative relationships of fractional-order parameters (a and kp) are confirmed and their influences on the amplitude-frequency response of the vibration isolation system are analyzed. A fixed point can be obtained from the amplitude-frequency response curve, and the optimal parameter used for improving the vibration reduction effect of semi-active particle damper can be calculated based on this point. The nonlinear phenomenon caused by nonlinear oscillators is also investigated.

The results show that the nonlinear stiffness parameter p will cause the jump phenomenon while p is close to 87; with the variation of nonlinear damping parameter μ, the pitchfork bifurcation phenomenon will occur with an unstable branch after the transient response; with the change of fractional-order coefficient k_p, a segmented bifurcation phenomenon will happen, where an interval that k_p between 18.5 and 21.5 has no bifurcation phenomenon.

This study establishes a mathematical model of the typical semi-active particle damping vibration isolation system according to fractional-order theory and researches its nonlinear characteristics.