Shape analysis of a parametric human lens model based on geometrical constraints

Abstract

Several simple models, such as conicoid models, are usually adopted to describe the surfaces of the human crystalline lens; unfortunately they do not provide a continuous junction between the anterior and the posterior surface of the lens and then they cannot qualify for biomechanical simulation. Vice versa, more complex mathematical models give a continuous junction between the anterior and the posterior surface, but do not provide a geometrical or optical interpretation of the coefficients of the model. In this work we propose a continuous curvature lens model in which the coefficients are derived by geometrical constraints. In this way, both the continuity in the junction zone and a geometrical-physical interpretation of the coefficient involved in the model are obtained. Shape, volume and curvature of the proposed model were compared with four models presented in the literature: two independent conic equations, two interdependent figuring conicoid equations, conic patches model and modulated hyperbolic cosine.

New Methodology for Diagnosis of Orthopedic Diseases through Additive Manufacturing Models

“…Proximal epiphysis: The pin was placed in the same location of the male of the central portion (X = -11, Y = -8, Z = 83) ( Figure 23). As a result, the male part of the link was built on the lower segment, while the female was on the upper segment, both similar to what already seen [8][9][10].…”

Developing Innovative Crutch Using IDeS (Industrial Design Structure) Methodology

“…It would be very important to analyze the product through a physical prototyping using Additive Manufacturing [16][17][18][19][20]. Then, relying upon the initial budget hypothesis to carry out a cost analysis, in order to understand what the cost of the product could be and a possible sale price.…”

“…Comparing the final product with the objectives initially set, an innovation has been certainly brought with regards to the tip, in terms of shape, materials, cushioning and technology; in fact, there are actually no crutches on the market connected to an application that can expand and improve the experience with them, and this was possible thanks to the load sensors placed in the tip. It would be very important to analyze the product through a physical prototyping using Additive Manufacturing [16][17][18][19][20]. Then, relying upon the initial budget hypothesis to carry out a cost analysis, in order to understand what the cost of the product could be and a possible sale price.…”