Abstract:

Teaching engineering design in the early phases, especially in the sophomore or junior years can be very challenging. It is difficult to mimic the industrial setting to leap from concept to prototype to product in a classroom environment. By presenting a real world problem that has a potential demand, it is possible to emulate the design steps carried out in the industry. In-class design consisting of paper design and computer simulation lacks the final stage, and most rewarding, of a physical product. Introducing prototyping can facilitate a stage in design where a physical product is necessary for better conceptual understanding, clearer visualization and realization of the specialized problems.

The objective of this paper is to present a method that provides motivation in teaching project design through 3-D prototyping. The progression of a heart valve design is described along with the modeling capabilities and its possible benefits in the classroom.

Rapid prototyping is the fabrication of physical objects from 3-D virtual images in a digital data set. This technology is used to make models and prototype parts for desired applications in many fields. In most projects, a designer has to conceptualize and analyze different versions of the product to be made. Selective versions of the design are then replicated on a computer using computer aided design (CAD) programs such as SolidWorks, AutoCAD, or Maya. After the design is made on the computer, the corresponding data is transferred into a 3-D printing machine where a physical model is made. Models can be made out of an ABS-type substance which can be hardened to yield good prototypes. Other materials that can be used are plastic, rubber, or metal. In addition, it is possible to enhance the appearance of the prototype by adding coloring to give it a more real and life-like appearance.

In this project a heart valve is designed using an iterative approach to rapid prototyping technology. Valvular heart disease affects about one in fifty people, a serious condition that can be treated by valve replacement. It is one of the contributing problems to cardiovascular disease, the leading cause of death in the world.

The first step in designing a heart valve included researching current solutions and methods and new studies of the heart valve. Using this information numerous models were made using SolidWorks with varying properties but only two were selected for test purposes. Upon design reviews some of the problems became obvious and improvements were made. New 3-D prototypes are being designed to alleviate the problems observed.

This process in a classroom setting will give the students a better appreciation of a real part and the difference between conceptual design and physical design. The heart valve models will be used for educational purposes, and refines models will be used for laboratory experimental testing giving better insight into designing improved artificial heart valves.