Synthesizing desigji

CAD with FEA is a powerful tool in effectively synthesizing a mechanical system design into an optimized product. A few of these are reviewed. With the dynamic analysis method one combines motion with forces in a mechanical system to calculate positions, velocities, accelerations, and reaction forces on parts in the system. The analysis is performed stepwise within a given interval of time. Each degree of freedom is associated with a specific coordinate for which initial position and velocity must be supplied.

The computer model from which the design is analyzed creates by defining the system in various ways. Generally, data relating to individual parts, the user must supply joints, forces, and overall system coordination, either direcdy or through a manipulation of data within the software. The results of all of these methods of analyses are typically available in many forms, depending on the needs of the designer. As an example the kinematic analysis and synthesis method studies the motion or position of a set of rigid bodies in a system without reference to the forces causing that motion or the mass of the bodies. It allows engineers to sec how the mechanisms they design will function in motion.

This approach gives the designer the ability to avoid faulty designs and also to apply the design to a variety of approaches without constructing a physical prototype. Synthesis of the data extracted from kinematic analysis in numerous approaches of the design process leads to optimization of the design. The increased number of trials that kinematic analysis allows the mechanical engineer to perform will provide results in optimizing the behavior of the resulting product before actual production.

There is the static analysis method that determines reaction forces at the attachment positions of resting mechanisms when a constant load is applied. As long as zero velocity is assumed, static analysis can be performed on mechanisms at different points of their range of motion. Static analysis allows the designer to determine the reaction forces on whole mechanical systems as well as interconnection forces transmitted to their individual joints. The data extracted from static analysis can be useful in determining compatibility with the various criteria set out in the problem definition. These criteria may include reliability, fatigue, and performance considerations to be analyzed through stress analysis methods.

With the experimental analysis one involves fabricating a prototype and subjecting it to various experimental test methods. Although this usually takes place in the later stages of design, CAD systems enable the designer to make more effective use of experimental data, especially where analytical methods are thought to be unreliable for the given model. CAD also provides a useful platform for incorporating experimental results into the design process when experimental analysis is performed in earlier approaches of the process.

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