Motivation

I have always been interested in how a table fan oscillates back and forth. This seemed really simple, but a quick google search revealed a fascinating mechanism that allows for this oscillation to happen. I therefore took the opportunity in this class to reverse engineer the oscillation mechanism to understand what makes this fan work the work it does.

For this report, videos and pictures were taken which illustrate the reverse engineering process. Moreover, gear teeth and radii were measured to find mechanical advantage values, and kinematic analysis performed. My primary objective was to understand the relationship between θ_input and θ_output. This will be shown as position analysis graph results in the form of the theta_2 from the 4bar mechanism. In addition, velocity analysis and acceleration analysis were performed using the vector loop equations to analyze the fan oscillation also using the four bar mechanism. Also, the handwritten equations and the computer program used for this analyses is provided. So lets dive in!

This report is broken into the following:

1.    Why this was built and did it achieve the mechanism

2.    Reverse engineering process (videos and pictures)

3.    Kinematic analysis

        a. Equations, assumptions and MATLAB code

        b. Results

              i. Position analysis (theta_2)

              ii. Velocity analysis

              III. Acceleration analysis

              iv. Mechanical advantage

With this report, I hope to reveal what a simple, yet elegant, efficient design the table fan is, and how it actually works the way it was intended to.

*Figure numbering restarts for every sub page. Thus, there will be multiple figure 1's, 2's etc, throughout this report corresponding to new figures for every subsequent page in each subheading