Model Analysis

Figure 3. Front view of the crank shaft mechanism.

The main focus of my kinematic analysis was the head of the Peek-a Bear model. In order to to this, I first required to convert the three-dimensional mechanism inside of the model into a planar mechanism. I theorized the mechanism inside could be easily approximated and modeled as an off-set crank slider.

The off-sett crank slider (shown on the right) position, linear velocity, and linear acceleration can be solved by using the equations from Designs of Machinery (attached below).

Theta2 is our input angle and makes a full revolution in respect to the global system in figure 4. In order to correct for this, I subtracted 90 degrees from theta2 in order to establish the horizontal as the point of reference in terms of distance, linear velocity, and linear acceleration.

Figure 4. Side View of Crank Shaft The Mechanism (modeled as a slider crank).