Peek-a-Bevo is a one degree of freedom, six-bar mechanism. Analysis of this mechanism uses the input Theta 2, which is the positive angle from the x-axis of the outside crank (Link 2), which has freedom to rotate 360°. Link 2, rotating in one complete cycle, moves Bevo’s head and arms through the motion of uncovering and hiding his eyes. My analysis aims to describe the position of Bevo’s head and hands to quantitatively describe the peek-a-boo movement propagated by this device.
A four-bar crank-slider mechanism was used to model the behavior of this device because the kinematic analysis of six-bar mechanisms is beyond the scope of this class, and the top two links have limited impact on the output motion and can be ignored. Additionally, the joint connecting Link 3 and Link 4 is restricted to vertical motion. This restriction was found by inspection of the physical device and simplifies the motion to two dependent variables, and allows for me to solve the position analysis.
