The main mechanism consists of the crank and the two links inside the base and the bear's body. This mechanism drives the arm and the head movement.
Figure 1: Motion of the Main Mechanism
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Both links can be modeled as a slotted link with the physical slots being grounded pins on which the links rotate and slide.
By solving the loop equation for the first part of the mechanism we get 2 equations to define the rotation θ3 and length of b1.
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Matlab outputs the following for the angle theta3 θ3 and the length b1b1:
Figures 3 & 4: Length b1 (cm) and Angle θ3(degrees).
The second part of the mechanism depends on the angle and length of link b. The top part of link b extends into the body of the bear and drives the motion of link d. We define the angle of the top part of link b as θ32 and the length that extends into the body as b2.
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