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Overview
The goal of this mechanism is to create a crank-mechanism that primarily rocks in xy-plane, but has the ability to jump in the z direction.
Mobility Calculations:
M = 3(L-1) - 2J1 - J2 (Gruebler's Equation)
M = 3(4-1) - (2*4) - 0
M = 9 - 8
M = 1
3D Output Path
This is the target output path for the crank rocker in the z direction. This will be achieved using a cam.
Kinematic Analysis and Plots
Angular Output
Position on the XY Plane
The end of link 4 (the desired output link) makes a full arc in a negative parabolic shape. The cat wand toy will be attached to the end of link 4, making it also follow a parabolic motion.
Linear Velocity
As you can see in this figure, Link 4 and Link 3 both have a wave-like velocity profiles. Link 3 hits its max velocity 4 times per rotation and is less uniform while Link 4 moves faster and hits its max velocity 2 times per rotation.
Angular Acceleration
Force Profile
Mechanical Advantage