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An ideal mechanism path would achieve perfect linear motion of the output point as the linkage system reaches 90 degrees and 0 degrees relative to the ground, allowing for the isolation of the grabber mechanism movement relative to the rotational component of the overall system. This ideal linkage system input path is demonstrated in the curved slot and full linkage system below.
The force profile/mechanical advantage of the end effector should ideally peak at the maximum close position (small relative distance between critical points) to maintain adequate contact with the object being picked up. The plot below demonstrates a possible ideal plot of mechanical advantage, calculated from the design of end effector iteration two. For future iterations, a better alternative would be to design a system that achieves a mechanical advantage that approaches infinity as the linear displacement decreases.
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