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The top portion of the mechanism can be modeled as a closed loop composed of one ground link (green), a grounded sliding joint, and two links. The angles and angular velocities of the joints can be derived as a function of the input angle, from the cyan link, which is solved for in the analysis of the bottom linkage.
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The position analysis solves for the slider's linear position and the angular position of the distal finger.
Because of their complexity, these equations were solved using a symbolic solver to yield the following solutions:
The velocity analysis was then performed by differentiating the same vector loop, this time solving for the slider linear velocity and distal finger angular velocity.
Shown below are plots of the angular positions and velocities of the two gripper finger links (color-coded to match the CAD figures) for the full range of input slider displacements where 0mm of input displacement corresponds to the gripper in its maximally closed grasp state and roughly 80mm of slider displacement corresponds to the gripper in its most open, widest stance landing-gear state.
A video showing the mechanism moving through its full range of motion is shown below. A qualitative comparison between the above plots and the mechanism's motion in the video confirms the accuracy of the derived equations.
Multimedia name RMD_mechanism_movement2 (1).mp4 width 100%