Adaptive Gripper MkII
 Rendered CAD assembly |  Internal components: motor, gear transmission, and 5-bar linkage system |  Adaptive Gripper MkII at 2022 competition |
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 Back view with positioning laser (2022) |  Up close on machined fingers (2022) |  Retrofitted Adaptive Gripper Mk II for 2023 competition |
 Retrofitted carbon fiber-reinforced nylon fingers after being dragged through the dirt (2023) |
Gripper with 5-bar linkage system and adaptive parallel grip
Sep - Dec 2020,
July - Aug 2023
The Adaptive Gripper MkII is designed to grip objects with variable widths, using a 5 bar-linkage system to precisely control the parallel fingertips. We refined the 5-bar linkage system from the MkI version with new calculations, finding the most optimal spring constant and position to properly limit the degrees of freedom, and created all new TPU (flexible) 3D printed fingertips for maximum compliance around objects. I personally designed the new camera mount, placed further back on the hand to increase the field of vision and collaborated with the Electronics Subsystem to optimally place the wiring and new motor board.
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In preparation for the 2023 Canadian International Rover Challenge, we retrofitted this gripper (since the newly designed one wasn't ready yet). I printed the new finger linkages and gears on a Markforced FDM desktop printer with their Onyx filament—chopped carbon fiber-infused nylon—which were extremely strong and resistant to the abuse of competition. I also adjusted the internal features of the gripper's body to prevent overly tight fits, particularly around the limit switch and gears, and we printed it out of PETG rather than PLA, which cracked underneath the captive nuts at the 2022 competition. Overall, the retrofitted hand held up much better and didn't break once in 2023.
​Results:
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Eliminated previous history of finger breakage by machining instead of 3D printing them, and consulted with the Manufacturing subsystem to ensure they were machinable
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Prevented damage to wires by completely enclosing wires within housing
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Upgraded to interchangeable wrist mount, allowing the hand to be quick changed during competition
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Improved operation/handling by adding positioning lasers and moving camera location to increase field of vision