Final Gripper Prototype Construction

Final Prototype

Changes from first prototype:

• Machined 7075 aluminum to a high precision while allowing high strength to low weight

• Changed our two bar linkage to a four bar linkage to enhance the release mechanism

• Created a better wedge mechanism to allow for more successful release

• Attached mechanism to a leather glove for comfort and less freedom of movement of the device on the hand

Mechanical Features

• Used existing rope cam cleats normally found on sail boats since they are designed for this use

• Key-ways were machined into the cam cleats to mate with matching ridges machined into the larger links in order to prevent the cams from rotating on the links

• The slider is machined out of Delrin in order to decrease the friction between the slider and the base plate

• The whole mechanism is attached to a weight lifting glove via rivets, which allows for a minimal but sturdy connection

• Springs in baseplate and slider, as seen in the top right of Figure 11, return the mechanism to a closed configuration after the user opens the mechanism

User Interface Features

• The weight lifting glove stays put on the user’s hand with the use of finger holes and wrist strap, but it also has minimal footprint that allows the user full movement of their thumb 
• A slider/cam activation method was chosen because it allows the user to either push or pull the slider to open the cams
• The push/pull method allows for the mechanism to be placed on either hand and side of the hand without needing any change to the design to have the mechanism properly work

• The placement of the links was designed so that the height of the total mechanism is at a minimum to reduce the rotating moment caused by the tension in the rope pulling against the cams so it doesn't pull down the user's hand

Figure 11: Outer Dimension of device without cam cleats attached (Top Left and Bottom) Hidden View of Assembly to show springs in base plate and slider (Top Right)