Crossbow Team #2 (The REAL team)

Scope of project:

  • Modify parent design from thingiverse: https://www.thingiverse.com/thing:200976
  • Re-design thingiverse model to eliminate post processing on the ratchet mechanism
  • Optimize body strength/weight ratio using FEA
  • Replace the existing two-part bow with a one-part bow system

 

Ratchet Mechanism Redesign

The goal of the ratchet re-design is to remove post process machining by eliminating the set screw mounting the handle to the pin of the ratchet system.

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Fig 1

 

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Fig. 2

 

Optimize Body Strength/Weight Ratio

The thingiverse crossbow body was much larger than it needed to be. We aim to redesign the body by removing material in locations of no stress. Fig. 3 highlights the region of the body that is to be redesigned.

 

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Fig. 3

This is accomplished by cutting out the center body and utilizing modular meshes that were indicated by FEA. These meshes will slide into the highlighted area in Fig. 3 to support loading stresses.

 

Bow System Redesign

The thingiverse design utilized a split bow system that seemed overly complex. This isn’t the focus of the optimization of the crossbow and we decided to simplify it to a single part bow system.

 

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Fig. 4