The initial CAD for this project was borrowed from the research paper "An open-source anthropomorphic robot hand system: HRI hand" by Hyeonjun Park and Donghan Kim as a jumping-off point to test how the mechanism behaved before the kinematic analysis was complete. Notably, the authors of this paper chose to actuate each digit individually, while we aim to actuate them all at the same time.
| Link | Length |
|---|---|
| L1 | 6.286 mm |
| L2 | 9.5 mm |
| L3 | 27.05 mm |
| L4 | 27.3 mm |
| Loffset | 3.693 mm |
| L5 | 19.56 mm |
| L6 | 6 mm |
Table 1: Link Lengths
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This prototype had several benefits over the previous one. First, it was better toleranced and assembled more easily since we standardized all the bolt sizes to M3. Secondly, it had a greater range of motion due to the lack of a bolt going across the middle connecting Link 2 to Link 4, which was previously hitting the mechanism and stopping it. Finally, it was overall simpler to manufacture and assemble. Going forward, this is the basic design we will be using for our our final product.
Figure 5: Initial Design 2, simplified linkages
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