Before we began our design, we reviewed a few research papers that helped us understand finger kinematics. One paper we reviewed created a simplified model of the finger using a triangular shape to find the general maximum angles and angle ratios that can be used to simulate finger movement (Kim, 2008). This can be seen in figure 3. The corresponding formulas used are seen after. Figure 3: Angles in the finger
Another research paper we reviewed gave general length ratios of each phalanx taking the distal as 1.0, medial as 1.5, and proximal as 2.4 (Buryanov, 2010). This allowed us to better understand the length ratios and angle ratios that need to be met in the design to achieve a relatively natural finger movement of the prosthetic.
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