Fig. 2: Benchtop mechanical testing results.
a Experimental setup, in which the prototype thumb is clamped into an adjustable load frame and loaded with the proxy MCP joint locked at different angles. b MCP-IP angle relationships showing the target trajectory, the idealized linkage design, the clinically viable linkage design, and the experimental performance of the physical prototype (Supplementary Table 1). c Deflection of the thumb-tip marker across seven locked proxy MCP angles. d Stiffness of the device as a function of MCP angle. Stiffness represents the amount of perpendicular force required at the thumb tip to produce 1 mm of linear deflection of the thumb tip. e Experimental MCP-IP angle relationship in the presence of different loads. Dots show average measured angle over 1.5 s, and solid lines show first-order linear regression fits. The dashed line represents model predictions for the clinically viable device (identical to the solid blue line from (b)).
