The three phalanges and base frame m0 with length l0 = 100 mm have been built using commercial bars of an aluminum alloy with a rectangular section 10 30 mm.
In order to obtain a suitable anthropomorphic design the lengths l1 = 90 mm, l2 = 54 mm and l3 = 45 mm have been assumed for the three phalanges, respectively.
A simple procedure is proposed to determine the rotation angles between proximal phalanx and palm, proximal and median phalanges, and median and distal phalanges of the index human finger.
The physical limits such as the length of the finger phalanges, or the ranges of motion for the joints, add complex constraints to the search.
In fact, long phalanges require a greater number of gears for the transmission of motion or a bigger size of gears.
Facial characteristics, broad thumbs and distal phalanges, and partial duplication of the big toes are clearly visible.
Cast shows clear phalanges and joints, and weakly impressed webbing.
The hand consists of three fingers, with two phalanges and two revolute joints each, connected to a rigid palm.