Question

What is the relative angle (in degrees) of the knee if the hip joint center is (1.14, 0.79), the knee joint center is (1.17, 0.51), and ankle joint center is (1.10, 0.08). .

Answer 1

The cordinates of hip joint center = (1.14,0.79)

knee joint center = (1.17,0.51)

ankle joint center = (1.10,0.08)

and are unit vectors along the x and y - axis.

The vector joining knee joint center and hip joint center() = (1.14-1.17)+(0.79-0.51)

= 0.03 + 0.28

The vector joining knee joint center and ankle joint center() = (1.10-1.17) + (0.08 - 0.51)

= -0.07 -0.43

Angle between and =