*3.4. Representation of Variations in Tendon Lengths*

Once tendon distances are adjusted to the joint kinematics, with the blocking angle restrictions, distance changes for each tendon can be represented as inclination and orientation input angles vary. Figure 15 shows tendon lengths according to inclination and

orientation variations, the restrictions imposed by the design morphology, 0 to 359° orientation degrees and 0 to 170° inclination degrees, and the final length in meters.

**Figure 15.** Representation of each tendon length variation for all possible values of inclination and orientation of the soft joint. The initial length of each tendon is 0.2 m (rest position). A color range from yellow to dark blue is used to show the variation from the highest tendon length value (yellow) to the lowest value (dark blue). (**a**) Length *L*<sup>1</sup> corresponding to tendon 1, (**b**) Length *L*<sup>2</sup> corresponding to tendon 2, (**c**) Length *L*<sup>3</sup> corresponding to tendon 3.

These graphs show how each tendon *Li* varies according to inclination and orientation. The higher the inclination, the higher the variation of tendon length with changes of orientation. For a fixed inclination, when the orientation changes, as in a rotational movement, the tendon length increases and decreases in a sinusoidal shape, with the orientation corresponding to a maximum, a minimum or the initial length value. Due to the soft joint blockages, from certain degrees of inclination, the variation of tendon lengths is not sinusoidal, and, for certain orientation angle ranges, the length remains fixed.
