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Figure 5.25
Bending angle against force and photographs of the experiment.
5.4.2.2.2 Stability
Effect of disturbance force on lateral displacement The aim of this experiment was to
determine the stability of the prototype when subjected to lateral disturbance forces in two
phases, namely before and after actuation.
Disturbance force was stimulated by means of a hand flick. The prototype was flicked from
both the left and right direction. When flicked from the right, a positive lateral displacement
was expected, whereas when the device was flicked from the left, a negative lateral
displacement was expected. To measure the stability before and after actuation, the lateral
displacement of the tip marker was measured. A decrease in lateral displacement was
expected after actuation to prove that the prototype was stable.
As shown in Fig. 5.26, from 0.5 to 6.6 seconds, disturbance force was applied to the tendon
by means of a hand flick. The tendon was then pulled at 6.6 seconds, and the prototype was
compressed and became rigid. A significant decrease in the axial displacement was
observed from 6.6 seconds. An average displacement of 3.04 cm was observed as a
prototype became rigid.
Discussion: The following experiment proved that the prototype became rigid as it was
actuated. The average displacement, which was 3.04 cm, was higher than the permissible
displacement.
Effect of disturbance force on longitudinal displacement The objective of this experiment
was to measure the longitudinal displacement of the prototype’s tip when subjected to
