Behavior modeling of pneumatic soft bending actuators in free and contact conditions

Pneumatic Soft bending actuators as safe and highly adaptable robots are being considered by researchers, such that they become an ideal choice for making devices that interact more with humans. These advantages come along with several disadvantages. Their great adaptability is provided by their high degrees of freedom, and consequently, it makes the modeling a significant challenge for researchers. In this paper, the modeling of a soft fiber-reinforced bending actuator that is in contact with the environment has been conducted by utilizing the finite rigid element method. This method provides a context within which the modeling theories of traditional rigid robots, such as the Denavit-Hartenberg method, become usable for a soft continuum actuator. Therefore, in the following, resorting to this theory, the static and dynamic behavior of a soft actuator under the effect of the external load has been investigated and compared with the empirical results derived from a fabricated actuator. The results show a minimum accuracy of 9 percent, although being as simple as can be used for other purposes like implementing control systems based on that.