Characterization of 3D printed multi-material soft pneumatic actuator

Soft Pneumatic Actuators (SPA) are among the most reliable soft actuators, as they are moved by pressurized air and are relatively easy to create and use. The fabrication of SPA can be achieved using various techniques, among which fused deposition modeling (FDM) has emerged as a promising option. This study investigated the fabrication of a multi-material SPA using the FDM technique with commercially available materials, namely eFlex and Elastic. The displacement, angle, diameter, and length data of all SPAs were analyzed and compared between eFlex, Elastic, and the combination of both materials. To quantify and validate the effect of materials and pressure on the output, MANOVA, and ANOVA assessments were applied. The statistical test results show that the material has a significant effect on length and angle but does not have an effect on the SPA diameter. Meanwhile the pressure has significant effects on the diameter and angle, but not the length. The pressure experiment shows that single-material SPAs, particularly eFlex with an average maximum pressure of 5.375 bar, outperform multi-material SPAs in pressure endurance. While Elastic also performs well at 4.25 bar, multi-material SPAs like Elastic-eFlex and eFlex-Elastic have lower endurance, averaging 4 bar and 3.25 bar, respectively.