IJSTR >> Volume 9 - Issue 12, December 2020 Edition

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AUTHOR(S)

Mariam Md Ghazaly, Muhammad Izzat Mohd Jahid

KEYWORDS

Bending angle, design optimization, FEM analysis, pneumatic actuator, soft actuator, soft robotics, soft pneumatic.

ABSTRACT

In these previous years, it has been reported that machinery has caused injuries and deaths in the industries. Machineries consist of moving mechanical parts that are mostly actuated by hard conventional actuators. Using conventional actuators could result in injuries, leading to complications during human robot interaction. Due to their hard physical features, it is difficult to implement conventional actuators in various environments except in industry. Due to such difficulties, these issues are mitigated by introducing soft actuators. Soft actuators are built out of soft materials similar to silicon and are actuated when air pressure is introduced as well as on inflating the internal fluidic channel. This results in the soft actuator to create a bending motion. Such types of actuators include a broad range of application; however, the issue here would be to control the bending motion pertaining to the soft actuator, and thus this warrants an analysis for such types of actuators. This research aims to design and characterize two classes of soft bending actuator by employing FEM analysis in order to optimize the bending motion pertaining to two classes of soft bending actuator. Two types of soft actuator designs were analyze, i.e. the (i) PneuNets soft bending actuator and (ii) Fibre-reinforced bending actuator. For both designs, optimization was done via Finite Element Method (FEM) analysis using Abaqus software by varying three parameters, i.e.: (i) height of chamber, (ii) length of chamber and (iii) width of chamber/ fiber angle. The FEM analysis shows that the fibre-reinforced soft actuator exhibit higher bending motion, 217.5mm in compared to PneuNets soft bending actuator, 160.9mm respectively. The bending motion can also be controlled direction by varying the fibre angle in the fibre-reinforced actuator. This gives the fibre-reinforced actuator a broader range of motion in compared to PneuNets actuator.

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