ENGINEERING RESEARCH JOURNAL (ERJ) Vol. 51, No. 4 October. 2022, pp. 97 1 - 1 8 1 Journal Homepage: erj.bu.edu.eg - 181 - Geometrical and Structural parameters Investigation of an Inclined Air Pillow for Soft Pneumatic Actuator a, b Mahmoud Elsamanty , a Saber Abd Raboo , a Basem Ragab a Department of Mechanical Engineering, Benha University, Egypt b Mechatronics and Robotics Department, School of Innovative Design, Egypt-Japan University for Science and Technology Abstract. Soft actuators have recently been gaining popularity in the field of robotics because of their higher flexibility, lightweight, low cost, and simplicity of fabrication. The traditional rigid grippers have been used widely in industrial applications for a long time. However, when the conventional rigid grippers are used, the grabbing object’s shape must be considered when designing the gripper surface. As a result, the gripper can only hold a limited number of things and occasionally a unique object. In this paper, a novel SPAs geometrical parameter is developed by studying the influence of the change of the chamber wall thickness, base thickness, and the chamber angle on the SPA work envelope when applying a wide range of positive pressure on the inner surfaces of spas. The soft pneumatic actuator (SPA’s) models with large and small thickness ratios are compared by using FEM. The simulation using the finite element method demonstrates that decreasing the wall thickness ratio of the model provides a greater bending angle than the model with a higher wall thickness ratio at the same input pressure. Also, for the change of the chamber angle at an angle equal to zero, the SPAs provide a bending angle only, but when the chamber angle increases, the SPAs provide bending and twisting together. The proposed models still maintain the air surface area inside the actuator. Furthermore, it was observed that when compared to the other models, the lower wall thickness ratio model has the greatest effect on the bending and twisting angles. Finally, an increase in the deformation was observed by 60% and 44.5% of bending and twisting together due to change of the SPA’s wall thickness. Keywords: Soft robotics, Soft pneumatic actuator, hyperplastic material. 1. INTRODUCTION Soft robotics is a new research area that looks to nature to reduce the complexity needed for systems to interact safely with their environments. Unlike conventional robots, which are typically used for repetitive tasks with high precision, also they can be difficult to use outside of controlled environments such as factories due to the difficulties that arise with environmental uncertainty. Another significant possible constraint is the risky relationship between humans and robots. In factories, rigid robots are typically built to move quickly or generate high torques, which can be harmful when close to humans or other fragile objects. Soft robots, in comparison to rigid robots, use soft materials like silicone rubber that can deform while dealing with unfamiliar environments . Moreover, soft robotics seeks to prepare robots for the unpredictable requirements of such circumstances by endowing them with capabilities depending on their bodies’ material properties and anatomy rather than control systems. Consequently, soft robotics and tissue engineering can be combined to build hybrid systems for medical applications [1]. These robots are different from the traditional robots in that they are made of hard materials, and compliance is accomplished with variable stiffness actuators and compliant control to allow .