The Effect of Geometric Parameters on Bending in Soft Actuators: FEM Simulation

Abstract

Soft pneumatic actuators have attracted considerable attention in recent years due to their flexibility and adaptive motion capabilities. However, existing studies examining the influence of geometric design parameters on mechanical behavior remain limited. In this study, the effects of key design parameters—such as the presence or absence of an internal radius and overall actuator length (105 mm and 139 mm)—on the bending behavior of a hollow-chamber soft pneumatic actuator under different pressure conditions were numerically investigated. The actuator geometry was modeled using Fusion 360, and the hyperelastic properties of the silicone material were defined by the Mooney–Rivlin model. Mechanical analyses were conducted in ANSYS using the Finite Element Method (FEM) for internal pressure levels of 5, 10, and 15 kPa. The results indicate that variations in geometric parameters can significantly affect both the magnitude and pattern of actuator bending. These findings highlight the importance of considering geometric factors in the design and performance optimization of soft pneumatic actuators.

Keywords

• 3D design
• Soft flexible actuator
• Bending angle
• Finite element analysis

Yumuşak Aktüatörlerde Geometrik Parametrelerin Bükülmeye Etkisi: FEA Simülasyonu

Abstract

Yumuşak pnömatik aktüatörler, esnek yapıları ve adaptif hareket kabiliyetleri sayesinde son yıllarda geniş bir ilgi alanı oluşturmuştur. Bununla birlikte, geometrik tasarım değişkenlerinin mekanik davranış üzerindeki etkilerine ilişkin mevcut çalışmaların kapsamı sınırlıdır. Bu çalışmada, içi boş odacıklı bir yumuşak pnömatik aktüatörün radius varlığı/yokluğu ve boyut (105 mm ve 139 mm) gibi tasarım parametrelerinin, farklı basınç koşulları altında bükülme davranışı üzerindeki etkileri sayısal olarak incelenmiştir. Aktüatör geometrisi Fusion 360 yazılımında oluşturulmuş, silikon malzemenin hiperelastik özellikleri Mooney–Rivlin modeliyle tanımlanmıştır. Mekanik analizler ANSYS ortamında Sonlu Elemanlar Yöntemi (FEA) kullanılarak gerçekleştirilmiş ve 5, 10 ve 15 kPa iç basınç seviyeleri için tekrarlanmıştır. Analiz sonuçları, geometrik parametrelerdeki farklılıkların aktüatörün bükülme miktarı ve şekli üzerinde belirgin bir etkiye sahip olabileceğini göstermektedir. Bu bulgular, yumuşak pnömatik aktüatörlerin tasarımında geometrik değişkenlerin dikkate alınmasının performans açısından önemli olduğunu ortaya koymaktadır.

Keywords

• 3 Boyutlu tasarım
• Yumuşak esnek aktüatör
• Bükülme açısı
• Sonlu eleman analizi

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