3D Printing Materials for Soft Robotics

Abstract

that uses the sensor-generated information to accurately regulate and enhance the dynamic performance.Soft robots (and more in general soft material-based systems) can be built with a plethora of materials and composites having very different mechanical properties, spanning from fluids (i.e., liquid metals, etc.) and hydrogels, to stiff solids (i.e., acrylonitrile butadiene styrene (ABS), epoxy resins, etc.). Also, in most cases, the constituent materials have many degrees of freedom and are highly non-linear, with relevant hysteresis and viscoelastic behavior. Hence, modeling soft systems is a very challenging task, and it still misses a comprehensive theoretical foundation. [19] As a result, the modeling phase is often overlooked in the design process, which in most cases relies on trial and error experimentation. The most commonly used materials in the design of soft robotics are silicone-based elastomers, such as polydimethylsiloxane (PDMS). They are used as the flexible material in pneumatic actuators, [4,5,14] in magnetic actuators, [11] and in electrically driven actuators as well, usually along with a conductive layer, commonly a carbon-based material. [15,16] Besides, other flexible polymers such as polyimides, [8] polyurethanes (PU), [12,20] or hydrogels [9] are used. So far, most devices are fabricated by casting or molding of liquid monomers, followed by hardening by UV light or heat.3D printing is an additive manufacturing technique, in which a required material is deposited, layer by layer, to form a 3D object, that is, it is a sequential 2D printing. The main advantages of 3D printing over subtractive manufacturing methods, are the simplicity of the process and the ability to form complex and hollow structures. There is a variety of 3D printing technologies that are commercially available, as described in a diversity of review reports. [21][22][23] Therefore, we will present here only a concise description of the printing technologies that are most relevant to soft robotics, all of them are based on ink compositions which are liquid during the printing processes.The most widely used methods are based on extrusion of materials, called fused deposition modeling (FDM) [24,25] and direct ink writing (DIW). [26,27] Both methods rely on a material that is extruded through a nozzle onto a substrate, and differ by the materials being used, the nozzle's nature, and the fixation mechanism. In FDM, a thermoplastic filament is extruded through a heated nozzle, followed by solidification upon cooling on the substrate, to form a solid 2D layer. This technique is simple and not expensive, but is limited to thermoplastic polymers and has relatively low resolution. In DIW, a viscous Soft robotics is a growing field of research, focusing on constructing motorless robots from highly compliant materials, some are similar to those found in living organisms. Soft robotics has a high potential for applications in various fields such as soft grippers, actuators, and biomedical devices. 3D printing of soft robotics present...

Smart and Biomimetic 3D and 4D Printed Composite Hydrogels: Opportunities for Different Biomedical Applications

“…Electroconductive 4D printed materials can be used in the field of electronics [ 316 , 317 ]. Parameters that play a significant role include voltage, electrical conductivity, and mechanical properties.…”

“…So that, after halving the actuator, it recovered the initial structure and actuation ability by a disulfide metathesis reaction. Subsequently, the polymeric network self-healed at 60 °C for 2 h, and the self-healing process was sped up by rising temperatures [ 316 ].…”

Industry 4.0 and Comparison of 3d Printers

“…Bu anlamda FDM 3B yazıcılar otomotiv [52] ve medikal [53] gibi yüksek katma değerli endüstrilerden oyuncak üretimi [54] veya gündelik kişisel ürünlere [55] kadar çok geniş bir yelpazede kendine uygulama alanı bulmaktadır. Fotopolimerizasyon Çalışmaları: Fotopolimerizasyon tekniğini kullanan 3B yazıcılar çok çeşitli alanlarda uygulamaları bulunmaktadır: akıllı kompozitler [64], yumuşak robotik [65], protezler ve ortezler [66].…”

A Dual-origami Design Enables the Quasi-sequential Deployment and Bending Motion of Soft Robots and Grippers

“…Meanwhile, 3D printing has been recently studied as an automotive fabrication method for soft robots. (Polygerinos et al, 2017;Yap et al, 2016;Low et al, 2020;Sachyani Keneth et al, 2021;Wallin et al, 2018) In particular, FDM is a prominent and popular open-source technology with economic merits of low initial and maintenance costs. The final products can be built without supports by bridging gaps within a few centimeters, and in recent studies, researchers have directly fabricated conventional soft bending actuators made with commercially available TPU filaments.…”