Three-dimensional printing of tactile sensors for soft robotics

Xinran Zhou,Pooi See Lee

doi:10.1557/s43577-021-00079-3

Abstract

Three-dimensional (3D) printing has become an important fabrication method for soft robotics, due to its ability to make complex 3D structures from computer designs in simple steps and multimaterial co-deposition ability. In this article, the application of 3D printing techniques in the fabrication of four types of tactile sensors commonly used in soft robotics, including the piezoresistive tactile sensor, capacitive tactile sensor, piezoelectric tactile sensor, and triboelectric tactile sensor, will be discussed. The 3D printing mechanism, material, and structure for each type of sensor will be introduced, and the perspectives on the future potential of 3D printable tactile sensors will be discussed.

Highlights

Different from traditional robots made of rigid materials, soft robots rely on highly compliant materials to be flexible and adaptable to move and work in complex environments and accomplish unique tasks
Sensors are one of the essential components in soft robotics, which include tactile sensors, motion sensors, biological sensors, and chemical sensors
Tactile sensors are one of the most important sensors for soft robotics since they can perceive the physical interaction with the environment, and the feedback information can be used to guide the robot to achieve more accurate motions such as grasping or movement

Summary

Introduction

Different from traditional robots made of rigid materials, soft robots rely on highly compliant materials to be flexible and adaptable to move and work in complex environments and accomplish unique tasks. Guo et al developed a series of room-temperature curable inks and used the DIW technique to print the whole piezoresistive tactile sensor, including the silicone Comparing this to traditional fabrication methods, the largest advantage for 3D printing is the capability of making complex macrostructures, which could affect the sensing performance by influencing the strain on the sensor during deformation. The a stretchable piezoelectric sensor with a photocurable barium titanate (BTO) nanoparticle/PUA composite by DLP.[10] since the 3D printable piezoelectric materials are not single crysknots at the crossing of the axial and transverse printing tals, they require an additional poling step to align the internal paths form microdomes that deform and generate different dipoles This poling step can be combined with the FDM or DIW internal ions’ distribution under pressure, which exhibits a high sensitivity of 72.86 kPa−1 in the ultralow pressure range process by applying voltage between the extrusion needle and the platform (Figure 4c). The co-axial filament-based triboelectric sensor can achieve realtime monitoring of organism swelling and speech recognition in the absence of sound

Conclusion

Findings

Conflict of interest