Conformable and Compact Multiaxis Tactile Sensor for Human and Robotic Grasping via Anisotropic Waveguides

Abstract

Rich and accurate tactile perceptive capability is important for both humans and robots. Soft materials exhibit unique characteristics to construct high‐performance tactile sensors such as high sensitivity and high resistance to overload. In this work, a multiaxis tactile sensor based on a soft anisotropic waveguide that can distinguish normal force and shear force, which can greatly expand its potential uses in practice, is reported. First, the anisotropy of the waveguide sensor's response to vector forces is validated numerically and experimentally, and then two of those anisotropic units are embedded into one cladding with a crossed‐over layout, to form a multiaxis sensor. Then, a calibration algorithm is implemented on this sensor and the reconstruction of vector forces is achieved at an average accuracy of 28.0 mN for normal forces and 81.1 mN for shear forces, both with the sensing range of 1 N. Using this device, three demonstrations are shown to give outlooks of its potential application in human and robotic grasping tasks: a wearable tactile sensor for collecting human's haptic data during operation, a uniaxial gyroscope, and a robotic gripper's tactile sensor for assisting an unlocking task with a key. This work is a step toward more functional soft waveguide‐based force sensors.

Packaged Elastomeric Optical Fiber Sensors for Healthcare Monitoring and Human‐Machine Interaction

“…Recently, EPOF-enabled sensors have been widely used for body movement monitoring [33,34] or robotic skin. [35] These reports shed light on the development of flexible optical sensors. However, a soft EPOF without effective protection tends to be damaged, which may undermine its longterm stability, and thus, limit its practical applications.…”

Modeling the resistive viscoelasticity of conductive polymer composites for sensor usage

“…Substituting eqn ( 14) and ( 15) to eqn (6), we obtain the strain and rate dependence of the resistance as: R R 0 ðtÞ ¼ R 0 1 þR 10 eðtÞexpðk 10 eðtÞÞ 1þa ln 1þb…”

“…Along with the rapid development of wearable electronics, electronic skin, and soft robots, interest in manufacturing soft resistive sensors has been growing significantly. [1][2][3][4][5][6][7] Conductive polymer composites (CPCs) are commonly used to fabricate soft resistive sensors due to their excellent mechanical properties, outstanding electrical performance, and low fabrication cost. 8 CPCs are usually prepared by adding conductive nanomaterials such as carbon-type nanoparticles (NPs), metallic NPs, or metal nanowires into the polymer matrix.…”

Skin‐Adhesive Flexible Force Sensors Based on Piezoelectric Poly(l‐lactic acid) for Human Behavior Recognition

“…A flexible force sensor for human motion recognition is of great importance for human-machine interaction, entertainment, and rehabilitation. [1][2][3][4][5][6] In recent years, piezoelectric polymers with reasonable piezoelectric coefficient, low dielectric constant, good processibility, excellent flexibility, and low cost, have been intensively investigated in flexible sensors and nanogenerators. [7][8][9][10][11] Due to these outstanding properties that can be controlled, it has gradually become one of the research hotspots in the field of body-integrated devices or E-skin.…”