Wireless Monitoring of Small Strains in Intelligent Robots via a Joule Heating Effect in Stretchable Graphene–Polymer Nanocomposites

Abstract

Flexible strain sensors are an important component for future intelligent robotics. However, the majority of current strain sensors must be electrically connected to a corresponding monitoring system via conducting wires, which increases system complexity and restricts the working environment for monitoring strains. Here, stretchable graphene–polymer nanocomposites that act as strain sensors using a Joule heating effect are reported. When the resistance of the sensor changes in response to a strain, the resulting change in temperature is wirelessly detected in an intelligent robot. By engineering and optimizing the surface structure of graphene–polymer nanocomposites, the fabricated strain sensors exhibit excellent stability when subjected to periodic temperature signals over 400 cycles while being periodically strained and deliver a high strain sensitivity of 7.03 × 10−4 °C−1 %−1 for strain levels of 0% to 30%. As a wearable electronic device, the approach provides the capability to wirelessly monitor small strains for intelligent robots at a high strain resolution of ≈0.1%. Moreover, when the strain sensing system operates as a multichannel structure, it allows precise strain detection simultaneously, or in sequence, for each finger of an intelligent robot.

Differences and Similarities of Photocatalysis and Electrocatalysis in Two-Dimensional Nanomaterials: Strategies, Traps, Applications and Challenges

“…Today, there is a need to develop new energy under the current worldwide circumstances of increasing environmental pollution and the energy crisis [337][338][339]. Hydrogen energy, as one of new and clean energy resources, possesses not only no secondary pollution, but also has a high energy density and has emerged as a low-carbon and zerocarbon energy.…”

Materials, Electrical Performance, Mechanisms, Applications, and Manufacturing Approaches for Flexible Strain Sensors

“…Flexible and wearable electronics have recently attracted wide attention due to their great potential applications in real-time human health monitoring systems (e.g., detection of human motions [1][2][3][4], heart-beat [5,6], blood pressure [7][8][9], and beyond [10][11][12]), humanmachine interfaces [13][14][15] (e.g., flexible sensors work as a medium and dialogue interface for the transmission and exchange of information between humans and machines), and implantable devices [6,[16][17][18]] (e.g., transmit the sense of skin touch information to the brain by using electronic skin, and prosthesis was controlled by the cerebral cortex with 3D microelectrodes, etc.). The synchronized delivery and control of the signal from human body to detector or actuator are convenient, expeditious, effective, and accurate compared with traditional rigid conducting and semiconducting materials based on smart devices [19,20].…”

Challenges and Opportunities of Self‐Healing Polymers and Devices for Extreme and Hostile Environments

“…Finally, future attractive applications lie in the fields of wireless sensors, [ 137 ] self‐powered sensors, [ 138 ] energy generators, and soft robotics, which are self‐powered and can operate in remote locations such as the ocean, oil fields, and space. Multifunctional and self‐healing polymer based nanocomposites are suitable candidates due to their unique characteristics, such as their lightweight, ease of manufacturing and modification, versatility, and low cost.…”