Enhancements of Loading Capacity and Moving Ability by Microstructures for Wireless Soft Robot Boats

Abstract

Because of its promising applications in various fields such as in vivo drug treatment, in-pipe inspection, and so forth, there is an increasing interest on wireless soft robot boats taking advantages of their shape adaptability. The loading capacity and mobility, however, are always fundamental challenges to restrict their applications. In this study, a graphene-based soft robot boat, which could be programmable-driven by a remote nearinfrared light, is proposed. Different microstructures underneath the boat are carefully designed and employed to improve both the loading capacity and the moving ability. It reveals that, compared to that without microstructures, the soft robot boat with square pillar arrays (120−160 μm of period, duty cycle, and aspect ratio at active Wenzel/Cassie transition point) could enhance the loading capacity by 12.75% and the moving velocity by 16.70%. For the robot boat with grating structures, a strong driving anisotropy is revealed, with an enhancement of 2.24% for the loading capacity and 34.65% for the driving response along the grating lines. A boat prototype with a self-weight of 6.05 g is finally developed and can achieve continuous navigation in a closed narrow space for in situ monitoring, which may find applications in the inspection of other narrow terrains (e.g., blood vessels).

Porous Microstructure‐Assisted Flexible and Highly Sensitive Polymer Piezoresistive Pressure Sensor

“…The addition of porosity into the substrate increases the surface roughness on an already-microstructured surface of conductive layer of PEDOT:PSS. Now, this leads to a further high rate of change of resistance with applied pressure, as per Figure 3 and Equation (10), where now there is more room to deform. Also, the ease of compressing the microstructures increases with the decreased effective elastic modulus with increased porosity, increasing the rate of deformation of the microstructures and hence the increased rate of change of resistance with applied pressure (or increased sensitivity).…”

“…[ 6 ] Flexible pressure sensors are broadly used in artificially intelligent systems [ 7 ] and healthcare monitoring systems. [ 8 ] A great potential exists for their use in electronic skin (e‐skin), [ 9 ] soft robots, [ 10 ] and sensing of biosignals. [ 11 ] In addition to being flexible, such sensors are lightweight and have low cost, which make them quite viable commercially.…”

Spiral‐Shape Fast‐Moving Soft Robots

“…Figure A shows a comparison of relative speeds versus body weights including our robots (red stars) and reported artificial soft robots using piezoelectric materials (blue balls), magnetic materials (blue squares), heat materials (blue hollow squares), and dielectric elastomers (blue hollow triangles). [ 66,73–95 ] The relevant data are represented in Table S3 (Supporting Information). The five red triangles represent the weight and relative motion speed of the five soft robots with different body lengths from 5 mm to 30 mm, and the fastest relative speed can reach 76 BL s −1 (absolute speed of 38 cm s −1 under square driving voltage of 200 V at 247 Hz), which is more than triple as fast as the current insect‐scale piezoelectric soft robot (20 BL s −1 ).…”

Design and mechanism of photothermal soft actuators and their applications

“…10b and c, the graphene-based navigated boat is driven by light for in situ navigating in narrow terrains. 204 The wireless, contactless, and light-driven robot boat has promising transportation and in-pipe inspection applications. The microstructure created by square pillar arrays underneath the boat could enhance the loading capacity by 12.75% and moving speed by 16.7% compared to that without a microstructure.…”