More Like this

1. A Tip Mount for Transporting Sensors and Tools using Soft Growing Robots

   https://doi.org/10.1109/IROS45743.2020.9340950  

   Jeong, Sang-Goo; Coad, Margaret M.; Blumenschein, Laura H.; Luo, Ming; Mehmood, Usman; Kim, Ji Hun; Okamura, Allison M.; Ryu, Jee-Hwan (October 2020, IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS))

   null (Ed.)

   Pneumatically operated soft growing robots that extend via tip eversion are well-suited for navigation in confined spaces. Adding the ability to interact with the environment using sensors and tools attached to the robot tip would greatly enhance the usefulness of these robots for exploration in the field. However, because the material at the tip of the robot body continually changes as the robot grows and retracts, it is challenging to keep sensors and tools attached to the robot tip during actuation and environment interaction. In this paper, we analyze previous designs for mounting to the tip of soft growing robots, and we present a novel device that successfully remains attached to the robot tip while providing a mounting point for sensors and tools. Our tip mount incorporates and builds on our previous work on a device to retract the robot without undesired buckling of its body. Using our tip mount, we demonstrate two new soft growing robot capabilities: (1) pulling on the environment while retracting, and (2) retrieving and delivering objects. Finally, we discuss the limitations of our design and opportunities for improvement in future soft growing robot tip mounts. 

   more » « less
2. Zero-crosstalk silicon photonic refractive index sensor with subwavelength gratings

   https://doi.org/10.1186/s40580-024-00446-1  

   Ahmed, Syed_Z; Hasan, Mehedi; Kim, Kyungtae; Kim, Sangsik (September 2024, Nano Convergence)

   Abstract Silicon photonic index sensors have received significant attention for label-free bio and gas-sensing applications, offering cost-effective and scalable solutions. Here, we introduce an ultra-compact silicon photonic refractive index sensor that leverages zero-crosstalk singularity responses enabled by subwavelength gratings. The subwavelength gratings are precisely engineered to achieve an anisotropic perturbation-led zero-crosstalk, resulting in a single transmission dip singularity in the spectrum that is independent of device length. The sensor is optimized for the transverse magnetic mode operation, where the subwavelength gratings are arranged perpendicular to the propagation direction to support a leaky-like mode and maximize the evanescent field interaction with the analyte space. Experimental results demonstrate a high wavelength sensitivity of − 410 nm/RIU and an intensity sensitivity of 395 dB/RIU, with a compact device footprint of approximately 82.8 μm². Distinct from other resonant and interferometric sensors, our approach provides an FSR-free single-dip spectral response on a small device footprint, overcoming common challenges faced by traditional sensors, such as signal/phase ambiguity, sensitivity fading, limited detection range, and the necessity for large device footprints. This makes our sensor ideal for simplified intensity interrogation. The proposed sensor holds promise for a range of on-chip refractive index sensing applications, from gas to biochemical detection, representing a significant step towards efficient and miniaturized photonic sensing solutions. Graphical Abstract 

   more » « less
3. Soft robots built for extreme environments

   https://doi.org/10.20517/ss.2023.51  

   Kulkarni, Mayura; Edward, Sandra; Golecki, Thomas; Kaehr, Bryan; Golecki, Holly (February 2025, Soft Science)

   Soft material robots are uniquely suited to address engineering challenges in extreme environments in new ways that traditional rigid robot embodiments cannot. Soft robot material flexibility, resistance to brittle fracture, low thermal conductivity, biostability, and self-healing capabilities present new solutions advantageous to specific environmental conditions. In this review, we examine the requirements for building and operating soft robots in various extreme environments, including within the human body, underwater, outer space, search and rescue sites, and confined spaces. We analyze the implementations of soft robotic devices, including actuators and sensors, which meet these requirements. Besides the structure of these devices, we explore ways to expand the use of soft robots in extreme environments with design optimization, control systems, and their future applications in educational and commercial products. We further discuss the current limitations of soft robots recognizing challenges to compliance, strength, and control. With this in mind, we present arguments for the future of robotics in which hybrid (rigid and soft) structures meet complex environmental needs. 

   more » « less
4. Distributed Sensor Networks Deployed Using Soft Growing Robots

   https://doi.org/10.1109/RoboSoft51838.2021.9479345  

   Gruebele, Alexander M.; Zerbe, Andrew C.; Coad, Margaret M.; Okamura, Allison M.; Cutkosky, Mark R. (January 2021, International Conference on Soft Robotics (RoboSoft))

   null (Ed.)

   Due to their ability to move without sliding relative to their environment, soft growing robots are attractive for deploying distributed sensor networks in confined spaces. Sensing of the state of such robots would add to their capabilities as human-safe, adaptable manipulators. However, incorporation of distributed sensors onto soft growing robots is challenging because it requires an interface between stiff and soft materials, and the sensor network needs to undergo significant strain. In this work, we present a method for adding sensors to soft growing robots that uses flexible printed circuit boards with self-contained units of microcontrollers and sensors encased in a laminate armor that protects them from unsafe curvatures. We demonstrate the ability of this system to relay directional temperature and humidity information in hard-to-access spaces. We also demonstrate and characterize a method for sensing the growing robot shape using inertial measurement units deployed along its length, and develop a mathematical model to predict its accuracy. This work advances the capabilities of soft growing robots, as well as the field of soft robot sensing. 

   more » « less
5. A Zero‐Power Optical, ppt‐ to ppm‐Level Toxic Gas and Vapor Sensor with Image, Text, and Analytical Capabilities

   https://doi.org/10.1002/admt.202000058  

   Prévôt, Marianne_Estelle; Nemati, Ahlam; Cull, Tobias_Richard; Hegmann, Elda; Hegmann, Torsten (April 2020, Advanced Materials Technologies)

   Abstract Exposure to hazardous chemicals in the air humans breathe voluntarily or during dangerous situations such as fires or military conflicts (i.e., accidental or intentional) is a terrifying certainty. Technical challenges such as low cost, operational simplicity, response time, sensitivity, specificity, and environmental robustness often create barriers to the development of real‐time chemical sensor systems that will be broadly useful to both the private sector and the government. A multi‐mode liquid crystal sensor platform is presented that requires zero power to operate and can, based simply on the device design, be used as acute ppt‐level and analytical ppm‐level (dose × time) sensors. Inkjet printing of nanoparticles with a reactive ligand shell that affects the anchoring of nematic liquid crystal molecules facilitates the creation of sensors devices that produces an unmistakable warning or image solely based on the transmission or reflection of light. Based on the printing resolution and device architecture, these sensor devices can detect multiple gases or vapors on the same device and be used for remote sensing. 

   more » « less