Automated Sensing Methods in Soft Stretchable Sensors for Soft Robotic Gripper

A soft robot is made from deformable and flexible materials such as silicone, rubber, polymers, etc. Soft robotics is a rapidly evolving field where the human-robot-interaction and bio-inspired design align. The physical characteristics such as highly deformable material and dexterity make soft robots widely applicable. A soft robotic gripper is a robotic hand that acts like a human hand and grasps any object. The most common applications of soft robotics grippers are gripping and locomotion in sensitive applications where high dynamic and sensitivity are essential. Nowadays, soft robotics grippers are used without any sensing method and feedback as it is crucial to make the output feedback from the gripper. The major drawback of soft robotic grippers is their need for more precision sensing. In traditional robots, we can integrate any sensor to detect the force and orientation of objects. Still, soft robotic grippers rely on the deformation sensing method, where the sensor must be highly flexible and deformable. With a precise sensing method, it is easier to determine the exact position or orientation of the object being gripped, and it limits the application of the soft robotic gripper. Sometimes, soft robots are employed in harsh environments to solve problems. With the sensing feedback, automation may become more reliable and succeed altogether. So, in this research, we have designed and fabricated a soft sensor to integrate with the gripper and to observe the feedback of the gripper. We propose integrated multimodal sensing that incorporates applied pressure and resistance change. The sensor provides feedback when the grippers hold any object, and the output response is the resistance change of the sensor. The liquid metal is susceptible and can respond to low force levels. We presented the 3D design, FEM simulation, fabrication, and integration of the gripper and sensor, and by showing both simulation and experimental results, the gripper is validated for real-time application. FEM simulation simulates behavior, optimizing design and predicting performance. We have designed and fabricated a soft sensor that yields microfluidic channel arrays embedded with liquid metal Galinstan alloy and a soft robotic gripper hand. Different printing processes and characterization results are presented for the sensor and actuator. The fabrication process of the gripper and sensor is adequately described. The gripper output characteristics are tested for bending angle, load test, elongation, and object holding under various applied pressure. Additionally, the sensor was tested for stretchability, linearity and durability, and human gesture integration with the finger, and this sensor can be easily reused/ reproduced. Furthermore, the sensor exhibits good sensitivity concerning different pressure and grasping various objects. Finally, we collected data using this sensor-integrated gripper and trained the dataset using machine learning models for automation. With more data, this can be an autonomous gripper with intelligent sensing methodologies. Moreover, this proposed stretchable sensor can be integrated into any existing gripper for innovative real-time applications

Characterization of Vibrio cholerae O1 strains that trace the origin of Haitian-like genetic traits

Vibrio cholerae O1 is the etiological agent of the severe diarrheal disease cholera. The bacterium has recently been causing outbreaks in Haiti with catastrophic effects. Numerous mutations have been reported in V. cholerae O1 strains associated with the Haitian outbreak. These mutations encompass among other the genes encoding virulence factors such as the pilin subunit of the toxin-co-regulated pilus (tcpA), cholera toxin B subunit (ctxB), repeat in toxins (rtxA), and other genes such as the quinolone resistance-determining region (QRDR) of gyrase A (gyrA), rstB of RS element along with the alteration in the number of repeat sequences at the promoter region of ctxAB. Given the numerous genetic changes in those Haitian isolates, we decided to investigate the possible origins of those variations in the Indian subcontinent. Thus, we determined the genetic traits among V. cholerae O1 strains in Delhi, India. A total of 175 strains isolated from cholera patients during 2004 to 2012 were analysed in the present study. Our results showed that all the tested strains carried Haitian type tcpA (tcpACIRS) and variant gyrA indicating their first appearance before 2004 in Delhi. The Haitian variant rtxA and ctxB7 were first detected in Delhi during 2004 and 2006, respectively. Interestingly, not a single strain with the combination of El Tor rtxA and ctxB7 was detected in this study. The Delhi strains carried four heptad repeats (TTTTGAT) in the CT promoter region whereas Haitian strains carried 5 such repeats. Delhi strains did not have any deletion mutations in the rstB like Haitian strains. Overall, our study demonstrates the sequential accumulation of Haitian-like genetic traits among V. cholerae O1 strains in Delhi at different time points prior to the Haitian cholera outbreak

Sustainable bio-energy potential of perennial energy grass from reclaimed coalmine spoil (marginal sites) of India

Usage of marginal lands to grow perennial grass for biomass feedstocks is a promising option to meet the bioenergy demand in India. In this context, the present work investigated the potential utility of two perennial grass species Cenchnis ciliaris (L) and Pennisetum pedicellatum (Tan.) to be a new promising energy source for bioenergy. This study entails a detailed characterization of biomass feedstocks using proximate and ultimate analysis, and lignocellulosic fractions and thermogravimetric behaviour using TG-FTIR and Py-GCIMS spectrophotometry to evaluate their potential as an alternate green fuel to fossil fuels by measuring their thermochemical conversion functioning. Property analysis of perennial grass species showed a significant difference in moisture content (7.2-8.5%), volatile matters (80.5-82.4%), fixed carbon (11.3-18.9%), HHV (15-17.8 Mj/kg) and LHV (14.3-16.5 Mj/kg), which is very promising for bioenergy generation. Lignocellulosic fractions of biomass feedstocks are comparable to the previous studied biomass species including switchgrass and elephant grass. The individual decomposition experiments indicated that biomass feedstocks possess higher thermochemical reactivity and shorter devolatilization time. According to Py-GC/MS study, carbonyl compounds including aldehyde and ketones are the major volatile products, in addition to furans, benzenes, phenols, acids, and others. The TGR1R results showed that main gaseous products evolved during devolatilization are CO, CO2, CH4, and H2O. All of the results and findings would help in characterizing the biomass as potential bioenergy feedstocks compatible with other biomass currently in use as supplementary fuel for power generation. (C) 2018 Elsevier Ltd. All rights reserved

Stretchable Sensors for Soft Robotic Grippers in Edge-Intelligent IoT Applications

The rapid development of electronic material and sensing technology has enabled research to be conducted on liquid metal-based soft sensors. The application of soft sensors is widespread and has many applications in soft robotics, smart prosthetics, and human-machine interfaces, where these sensors can be integrated for precise and sensitive monitoring. Soft sensors can be easily integrated for soft robotic applications, where traditional sensors are incompatible with robotic applications as these types of sensors show large deformation and very flexible. These liquid-metal-based sensors have been widely used for biomedical, agricultural and underwater applications. In this research, we have designed and fabricated a novel soft sensor that yields microfluidic channel arrays embedded with liquid metal Galinstan alloy. First of all, the article presents different fabrication steps such as 3D modeling, printing, and liquid metal injection. Different sensing performances such as stretchability, linearity, and durability results are measured and characterized. The fabricated soft sensor demonstrated excellent stability and reliability and exhibited promising sensitivity with respect to different pressures and conditions

Distribution of soil organic carbon and glomalin related soil protein in reclaimed coal mine-land chronosequence under tropical condition

The revegetation onmine spoiled lands has potential to improve the status of reclaimed mine-soil quality. However, to date the temporal dynamics of labile and stable fractions of soil organic carbon (SOC) and glomalin related soil protein (GRSP) have not been satisfactorily demonstrated. We investigated SOC and GRSP fractions including labile particulate OC (POC) and easily extractable GRSP (EE-GRSP) and stable non-particulate OC (NPOC) and difficulty extractable GRSP (DE-GRSP) along with other important soil properties in six reclaimed mine lands chronosequence (1 to 26 years old) and a reference forest site in Raniganj Coalfield, India. Our results demonstrated that the accumulation of SOC and GRSP significantly increased with increasing age of the sites, with greater extent of increment after 26 years were seen in labile POC (6.6x) and EE-GRSP (11.5x) compared to stable NPOC (1.8x) and DE-GRSP (6.2x). The higher contribution of GRSP-C in NPOC compared to TOC across the sites, indicate the proximate role of GRSP in accumulation and stabilization of SOC during the pedogenesis. The multivariate analysis revealed strong association among arbuscular mycorrhizal fungi (AMF) spore density, microbial biomass carbon, SOCs and GRSPs, suggesting the factors involved in SOC accumulation likely contributed to AMF proliferation and GRSP enrichment during the reclamation process. Moreover, strong correlation of GRSP and SOC with soil's bulk density, pH, total N and C/N ratio, suggest increasing GRSP and SOC content resulted inmulti-level improvement in soil properties. Our results highlight the importance of using GRSP and SOC as indicator during mine land reclamation. (c) 2018 Elsevier B.V. All rights reserved

Pecularities in the distribution of produced particles emission in ²⁴Mg-Ag/Br interactions at 4.5 A GeV*

156-160The angular sub-structures of particle produced within dense and dilute groups along the rapidity axis in 24Mg induced interaction of Ag/Br nuclei in an emulsion detector at 4.5 A GeV/c have been investigated. The experimental results have been compared with the results simulated by Monte Carlo method. Non-statistical jet-like sub-structures have been found in the data. However, when the parameter S2 is used in the analysis there seems to be definite jet-structure for the dilute groups which cannot be accounted for independent emission model (MC). The average behaviour of the S parameters strongly favours the presence of jet-like sub-structures

Laboratory X-ray diffractometer for PDF experiments using Ag radiation

The conventional crystallographic structure solution by X-ray Diffraction technique using Rietveld method prove its great potential for determination of the average structure of the materials for long range periodicity. Experimentally, the structural information of long range periodic atomic ordering of material is reflected in the Bragg’s peaks while local or short rangestructure is reflected in the diffuse peaks. In order to obtain structural information about both average and local atomic structures, need a technique that will consider both Braggs peaks as well as diffuse peaks. Therefore, Total Scattering Atomic Pair Distribution Function (PDF) technique based on Debye Scattering function will be the only possible solution. Atpresent synchrotron and neutron sources are the choice for PDF analysis for short range structure study. But there is a need for routine analysis of such type of samples in a conventional laboratory XRD system to get the quick feedback about the short range structure. PDF analysis can be performed in a Laboratory X-ray diffractometer using Ag radiation (λ =0.5608 Å) to obtain maximum Q value i.e. 22 Å-1. The present work will report PDF based methodology in a laboratory XRD system to extract structural information about nanostructured and disordered materials over short and long range for structural characterization of crystalline and amorphous materials.Present work will report how this PDF technique used to unravel the structure of disordered materials and nanomaterials like amorphous silica, Ni, nano Ba-based Perovskite, etc for better understanding the materials at nano level. Structural information as obtained by the PDF analysis will help to control the performance of the disordered materials for tailoring thematerials at nano scale. This method may be applicable to the characterization of the nanoscale crystalline and amorphous materials based on PDF analysis in Laboratory XRD system using Ag Radiation. This proposed experimental technique will help to quick feedback about local or disordered structure based on PDF using Ag radiation in a laboratory XRD system