Deep reinforcement learning for soft, flexible robots : brief review with impending challenges

The increasing trend of studying the innate softness of robotic structures and amalgamating it with the benefits of the extensive developments in the field of embodied intelligence has led to the sprouting of a relatively new yet rewarding sphere of technology in intelligent soft robotics. The fusion of deep reinforcement algorithms with soft bio-inspired structures positively directs to a fruitful prospect of designing completely self-sufficient agents that are capable of learning from observations collected from their environment. For soft robotic structures possessing countless degrees of freedom, it is at times not convenient to formulate mathematical models necessary for training a deep reinforcement learning (DRL) agent. Deploying current imitation learning algorithms on soft robotic systems has provided competent results. This review article posits an overview of various such algorithms along with instances of being applied to real-world scenarios, yielding frontier results. Brief descriptions highlight the various pristine branches of DRL research in soft robotics

Wearable and Stretchable Strain Sensors: Materials, Sensing Mechanisms, and Applications

Recent advances in the design and implementation of wearable resistive, capacitive, and optical strain sensors are summarized herein. Wearable and stretchable strain sensors have received extensive research interest due to their applications in personalized healthcare, human motion detection, human–machine interfaces, soft robotics, and beyond. The disconnection of overlapped nanomaterials, reversible opening/closing of microcracks in sensing films, and alteration of the tunneling resistance have been successfully adopted to develop high-performance resistive-type sensors. On the other hand, the sensing behavior of capacitive-type and optical strain sensors is largely governed by their geometrical changes under stretching/releasing cycles. The sensor design parameters, including stretchability, sensitivity, linearity, hysteresis, and dynamic durability, are comprehensively discussed. Finally, the promising applications of wearable strain sensors are highlighted in detail. Although considerable progress has been made so far, wearable strain sensors are still in their prototype stage, and several challenges in the manufacturing of integrated and multifunctional strain sensors should be yet tackled

Frequency Driven Alteration In Cellular Morphology During Ultrasound Pulsing In A Microfluidic Confinement

To instigate therapeutic potential of low-intensity ultrasound further, it is essential to characterize the bio-physical interaction of living cells with alteration of ultrasound frequency. Although, this study is frequently been the subject of speculation in therapeutic ultrasound regime there has been a distinct shortage of attempts to characterize in situ physical-biological interaction in this process. The dearth of effort in this domain inherently calls for our investigation on frequency dependent shape transition in micro onfined biological cells. Here, we used a microfluidic platform for single cell analysis with bio-physical interaction to ultrasound frequency alteration, in line with the fact that microfluidic channels to a large extent mimic the confinement effect induced by micro confinement of physiological pathways. In this dissertation, with the help of series of single-cell direct observation, we show that low intensity ultrasound frequency alteration would reversibly perturb cell membrane structure and count for inherent cell oscillation. However, during post exposure ultrasound period the cytomechnical perturbation of cell membrane is relatively more compared to ultrasound exposure period leading to an inherent residual strain which follows a transition zone near to the resonating frequency of the composite system. Together, these findings indicate that alteration of low intensity ultrasound frequency, if applied to a microfluidic platform on the order of minutes, would produce a reversible effect on physical structures of living cells based on the system resonant frequency during and post exposure ultrasound pulsing.by Hritwick BanerjeeM.Tech

Modelling, optimization and control of droplet based microfluidic technology for single-cell high-throughput screening

by Hritwick Banerjee and Babji Srinivasa

Hydrogel Actuators and Sensors for Biomedical Soft Robots: Brief Overview with Impending Challenges

There are numerous developments taking place in the field of biorobotics, and one such recent breakthrough is the implementation of soft robots—a pathway to mimic nature’s organic parts for research purposes and in minimally invasive surgeries as a result of their shape-morphing and adaptable features. Hydrogels (biocompatible, biodegradable materials that are used in designing soft robots and sensor integration), have come into demand because of their beneficial properties, such as high water content, flexibility, and multi-faceted advantages particularly in targeted drug delivery, surgery and biorobotics. We illustrate in this review article the different types of biomedical sensors and actuators for which a hydrogel acts as an active primary material, and we elucidate their limitations and the future scope of this material in the nexus of similar biomedical avenues

The Demographic Diversity of Food Intake and Prevalence of Kidney Stone Diseases in the Indian Continent

Food intake plays a pivotal role in human growth, constituting 45% of the global economy and wellbeing in general. The consumption of a balanced diet is essential for overall good health, and a lack of equilibrium can lead to malnutrition, prenatal death, obesity, osteoporosis and bone fractures, coronary heart diseases (CHD), idiopathic hypercalciuria, diabetes, and many other conditions. CHD, osteoporosis, malnutrition, and obesity are extensively discussed in the literature, although there are fragmented findings in the realm of kidney stone diseases (KSD) and their correlation with food intake. KSD associated with hematuria and renal failure poses an increasing threat to healthcare infrastructures and the global economy, and its emergence in the Indian population is being linked to multi-factorial urological disorder resulting from several factors. In this realm, epidemiological, biochemical, and macroeconomic situations have been the focus of research, even though food intake is also of paramount importance. Hence, in this article, we review the corollary associations with the consumption of diverse foods and the role that these play in KSD in an Indian context

Frequency-induced morphology alterations in micro confined biological cells

by Hritwick Banerjee, Bihas Roy, Kaustav Chadhury and Babji Srinivasa

Soft, stretchable optical fibers via thermal drawing

Optical fibers that can sustain large elastic deformations are promising building blocks in soft robotics, medical and wearable devices, and advanced textiles. Thus far, however, the fabrication methods developed for soft optical fibers have remained unmatured. Here, we present thermal drawing as a materials and processing platform to fabricate 10s of meters-long soft, multi-material optical fibers with intriguing architectures. It offers unprecedented opportunities to realize step-index soft optical fibers, as well as photonic crystal fibers for transmission, reflection, and sensing

Correction: Bhagat, S.; et al. Deep Reinforcement Learning for Soft, Flexible Robots: Brief Review with Impending Challenges. Robotics 2019, 8, 4

The authors wish to make the following corrections to this paper [1]: In Figure 1 of this paper [...

Strong, Ultrastretchable Hydrogel-Based Multilayered Soft Actuator Composites Enhancing Biologically Inspired Pumping Systems

10.1002/adem.202100121Advanced Engineering Materials2310210012