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This study investigates the aerodynamic performance of different flying sensors inspired by dandelion seeds, using COMSOL Multiphysics CFD simulation. Dandelion seeds are well known for their ability to remain suspended in the air for extended periods due to their lightweight structure, higher porosity, high drag, and the formation of a separated vortex ring (SVR) above the seed. Mimicking this behavior, five 2D and one 3D geometry were developed and analyzed first through steady-state simulations to explore how different design geometries influence passive flight performance. The primary aim is to identify an optimized structure that can achieve slower descent when realized from an altitude by drones for remote sensing. Steady-state results showed that although the drag coefficient generally decreased with increase in Reynolds numbers, porosity did not exhibit a constant trend across all designs. In some cases, geometries with lower porosity outperformed more porous ones. This may be due to their structural differences. SVR was observed in all designs. However, the distance between these SVR and geometry’s surface was small. While steady-state results give a fair indication of the aerodynamic behavior and relative performances of the various geometries, there are limitations. To address this, transient drop tests, currently under verification, will give a better understanding of the performances of these designs from which the best will be selected. 

This study aimed to investigate the aerodynamic and thermal behavior of dandelion diaspore analogs to explore the effect of coloration on the overall flow field. To do so, computational fluid dynamics simulations were performed on simplified porous disk models across varying absorptivities under steady-state and transient conditions. By coupling heat transfer and fluid dynamics, the simulations captured the influence of thermal gradients on stable vortex ring formation and overall drag forces. Results showed that increased surface temperature, caused by higher absorptivity, enhanced buoyancy forces, disrupted vortex ring formation, and elevated drag coefficients. Conversely, white-colored analogs exhibited lower thermal loading and reduced aerodynamic resistance. While the current model employed a rigid, porous disk approximation, it provides valuable insights into the effects on the fluid flow of unmanned, dandelion-inspired micro aerial vehicles (MAVs). 

The paper outlines the design, prototyping, and simulation processes involved in creating a compact radio frequency (RF) backscatter communication system, powered by Organic Photovoltaic (OPV) cells. This system is integral to a mine rescue operation, particularly useful in scenarios where miners are trapped due to accidents. In such situations, a rescue drone, equipped with a searchlight and the discussed communication system, takes the lead in the assisted escape mission for miners. The drone establishes duplex communication with the miners through a battery-free, wearable transponder device. Initial experiments employing a RF backscatter testbed - which utilizes both software-defined radios and OPV cells - were conducted. These preliminary tests were crucial for assessing the conditions necessary for successful backscatter communication, as well as for evaluating the energy-harvesting performance of the system. Findings from these experiments indicate that the device can operate battery-free, powered solely by OPV cells, even under low illuminance levels of less than 75 lux. In the pursuit of crafting the device in a compact form, a co-design initiative was launched. This effort focused on developing a meander dipole antenna in tandem with the OPV cells, targeting a resonant frequency of 912 MHz. Simulation results, obtained from ANSYS HFSS, revealed significant changes in antenna impedance and S parameters yet minimal impact on the radiation pattern of the antenna with the integration of the layered OPV structure. 

This paper aims to design a jellyfish-inspired robot for the exploration of Venus’ atmosphere. Venus’ hostile environment necessitates different methods for planetary analysis than that of Mars or Earth. In this research, an established jellyfish-inspired drone design is modified to take advantage of Venus’ dense atmosphere for the purpose of upper atmospheric exploration. The original design uses modified Stephenson-I 6-Bar linkages to actuate a soft skin to produce thrust in a fluid, similar to the movement of a jellyfish’s bell; this research compares the original actuator design to 3 new designs based on the 6-Bar and 4-Bar linkages. In addition, a Crank mechanism to change the profile of the balloon is proposed, and the resulting effect on the drag force is compared between the original spherical profile and the modified oblong profile. These mechanisms will allow the robot to maximize its operational time in Venus’s atmosphere. In combination with the design of the jellyfish-inspired robot is the proposal of flagellate-inspired robots that rely on Venus's strong winds to power its host of sensors. 

Agility, robustness, endurance, and sustainability are the main challenges of the current distributed systems for ocean objects identification. Nowadays, developing a novel marine observation network to help identify threats and to provide both an early warning and data for forecasting models is a priority of marine missions. Autonomous systems, such as underwater robots and drones, can provide worthwhile information from the ocean environment; still, they have challenges associated with endurance, performance, and recovery. Skimming drones cannot be used to perform underwater missions, need a significant amount of energy to take off, and have stability problems due to the constant ocean wave motion. As for underwater swimming robots, they are generally slow and use a significant amount of energy. To this end, there is a need to design some novel bioinspired amphibious concepts that can overcome these challenges. In this paper, a network of distributed hybrid-amphibious robots with energy harvesting capabilities will be presented. This is accomplished through novel robot systems. The Lizard-Spider Octopus-Jellyfish-Rolling Robot (LSOJRR) is one of these novel ideas, which imitates the characteristics of a Golden wheel spider with rolling, jumping, and folding capabilities over the water, a Green Basilisk lizard with running capability over the water, and an octopus with unique underwater propulsion mechanism. The LSOJRR also has applications beyond Earth, and alternative designs of this robot are explored, particularly those involving the dispersal of swarms of smaller robots that also derive their design from biology. All of the designs presented in this paper draw inspiration from nature, and strive to achieve the goal of furthering the development for marine exploration.