More Like this

1. System design for inferring colony-level pollination activity through miniature bee-mounted sensors

   https://doi.org/10.1038/s41598-021-82537-1  

   Abdel-Raziq, Haron M.; Palmer, Daniel M.; Koenig, Phoebe A.; Molnar, Alyosha C.; Petersen, Kirstin H. (December 2021, Scientific Reports)

   Abstract In digital agriculture, large-scale data acquisition and analysis can improve farm management by allowing growers to constantly monitor the state of a field. Deploying large autonomous robot teams to navigate and monitor cluttered environments, however, is difficult and costly. Here, we present methods that would allow us to leverage managed colonies of honey bees equipped with miniature flight recorders to monitor orchard pollination activity. Tracking honey bee flights can inform estimates of crop pollination, allowing growers to improve yield and resource allocation. Honey bees are adept at maneuvering complex environments and collectively pool information about nectar and pollen sources through thousands of daily flights. Additionally, colonies are present in orchards before and during bloom for many crops, as growers often rent hives to ensure successful pollination. We characterize existing Angle-Sensitive Pixels (ASPs) for use in flight recorders and calculate memory and resolution trade-offs. We further integrate ASP data into a colony foraging simulator and show how large numbers of flights refine system accuracy, using methods from robotic mapping literature. Our results indicate promising potential for such agricultural monitoring, where we leverage the superiority of social insects to sense the physical world, while providing data acquisition on par with explicitly engineered systems. 

   more » « less
2. Aeroelastic Characterization of Real and Artificial Monarch Butterfly Wings

   https://doi.org/10.2514/6.2020-2002  

   Twigg, Rachel; Sridhar, Madhu; Pohly, Jeremy A.; Hildebrandt, Nicholas; Kang, Chang-Kwon; Landrum, D Brian; Roh, Kyung-Ho; Salzwedel, Samantha (January 2020, AIAA Scitech 2020 Forum)

   The annual migration of monarch butterflies, Danaus plexippus, from their summer breeding grounds in North America to their overwintering sites in Mexico can span over 4000 kilometers. Little is known about the aerodynamic mechanism behind this extended flight. This study is motivated by the hypothesis that their flapping wing flight is enhanced by fluid-structure interactions. The objective of this study to quantify the aeroelastic performance of monarch butterfly wings and apply those values in the creation of an artificial wing with an end goal of creating a biomimetic micro-air vehicle. A micro-CT scan, force-deflection measurements, and a finite element solver on real monarch butterfly wings were used to determine the density and elastic modulus. These structural parameters were then used to create a monarch butterfly inspired artificial wing. A solidification process was used to adhere 3D printed vein structures to a membrane. The performance of the artificial butterfly wing was tested by measuring the lift at flapping frequencies between 6.3 and 14 Hz. Our results show that the elastic modulus of a real wing is 1.8 GPa along the span and 0.20 GPa along the chord, suggesting that the butterfly wing material is highly anisotropic. Real right forewings performed optimally at approximately 10 Hz, the flapping frequency of a live monarch butterfly, with a peak force of 4 mN. The artificial wing performed optimally at approximately 8 Hz with a peak force of 5 mN. 

   more » « less
3. Bimanual Intravenous Needle Insertion Simulation Using Nonhomogeneous Haptic Device Integrated into Mixed Reality

   https://doi.org/10.3390/s23156697  

   Kim, Jin Woo; Jarzembak, Jeremy; Kim, Kwangtaek (August 2023, Sensors)

   In this study, we developed a new haptic–mixed reality intravenous (HMR-IV) needle insertion simulation system, providing a bimanual haptic interface integrated into a mixed reality system with programmable variabilities considering real clinical environments. The system was designed for nursing students or healthcare professionals to practice IV needle insertion into a virtual arm with unlimited attempts under various changing insertion conditions (e.g., skin: color, texture, stiffness, friction; vein: size, shape, location depth, stiffness, friction). To achieve accurate hand–eye coordination under dynamic mixed reality scenarios, two different haptic devices (Dexmo and Geomagic Touch) and a standalone mixed reality system (HoloLens 2) were integrated and synchronized through multistep calibration for different coordinate systems (real world, virtual world, mixed reality world, haptic interface world, HoloLens camera). In addition, force-profile-based haptic rendering proposed in this study was able to successfully mimic the real tactile feeling of IV needle insertion. Further, a global hand-tracking method, combining two depth sensors (HoloLens and Leap Motion), was developed to accurately track a haptic glove and simulate grasping a virtual hand with force feedback. We conducted an evaluation study with 20 participants (9 experts and 11 novices) to measure the usability of the HMR-IV simulation system with user performance under various insertion conditions. The quantitative results from our own metric and qualitative results from the NASA Task Load Index demonstrate the usability of our system. 

   more » « less
4. uavEE: A Modular, Power-Aware Emulation Environment for Rapid Prototyping and Testing of UAV

   M. Theile, O. Dantsker (January 2018, Proceedings of IEEE International Conference on Embedded and Real-Time Computing Systems and Applications (RTCSA))

   State of the art design and testing of avionics for unmanned aircraft is an iterative process that involves many test flights, interleaved with multiple revisions of the flight management software and hardware. To significantly reduce flight test time and software development costs, we have developed a real-time UAV Emulation Environment (uavEE) using ROS that interfaces with high fidelity simulators to simulate the flight behavior of the aircraft. Our uavEE emulates the avionics hardware by interfacing directly with the embedded hardware used in real flight. The modularity of uavEE allows the integration of countless test scenarios and applications. Furthermore, we present an accurate data driven approach for modeling of propulsion power of fixed-wing UAVs, which is integrated into uavEE. Finally, uavEE and the proposed UAV Power Model have been experimentally validated using a fixed-wing UAV testbed. 

   more » « less
5. Force-Constrained Visual Policy: Safe Robot-Assisted Dressing via Multi-Modal Sensing

   Sun, Zhanyi; Wang, Yufei; Held, David; Erickson, Zackory (April 2024, arxiv.org)

   Robot-assisted dressing could profoundly enhance the quality of life of adults with physical disabilities. To achieve this, a robot can benefit from both visual and force sensing. The former enables the robot to ascertain human body pose and garment deformations, while the latter helps maintain safety and comfort during the dressing process. In this paper, we introduce a new technique that leverages both vision and force modalities for this assistive task. Our approach first trains a vision-based dressing policy using reinforcement learning in simulation with varying body sizes, poses, and types of garments. We then learn a force dynamics model for action planning to ensure safety. Due to limitations of simulating accurate force data when deformable garments interact with the human body, we learn a force dynamics model directly from real-world data. Our proposed method combines the vision-based policy, trained in simulation, with the force dynamics model, learned in the real world, by solving a constrained optimization problem to infer actions that facilitate the dressing process without applying excessive force on the person. We evaluate our system in simulation and in a real-world human study with 10 participants across 240 dressing trials, showing it greatly outperforms prior baselines. 

   more » « less