Stability of Mina v2 for Robot-Assisted Balance and Locomotion

The assessment of the risk of falling during robot-assisted locomotion is critical for gait control and operator safety, but has not yet been addressed through a systematic and quantitative approach. In this study, the balance stability of Mina v2, a recently developed powered lower-limb robotic exoskeleton, is evaluated using an algorithmic framework based on center of mass (COM)- and joint-space dynamics. The equivalent mechanical model of the combined human-exoskeleton system in the sagittal plane is established and used for balance stability analysis. The properties of the Linear Linkage Actuator, which is custom-designed for Mina v2, are analyzed to obtain mathematical models of torque-velocity limits, and are implemented as constraint functions in the optimization formulation. For given feet configurations of the robotic exoskeleton during flat ground walking, the algorithm evaluates the maximum allowable COM velocity perturbations along the fore-aft directions at each COM position of the system. The resulting velocity extrema form the contact-specific balance stability boundaries (BSBs) of the combined system in the COM state space, which represent the thresholds between balanced and unbalanced states for given contact configurations. The BSBs are obtained for the operation of Mina v2 without crutches, thus quantifying Mina v2's capability of maintaining balance through the support of the leg(s). Stability boundaries in single and double leg supports are used to analyze the robot's stability performance during flat ground walking experiments, and provide design and control implications for future development of crutch-less robotic exoskeletons

Evaluating the haematological and inflammatory markers in predicting the clinical outcome of COVID-19 patients admitted in a tertiary care hospital of Northern India

Infection with the SARS-CoV-2 virus induces coagulation and stimulates the innate immune system. In ICU patients with COVID-19, nothing is known regarding coagulopathy and the response of inflammation and infection. The effects of SARS-CoV-2 infection on coagulation, infection, and inflammatory indicators, as well as their relationships, were studied. The study took place in Naraina Medical College and Research Centre, a dedicated COVID-19 referral hospital in Northern India, from April to August 2021. This study only included COVID-19 positive hospitalised cases with RT-PCR confirmation. All blood samples were examined for haematological, coagulation, and inflammatory indicators, and mean results were compared between the three patient groups. All patients had elevated d-dimer and FDP levels, notably non-survivors, who had prolonged PT, APTT, INR, and TT, as well as lower PTA and AT, as compared to survivors. Non-survivors were more likely to develop SIC and DIC. All patients' CRP, ESR, serum ferritin, IL-8, and IL-2R levels increased

ihmcrobotics/ihmc-open-robotics-software: 0.11 Release Notes

This release features mostly improvements in the planning behaviors. Unit Test Results https://bamboo.ihmc.us/browse/LIBS-IHMCOPENROBOTICSSOFTWAREFAST-400 3,046 tests in total 1 test failed 20 tests were skipped 311 minutes taken in total. Failing test: VisibilityGraphsFrameworkTest.testDatasetsWithoutOcclusion Atlas Hardware Test Log video: https://youtu.be/rq6zIrvAts4 *** NOTE: The user interface referred to is proprietary software. Please contact IHMC for a license. Robot starts correctly and arm, chest, and head move to their default configurations. LIDAR works in the user interface. REA works and planar regions show up in the user interface. Flat ground walking works well consistently without shaking. Turn in place Walk forwards Walk backwards Walk sideways Chest and head motions can be commanded from the user interface. Arm motions can be commanded from the user interface and arm home options in the interface work as expected. Hands not working Pelvis motions can be commanded from the user interfaces and the center of mass height slider works. Foot motions in the air can be commanded from the user interface. ~1.5 Hz oscillation during single support The robot can run through the final tab motions: Running Man, Karate Kid 1, and Karate Kid 2 repeatedly without falling. Falls over when changing too quickly The robot can reach an object on the ground using the whole body IK from the user interface (F9). When the robot executes a step, the footstep reaches the position specified in the user interface without offset. The robot can walk over the sand test bed. The robot can walk over simple cinders using the planar regions module with a rough terrain footstep planner. The robot can walk over slanted conders when operated by a human. Valkyrie Hardware Test The Valkyrie hardware platform is not supported in this release