Development of a solar powered multirotor micro aerial vehicle.

Rotary-wing aerial vehicles offer manoeuvrability and vertical take-off and landing (VTOL) advantages over fixed-wing systems. Rotary-wing systems do however have comparatively higher energy demands and consequently shorter flight times and therefore a greater energy dependence over their fixed-wing counterparts. Advances in photovoltaic technologies have resulted in significant increases in the specific power (power-to-weight-ratio) of solar cells enabling the design of solar-powered rotary-wing aircraft, and now micro-sized variants. The micro aerial vehicle (MAV) presented, the Micro Solarcopter, is a 0.15 m × 0.15 m × 0.02 m solar-rechargeable radio-controlled aircraft. The 0.071 kg aircraft can fly for an average time of 3.5 min, recharge in approximately 68 min under 1000 W/m2 irradiance at 25 °C and can hibernate for 38 days without sunlight. The paper explores the use of commercially available photovoltaic cells for the purpose of increasing the energy autonomy of multi-rotor MAVs, by enabling them to stay out in the field without returning to base for charging. A working prototype has been presented which incorporates a battery management system, automatic power on and off, low-power sleep mode, and first-person-view (FPV) camera

Development of a solar powered multirotor micro aerial vehicle

Abstract Rotary-wing aerial vehicles offer manoeuvrability and vertical take-off and landing (VTOL) advantages over fixed-wing systems. Rotary-wing systems do however have comparatively higher energy demands and consequently shorter flight times and therefore a greater energy dependence over their fixed-wing counterparts. Advances in photovoltaic technologies have resulted in significant increases in the specific power (power-to-weight-ratio) of solar cells enabling the design of solar-powered rotary-wing aircraft, and now micro-sized variants. The micro aerial vehicle (MAV) presented, the Micro Solarcopter, is a 0.15 m $$\times$$ × 0.15 m $$\times$$ × 0.02 m solar-rechargeable radio-controlled aircraft. The 0.071 kg aircraft can fly for an average time of 3.5 min, recharge in approximately 68 min under 1000 W/m2 irradiance at 25 °C and can hibernate for 38 days without sunlight. The paper explores the use of commercially available photovoltaic cells for the purpose of increasing the energy autonomy of multi-rotor MAVs, by enabling them to stay out in the field without returning to base for charging. A working prototype has been presented which incorporates a battery management system, automatic power on and off, low-power sleep mode, and first-person-view (FPV) camera

A retrospective observational study of liver abscess in children at tertiary care hospital of Ahmedabad city

In developing country like India, liver abscess in children is mostly pyogenic (PLA) in nature. This article aimed to analyze detail parameters of LA of admitted cases in tertiary care hospital of Ahmedabad city. Details of 32 patients From1 month to 14 years age groups were assessed retrospectively over periods of 2 years. The demographic profile, clinical presentation, laboratory and ultra sonographic, microbiological profile, management and outcome of patients were retrieved from case records. All cases had PLA with mean age 6 years and male predominance (64.28%). Under nutrition and enteric fever were only risk factors derived. Fever (93.75%) and abdominal pain (68.75%) were commonest presentation of LA. Leukocytosis found in 62.5% cases with neutrophilic predominance. Majority of LA were single (90.6%), in right lobe of liver (68.8%) with more than 50mm in size. Positivity rate of pus and blood culture in 12.5% and 15.62% cases respectively where staphylococcus aureus is commonest organism.17 cases (53.12%) require antibiotics treatment alone ,14 cases (43.75%) USG guided needler aspiration and 1 case (3%) open surgical drainage with 100%recovery rate. PLA is commonest in children and cryptogenic in origin. Management of LA required multidisciplinary approached include antibiotic and/or USG guided percutaneous needle aspiration