Insect Powered Micro Air Vehicles And Centimeter Scale High Energy Density Pneumatic Sources
The flight times of traditional Micro-Air-Vehicles (MAVs) are limited by low energy density of batteries at small scale. On the other hand insects outperform MAVs in terms of flight time due to the higher energy density of carbohydrates and fat. Some of the most successful flapping wing MAVs have continuous flight time of only about 15 minutes, while some insects can have continuous flight times as high as three hours. Motivated by this, we have worked towards realization of insect powered MAVs. This dissertation presents successful navigation of moths, using light-weight and low-power actuators, demonstrating insect powered MAVs (IPMAV) for the first time. These MAVs can fly for long periods of time, consuming only a small fraction (1%) of power compared to purely mechanical MAVs. Untethered flight control of Balloon enabled IPMAVs was achieved using force based techniques. Flight control distances of over 1km and flight times of 40 minutes were achieved. This dissertation also reports the first use of carbon-fiber composite Centimeter-Scale High Pressure-Vessel (CSHPV) applied to MEMS actuators. We present the design, fabrication and testing of MEMS compatible CSHPV and valves with pneumatic energy densities exceeding those of the traditional Lithium battery and electromechanical actuator combination. The pneumatic power sources can provide direct mechanical power to move mechanical elements, enabling pathway for highly efficient operation. The 1-2 cc pressure vessels with burst pressures as high as 3250 bar were achieved corresponding to an energy density of 20.5 Wh/Kg, comparable to 50 Wh/Kg of Lithium batteries with similar volumes. A novel microfluidic interface to the CSHPV was realized using glass capillaries that provide high fluidic resistance at high pressures. Electromagnetic coil valves were fabricated to control CO2 flow from 10-20 micron diameter glass capillaries that could actuate surface micromachined polysilicon micromotors.