This paper reviews some of the important technical barriers that must be overcome to achieve truly efficient flying adaptive micro air vehicles (MAVs). As defined by the Defense Advanced Research Agency (DARPA), MAVs are vehicles with no length dimension greater than 6 inches. These vehicles typically weigh less than 100 grams and some can fly for approximately 30 minutes. Over the past decade significant progress has been made in developing these small-scale mechanical flying machines. However, there is still much work to be done if these vehicles are to approach the efficiency and performance of biological fliers. This paper reviews the status of current miniature mechanical flying machines and compares their performance with common biological flyers such as birds, and small insects. This comparison reveals that advances in aerodynamic efficiency, lightweight and adaptive wing structures, energy conversion/propulsion systems and flight control are required to match or exceed the performance of natureaEURO (TM)s great flyers.

First Published in 2017. Routledge is an imprint of Taylor & Francis, an Informa company.

The twenty-first century could be called the 'Multifunctional Materials Age'. The inspiration for multifunctional materials comes from nature, and therefore these are often referred to as bio-inspired materials. Bio-inspired materials encompass smart materials and structures, multifunctional materials and nano-structured materials. This is a dawn of revolutionary materials that may provide a 'quantum jump' in performance and multi-capability. This book focuses on smart materials, structures and systems, which are also referred to as intelligent, adaptive, active, sensory and metamorphic. The purpose of these materials from the perspective of smart systems is their ability to minimize life-cycle cost and/or expand the performance envelope. The ultimate goal is to develop biologically inspired multifunctional materials with the capability to adapt their structural characteristics (such as stiffness, damping and viscosity) as required, monitor their health condition, perform self-diagnosis and self-repair, morph their shape and undergo significant controlled motion over a wide range of operating conditions.

Gamera: A Human Powered Helicopter – In Pursuit of an Aviation Milestone is an engineering history of the human powered helicopter creatively designed, skillfully built, and courageously flown by students of the University of Maryland. A majority of students were from the Department of Aerospace Engineering and the A. James Clark School of Engineering, joined by enthusiastic volunteers from other departments. Together, they conquered an ambitious aviation milestone: vertical flight by human power. The project was spread over four years and involved the efforts of over 100 undergraduate and 30 graduate students. Four distinct versions of the aircraft (Gamera I, Gamera II, Gamera IIXR, and Gamera IID) evolved during the program with increasing refinements in design, fabrication, and testing. Each version incorporated improvements that helped to obtain better performance, lower weight, and skilled innovations for improving the stability of the helicopter. Gamera still holds world records for human powered flight endurance of 97 seconds and height of 10.5 ft, approved by the FAI (Fédération Aéronautique Internationale, World Aeronautical Federation), as well the Guinness Book of World Records. The Gamera project excited the imagination of a great number of people and was covered by several national media outlets including print, television, and social media. The Gamera project was subsequently transformed from a human powered helicopter to a solar powered helicopter. This technical history is accessible to a general engineering audience at the college junior level. The concepts of helicopter aerodynamics, aeromechanics, and composite structures are explained using a minimum of jargon, without oversimplifying the explanations.