This paper describes the development of skeletal mechanisms and wings for the electromechanical emulation of mesoscale flapping flight. Specifically, three piezoelectrically actuated flexure-based mechanisms are described that transform the linear output of piezoelectric unimorph actuators into single-degree-of-freedom flapping motion, and experimental results are described that characterize their performance. Additionally, efforts in the development of aeroelastically tailored wings are described, and data is presented that characterizes how the ratio of bending to torsional natural frequencies of the wing influences wing lift and efficiency.

Low speed aerodynamics and its application to microflight and microaerial vehicles is an interesting problem. Small stout wings with small areas result in low Reynolds numbers. For Re's below iO conventional fixed wing flight is no longer possible because drag becomes the dominant force. However it is possible to induce lift using those drag forces in the same manner as some birds and insects. Flapping is a good choice for microaerial vehicles since it is a highly efficient way to produce flight and power consumption is a major concern. Both insects and birds use a complex elastodynamic system that only requires excitation at its natural frequency or some lower harmonic. The actuation device presented is based on the same flight principle of insects and small birds. It is a solid-state, resonating, elastodynamic system excited by a piezoelectric actuator. It is composed oftwo major components. The first component is a solid-state flexure mechanism that is used to amplify the piezoceramic output and produce the flapping motion. The second component is the piezoelectric actuator. Since piezoceramics are capacitive and posses a high energy density and efficiency they can be used to excite the device and induce a flapping motion with low power losses. This allows for long distance flights that require little energy. The complex dynamics ofthe device involves not only the mechanics ofthe actuator and flexure mechanism but the interaction of the wing and the air and the actuators driving electronics. The resulting device is an electromechanically tuned resonating microrobot actuator.

No abstract

Inertially Actuated Jumping Robots (IAJR) provide a promising new means of locomotion. The difficulty of IAJR is found in the hybrid nature of the ground contact/flying dynamics. Recent research studies in our Systems Lab have provided a family tree of inertially actuated locomotion systems. The proposed Tapping Robot is the most prompt member of this tree. In this paper, a feedback linearization controller is introduced to provide controllability given the 3-dimensional motion complexity. The research objective is to create a general controller that can regulate the locomotion of Inertially Actuated Jumping Robots. The expected results can specify a desired speed and/or jump height, and the controller ensures the desired values are achieved. The controller can achieve the greatest response for the Basketball Robot at a maximum jump height of 0.25 m, which is greater than the former performance with approximately 0.18 m. The design paradigm used on the Basketball Robot was extended to the Tapping Robot. The Tapping Robot achieved a stable average forward velocity of 0.0773 m/s in simulation and 0.157 m/s in experimental results, which is faster than the forward velocity of former robot, Pony III, with 0.045 m/s.

No abstract