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Aerodynamicists with a vision for birdlike aircraft systems must move beyond steady flow models toward new ways of characterizing motion of agile flight systems. One such system is a fixed-wing aircraft that performs a deep stall maneuver commonly referred to as a perch. Described herein is a mathematical model for perch maneuvers of a small aircraft with fixed, positively cambered wings. The modeling approach does not rely on resource-heavy forms of system identification but rather employs a minimalist approach, whereby insights gleaned from previous high-angleof-attack research are applied to individual components of the aircraft. Using the model that results from this approach, three aggressive, longitudinal perch maneuvers are computer-simulated, and results of the simulations are compared to laboratory flight measurements obtained using high-speed video tracking. Notwithstanding its simplicity, the model predicts position, velocity, and pitch orientation of the aircraft with significant accuracy.

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A mathematical model is developed for a rolling robot with a cylindrically-shaped, elliptical outer surface that has the ability to alter its shape as it rolls, resulting in a torque imbalance that accelerates or decelerates the robot. A control scheme is implemented, whereby angular position and angular velocity are used as feedback to trigger and define morphing actuation. The goal of the control is to direct the robot to follow a given angular velocity profile. Equations of motion for the rolling robot are formulated and solved numerically. Results show that by automatically morphing its shape in a periodic fashion, the rolling robot is able to start from rest, achieve constant average velocity and slow itself in order to follow a desired velocity profile with significant accuracy.