PRODUCTS
Bio-inspired Aerial Robot: The Quad Flapper
Biological flyers represent a gold mine of scientifically-rich problems: a well-spring of knowledge and inspiration for engineers and scientists. The nonlinear, time-varying wing dynamics interact with body flight dynamics and unsteady flows in a synergistic way that results in astounding flight capabilities. For example, some insects can thrust up to five times their weights, while others have been observed to perform turning maneuvers of greater than 3000 deg/s, with less than a 30 ms delay, in situations that demand agility, such as chasing a potential mate. In normal everyday flight, some birds may experience up to 14 g accelerations in super-maneuverable tasks, while the maneuverability of the most advanced fighter airplanes cannot exceed 8 − 9 g. This huge potential inspired engineers to design flapping wing micro-air-vehicles (FWMAVs) or Bio-inspired Flying Robots (BIFRs).
Flapping flight has been a puzzle for aeronautical engineers and biologists for a century, particularly its flight stability. From an aeronautical engineering perspective, a hovering insect looks like a helicopter; both are unstable at the hovering position. Since a helicopter is equipped with a feedback control system that stabilizes its hovering, aeronautical engineers and biologists initially thought that the insect brain has a similar "autopilot" that continuously monitors its attitude and corrects for any disturbance. The main difference, however, between a hovering insect and a helicopter is that the former does not remain stationary in place during hover. Rather, it goes back and forth, up and down; it oscillates in all directions because of the wing back-and-forth flapping.
Our collaborative team recently revealed a new lesson from Nature on the fascinating stability characteristics of insect flight. It is well-known to dynamicists that an oscillatory (vibratory) system may gain stability for free through a phenomenon called vibrational stabilization. The most famous example is the inverted pendulum with an oscillating pivot; this unstable pendulum gains stability for free due to the oscillation of the pivot:
So, our recent study reveals that the natural oscillations of an insect’s body around the hovering position naturally stabilizes its unstable flight dynamics through vibrational stabilization, similar to the inverted pendulum. Watch this 6-mins documentary about our discovery:
See the BBC Arabic report on our discovery and its potential use in drones:
Based on this scientific discover, we developed a unique flapping drone: the Quad flapper -
Gauss Flow Sim
Gauss Flow Sim is a CFD software for low-speed applications (incompressible flows) such as airplanes near T/O and landing, low-speed drones, wind turbines, submarines, etc. It is 5 times faster than the best state-of-the-art solver in this category.
It is based on the Principle of Minimum Pressure Gradient (PMPG), discovered by our chief scientist and his team (Video). The PMPG turns the fluid mechanics problem into an optimization problem (instead of solving Navier-Stokes’ equation): a convex quadratic programming problem, whose solution is extremely more efficient than the best solver which adopts pressure-velocity coupling.
Aircraft System Identification Toolbox (ASIT)
The ASIT tool is a Matlab-based software predicts the airplane dynamical characteristics (stability coefficients and control coefficients, natural frequencies and damping coefficients about the 3 axes) from flight measurements.
Model-Agnostic Maneuver Control Software
Simulation of various maneuvers is a routine task performed by several groups (e.g., flight mechanics, controls, system engineering, etc) at airplane manufacturers. It is indispensable for pre-certification checks and for exploring the capability of the airplane.
These maneuvers span wide range from pull-up, to vertical loop, to barrel roll, to cross-wind landing, etc. So, a typical recurrent task for the engineers of these groups is to find the necessary control inputs that can execute a specific maneuver. This task is quite challenging and typically done by trial-and-error, consuming a considerable time from engineers. There are several techniques to simulate these maneuvers; perhaps, inverse simulation has been one of the standard techniques in this regard.
However, it is highly model-dependent and lacks generality. We developed a novel method based on optimal control formulation to achieve this task. The Maneuver Control Software (MCS) is a Matlab-based tool that performs desired maneuvers for a generic airplane.
