Research
Our research revolves around computational issues related to feedback control design. We also enjoy finding further challenges for development of theoretical results in diverse application domains, mainly relying on electrical and electromechanical principles.
AA4CC group has been developing a small research-grade quadrotor (quadcopter, four-rotor helicopter) with the ultimate goal to provide an affordable yet high-performance research platform for investigation of distributed control algorithms for formation flight. The motivation for this R&D activity is twofold.
We focus on stick-slip and ultrasonic piezoelectric microactuators, which achieve long range of motion while keeping high resolution. The former have a slider freely seated on a few piezoelectric legs that are deformed into shear. Applying an assymetric sawtooth-like voltage to the piezos, a sequence of sticking and slicking of the moving slider is created, which results in a net horizontal motion. The latter actuators are based on creating a travelling wave on the surface of a flat piezoelectric material, on which a moving slider is freely placed.
The current mainstream paradigm in control systems is that all the relevant measured variables are brought to a central computer (controller), processed all at once and finally the resulting commands are distributed to the individual actuators. The last decades have witnessed a growing number of applications in which the number of such measured and command variables is huge, easily above a few hundred or thousand signals. With the advent of MEMS devices, more then a hundred thousand variables can easily appear in a given application.
Since 2006 our group has been involved in an R&D activity funded by Ministry of Industry and Trade of the Czech Republic and aimed at development of an inertially stabilized camera platform for aerial surveilance. The coordinator of the project is Czech Air Force and Air Defense Technological Institute (VTÚLaPVO) (a branch of LOM Praha).
We study the problem of distributed planar manipulation by shaping a force field derived from a potential field commanded by an actuator array. The shapes of the spatially continuous fields are commanded through a set of spatially discrete nodes (actuators) such as electrodes in the case of dielectrophroesis, electromagnets in the case of planar magnetic manipulators, or linear piezoelectric actuator in the case of deformable flat surfaces.
We focus on modelling and control of underactuated mechanical systems. Underactuated mechanical systems are mechanical systems having less actuators than the number of degrees of freedom. The simplest underactuated mechanical system is the Acrobot which has two degrees of freedom and one actuator placed between its rigid links. The Acrobot is one of the classical mechanical systems that have been studied extensively in the control area during the past few decades.