A Map-Reduce Parallel Approach to Automatic Synthesis of Control Software

Many Control Systems are indeed Software Based Control Systems, i.e. control systems whose controller consists of control software running on a microcontroller device. This motivates investigation on Formal Model Based Design approaches for automatic synthesis of control software. Available algorithms and tools (e.g., QKS) may require weeks or even months of computation to synthesize control software for large-size systems. This motivates search for parallel algorithms for control software synthesis. In this paper, we present a Map-Reduce style parallel algorithm for control software synthesis when the controlled system (plant) is modeled as discrete time linear hybrid system. Furthermore we present an MPI-based implementation PQKS of our algorithm. To the best of our knowledge, this is the first parallel approach for control software synthesis. We experimentally show effectiveness of PQKS on two classical control synthesis problems: the inverted pendulum and the multi-input buck DC/DC converter. Experiments show that PQKS efficiency is above 65%. As an example, PQKS requires about 16 hours to complete the synthesis of control software for the pendulum on a cluster with 60 processors, instead of the 25 days needed by the sequential algorithm in QKS.Comment: To be submitted to TACAS 2013. arXiv admin note: substantial text overlap with arXiv:1207.4474, arXiv:1207.409

Development of a polymeric piezoelectric C-block actuator using hybrid optimization technique

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/76810/1/AIAA-13031-236.pd

A performance comparison of robust adaptive controllers: linear systems

We consider robust adaptive control designs for relative degree one, minimum phase linear systems of known high frequency gain. The designs are based on the dead-zone and projection modifications, and we compare their performance w.r.t. a worst case transient cost functional with a penalty on the L∞ norm of the output, control and control derivative. We establish two qualitative results. If a bound on the L∞ norm of the disturbance is known and the known a priori bound on the uncertainty level is sufficiently conservative, then it is shown that a dead-zone controller outperforms a projection controller. The complementary result shows that the projection controller is superior to the dead-zone controller when the a priori information on the disturbance level is sufficiently conservative

Systematische Untersuchungen zur Bestimmung von Tensiden in Flusssedimenten

The work had the aim to develop and test a comprehensive concept for the determination of tensides in aquatic systems. In monitoring studies, the sediments preferably used for this purpose are those that are capable of enriching substances because of their large surface and special sorption properties, thus representing extremely valuable indicators of the pollution of running waters. Therefore the investigations focused mainly on river sediments. (orig./SR)Das Ziel der vorliegenden Arbeit bestand in der Entwicklung und Erprobung eines umfassenden Konzepts zur Bestimmung von Tensiden in aquatischen Systemen. Bei Monitoring-Studien werden hierfuer bevorzugt Sedimente verwendet, die auf Grund ihrer grossen Oberflaeche und ihrer besonderen Sorptionseigenschaften Substanzen anreichern koennen und damit aeusserst wertvolle Indikatoren fuer die Belastung von Fliessgewaessern darstellen. Aus diesem Grund konzentrierten sich die Untersuchungen im wesentlichen auf Flusssedimente. (orig./SR)Available from TIB Hannover: RA 831(3265) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman

Pup-cannibalism in rodents

The design of a robust autoland controller using an optimization based design process is described. A modular controller architecture is developed first. Inner loops are based on Dynamic Inversion, speed and longitudinal path tracking loops are based on the Total Energy Control System. Functions for lateral path tracking, ILS guidance, flare and runway alignment are based on classical PID structures. The free parameters in the controller functions are tuned using multi-objective optimization. Performance criteria are directly derived from the imposed design requirements and computed from linear or nonlinear analysis (e.g. eigenvalues, simulations). Robustness is addressed via a multi-model approach, via optimization criteria (e.g. gain/phase margins), and, as a new contribution, via statistical criteria computed from on-line Monte-Carlo analysis. The design process and selected architecture have been applied to a wide-body as well as a small passenger aircraft to demonstrate controller robustness and efficiency of the process. In both cases, JAR-AWO specifications had to be met. The latter design was successfully flight tested