Search results for "observer"
showing 5 items of 345 documents
Real Time Localization Systems for autonomous navigation: Modelling, Analysis and Control
2021
Questo lavoro di tesi riguarda la derivazione di osservatori ibridi dello stato, analisi e controllo, di sistemi di localizzazione e navigazione in tempo reale (RTLS). In particolare, il framework dei sistemi ibridi è stato utilizzato per tener conto delle dinamiche continue e discrete coinvolte nel processo di stima e della natura sporadica e tempo randomica delle misure provenienti da vari sensori di distanza e/o inerziali. Analisi di convergenza sono state effettuate per dimostrare la stabilità delle soluzioni proposte e la capacità di filtraggio dei rumori presenti nelle misure. Il presente lavoro è corredato dai risultati delle prove sperimentali di laboratorio a conferma della validit…
Active disturbance rejection control of linear induction motor
2017
This paper proposes the theoretical framework and the experimental application of the active disturbance rejection control to linear induction motors. Such a nonlinear control (ADRC) technique can be viewed as a particular kind of input-output linearization control, where the nonlinear transformation of the state is not computed by means of the model, but it is estimated online. Such an approach permits to cope with unmodelling dynamics, as well as uncertainty in the knowledge of the model parameters and exogenous disturbances. The effectiveness of the proposed ADRC control law has been verified both by numerical simulations and experimentally on a suitably developed test setup. Moreover, t…
Stiffness Estimation and Adaptive Control for Soft Robots
2022
Nonostante la sorprendente crescita nello sviluppo dei robot ispirati alla natura, tra cui i cosiddetti soft robot, il potenziale di questi sistemi, che hanno intrinseche capacità di adattamento, non è ancora stato sfruttato a pieno. La ricerca ha principalmente considerato il controllo in retroazione della posizione dei giunti del robot, lasciando la gestione della cedevolezza di questi ultimi ancora in anello aperto. Peraltro, le attuali limitazioni nel processo di produzione degli attuatori a cedevolezza variabile e l'inevitabile variabilità nel tempo degli elementi elastici costitutivi, i quali sono soggetti ad usura e deformazione plastica, rendono il problema della determinazione prec…
Is it possible to understand a book missing a quarter of the letters? Unveiling the belowground species richness of grasslands
2022
Abstract Knowledge of species richness patterns in plant communities is biased toward its hidden belowground part and is derived only from the part visible aboveground. Studies on the relationship of the above- to belowground parts of plant communities suffer from the lack of a consistent and uniform approach to assess their taxonomic composition, particularly in species-rich ecosystems. This study described the proportion between above- and belowground parts of vegetation in three grassland types along with the environmental factors that affect them, using eDNA metabarcoding and an observer survey. The internal transcribed spacer 2 (ITS2) region was used to analyze the total plant richness…
The effects of antimicrobial sprays and mouthrinses on supragingival plaque regrowth: a comparative study.
2006
BACKGROUND: Due to the side effects of chlorhexidine digluconate (CHX) mouthrinsing, a spray has been proposed as an alternative method of CHX delivery to the oral cavity. The aim of this study was to investigate the plaque inhibitory effects of CHX, cetylpyridinium chloride (CPC), and triclosan (TRN) delivered by sprays and mouthrinses. METHODS: The study was an observer-masked, randomized cross-over design balanced for carryover effects, involving 15 healthy volunteers in a 4-day plaque regrowth model. Products being tested (0.2% CHX, 0.12% CHX, 0.05% CPC, and 0.03% TRN) were used both as sprays and mouthrinses. A saline solution served as a negative control. On day 1, subjects received p…