Autonomous space exploration using the Turtlebot mobile platform

Cilj diplomske naloge je implementacija avtonomnega raziskovanja prostora na mobilni platformi Turtlebot, ki uporablja razvojno okolje ROS. Implementirali smo raziskovalni algoritem, ki temelji na zaznavi obrobij in njihovi uporabi kot potencialnih raziskovalnih ciljev. Ker pa lahko algoritem pri izbiri raziskovalnih ciljev upošteva različne kombinacije ocen raziskovanja, smo nato preizkušali in primerjali, katera kombinacija ocen omogoča najbolj učinkovito raziskovanje prostora. Različne strategije izbire raziskovalnih ciljev smo ocenjevali in primerjali na podlagi štirih kriterijev ter referenčne strategije, ki naključno izbira raziskovalne cilje. Podatke za primerjavo smo dobili tako, da smo za vsako strategijo opravili deset uspešnih raziskovanj. Te smo nato kot skupine povprečnih vrednosti in odstopanj primerjali med seboj na podlagi referenčne strategije in kriterijev. Implementirali smo modul, ki poleg raziskanosti prostora in časa raziskovanja omogoča tudi beleženje zgodovine premikov in s tem pot raziskovanja, ki jo opravi Turtlebot.The purpose of this undergraduate thesis is to implement the autonomous exploration of space on the Turtlebot mobile platform that uses the ROS development environment. We implemented an exploration algorithm based on the detection and use of frontier regions as potential exploration goals. Since the algorithm is able to choose an exploration goal based on the combination of different assessments, we tested and compared which combination of goal assessments enables the most efficient exploration of a given space. We assessed and compared different strategies of goal setting on the basis of four criteria and a referential strategy which selects its exploration goals randomly. In order to get the data necessary for comparison, we conducted ten successful explorations per strategy and compared them on the basis of the referential strategy and criteria. We implemented our own module, which tracks the amount of space explored and the time spent for exploration, while also documenting the path traveled by the Turtlebot during exploration

Development of Thiophenic Analogues of Benzothiadiazine Dioxides as New Powerful Potentiators of 2‑Amino-3-(3-hydroxy-5-methylisoxazol-4-yl)propionic Acid (AMPA) Receptors

On the basis of the results obtained in previous series of AMPA potentiators belonging to 3,4-dihydro-2<i>H</i>-benzo- and 3,4-dihydro-2<i>H</i>-pyrido-1,2,4-thiadiazine 1,1-dioxides, the present work focuses on the design of original isosteric 3,4-dihydro-2<i>H</i>-thieno-1,2,4-thiadiazine 1,1-dioxides. Owing to the sulfur position, three series of compounds were developed and their activity as AMPA potentiators was characterized. In each of the developed series, potent compounds were discovered. After screening the selected active compounds on a safety in vivo test, 6-chloro-4-ethyl-3,4-dihydro-2<i>H</i>-thieno­[2,3-<i>e</i>]-1,2,4-thiadiazine 1,1-dioxide (<b>24</b>) appeared as the most promising compound and was further evaluated. Its effects on long-term potentiation in vivo and on AMPA-mediated noradrenaline release were measured to predict its potential cognitive enhancing properties. Finally, an object recognition test performed in mice revealed that <b>24</b> was able to significantly enhance cognition, after oral administration, at doses as low as 0.3 mg/kg. This study validates the interest of the isosteric replacement of the benzene or pyridine nuclei by the thiophene nucleus in the ring-fused thiadiazine dioxides class of AMPA potentiators

Positive Allosteric Modulators of 2‑Amino-3-(3-hydroxy-5-methylisoxazol-4-yl)propionic Acid Receptors Belonging to 4‑Cyclopropyl-3,4-dihydro‑2<i>H</i>‑1,2,4-pyridothiadiazine Dioxides and Diversely Chloro-Substituted 4‑Cyclopropyl-3,4-dihydro‑2<i>H</i>‑1,2,4-benzothiadiazine 1,1-Dioxides

Two 4-ethyl-substituted pyridothiadiazine dioxides belonging to α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor positive allosteric modulators were cocrystallized with the GluA2 ligand binding domain in order to decipher the impact of the position of the nitrogen atom on their binding mode at the AMPA receptors. The latter was found to be very similar to that of previously described benzothiadiazine-type AMPA receptor modulators. The affinity of the two compounds for the receptor was determined by isothermal titration calorimetry. Accordingly, the synthesis and biological evaluation of novel 4-cyclopropyl-substituted pyridothiadiazine dioxides was performed and completed with the synthesis of the corresponding chloro-substituted 4-cyclopropyl-3,4-dihydro-2<i>H</i>-benzothiadiazine 1,1-dioxides. The “8-aza” compound <b>32</b> was found to be the most potent pyridothiadiazine-type AMPA receptor potentiator in vitro, whereas the 7-chloro-substituted compound <b>36c</b> emerged as the most promising benzothiadiazine dioxide. Due to proper drug-likeness and low in vivo acute toxicity in mice, <b>36c</b> was chosen for a more complete preclinical evaluation. The compound was able to easily cross the blood–brain barrier. In an in vivo object recognition test with CD1 mice, oral administration of <b>36c</b> was found to significantly improve cognition performance at doses as low as 1 mg/kg