Motion planning for geometric models in data visualization

Interaktivní geometrické modely pro simulaci přírodních jevů (LH11006)Pokročilé grafické a počítačové systémy (SGS-2016-013)A finding of path is an important task in many research areas and it is a common problem solved in a wide range of applications. New problems of finding path appear and complex problems persist, such as a real-time plan- ning of paths for huge crowds in dynamic environments, where the properties according to which the cost of a path is evaluated as well as the topology of paths may change. The task of finding a path can be divided into path planning and motion planning, which implicitly respects the collision with surroundings in the environment. Within the first group this thesis focuses on path planning on graphs for crowds. The main idea is to group members of the crowd by their common initial and target positions and then plan the path for one representative member of each group. These representative members can be navigated by classic approaches and the rest of the group will follow them. If the crowd can be divided into a few groups this way, the proposed approach will save a huge amount of computational and memory demands in dynamic environments. In the second area, motion planning, we are dealing with another problem. The task is to navigate the ligand through the protein or into the protein, which turns out to be a challenging problem because it needs to be solved in 3D with the collision detection

How do learners respond to computer based learning material which has been designed to suit their particular learning style

The development of ICT in education has changed the nature of people's learning. The evolution of Computer Based Learning (CBL) to virtual learning has had a huge effect on learning methodology. Learning theories from behaviourism, cognitivism and constructivism have been re-assessed. This study explored students' feedback and experiences when using CBL material which has been adapted to particular learning styles. Studies show that individuals learn in different ways. They have different preferences in collecting, organizing and delivering information. These differences impact on learning outcomes. The framework in this study concerns itself with modal preferences known as the VARK Model. The study focuses on CBL material which has been designed for learning new software. This learning material was designed with four different learning routes to appeal to those with dominant Visual, Aural, Reading and Kinaesthetic preferences respectively. The learning package was called the MINDs learning system. Respondents involved were student teachers in two Universities in the UK and Malaysia. Sixty two respondents agreed to participate interviews and in trialling courseware. Data was collected through questionnaire, survey, interview and observation. Quantitative and qualitative data was analysed descriptively, triangulation of the findings was carried out and conclusions were drawn. Findings from the study show that learning styles instruments measure general preferences rather than offering an indication of the specific context in which learning takes place. Matching learning material with particular learning styles did not significantly increase motivation, comprehension or have a major impact on learning. However, learners are aware of having learning styles and found that learning with suited learning preferences made them feel more comfortable. Recommendations were put forward for future research to design and develop a 'new type' of CBL material which takes into account individual learning preferences

REACTIVE MOTION REPLANNING FOR HUMAN-ROBOT COLLABORATION

Negli ultimi anni si è assistito a un incremento significativo di robot che condividono lo spazio di lavoro con operatori umani, per combinare la rapidità e la precisione proprie dei robot con l'adattabilità e l'intelligenza umana. Tuttavia, questa integrazione ha introdotto nuove sfide in termini di sicurezza ed efficienza della collaborazione. I robot devono essere in grado di adattarsi prontamente ai cambiamenti nell'ambiente circostante, come i movimenti degli operatori, adeguando in tempo reale il loro percorso per evitare collisioni, preferibilmente senza interruzioni. Inoltre, nelle operazioni di collaborazione tra uomo e robot, le traiettorie ripianificate devono rispettare i protocolli di sicurezza, al fine di evitare rallentamenti e fermate dovute alla prossimità eccessiva del robot all'operatore. In questo contesto è fondamentale fornire soluzioni di alta qualità in tempi rapidi per garantire la reattività del robot. Le tecniche di ripianificazione tradizionali tendono a faticare in ambienti complessi, soprattutto quando si tratta di robot con molti gradi di libertà e numerosi ostacoli di dimensioni considerevoli. La presente tesi affronta queste sfide proponendo un nuovo algoritmo sampling-based di ripianificazione del percorso per manipolatori robotici. Questo approccio sfrutta percorsi pre-calcolati per generare rapidamente nuove soluzioni in poche centinaia di millisecondi. Inoltre, incorpora una funzione di costo che guida l'algoritmo verso soluzioni che rispettano lo standard di sicurezza ISO/TS 15066, riducendo così gli interventi di sicurezza e promuovendo una cooperazione efficiente tra uomo e robot. Viene inoltre presentata un'architettura per gestire il processo di ripianificazione durante l'esecuzione del percorso del robot. Infine, viene introdotto uno strumento software che semplifica l'implementazione e il testing degli algoritmi di ripianificazione del percorso. Simulazioni ed esperimenti condotti su robot reali dimostrano le prestazioni superiori del metodo proposto rispetto ad altre tecniche popolari.In recent years, there has been a significant increase in robots sharing workspace with human operators, combining the speed and precision inherent to robots with human adaptability and intelligence. However, this integration has introduced new challenges in terms of safety and collaborative efficiency. Robots now need to swiftly adjust to dynamic changes in their environment, such as the movements of operators, altering their path in real-time to avoid collisions, ideally without any disruptions. Moreover, in human-robot collaborations, replanned trajectories should adhere to safety protocols, preventing safety-induced slowdowns or stops caused by the robot's proximity to the operator. In this context, quickly providing high-quality solutions is crucial for ensuring the robot's responsiveness. Conventional replanning techniques often fall short in complex environments, especially for robots with numerous degrees of freedom contending with sizable obstacles. This thesis tackles these challenges by introducing a novel sampling-based path replanning algorithm tailored for robotic manipulators. This approach exploits pre-computed paths to generate new solutions in a few hundred milliseconds. Additionally, it integrates a cost function that steers the algorithm towards solutions that strictly adhere to the ISO/TS 15066 safety standard, thereby minimizing the need for safety interventions and fostering efficient cooperation between humans and robots. Furthermore, an architecture for managing the replanning process during the execution of the robot's path is introduced. Finally, a software tool is presented to streamline the implementation and testing of path replanning algorithms. Simulations and experiments conducted on real robots demonstrate the superior performance of the proposed method compared to other popular techniques

Static and Dynamic Path Planning Using Incremental Heuristic Search

Path planning is an important component in any highly automated vehicle system. In this report, the general problem of path planning is considered first in partially known static environments where only static obstacles are present but the layout of the environment is changing as the agent acquires new information. Attention is then given to the problem of path planning in dynamic environments where there are moving obstacles in addition to the static ones. Specifically, a 2D car-like agent traversing in a 2D environment was considered. It was found that the traditional configuration-time space approach is unsuitable for producing trajectories consistent with the dynamic constraints of a car. A novel scheme is then suggested where the state space is 4D consisting of position, speed and time but the search is done in the 3D space composed by position and speed. Simulation tests shows that the new scheme is capable of efficiently producing trajectories respecting the dynamic constraint of a car-like agent with a bound on their optimality.Comment: Internship Repor

Flexible Informed Trees (FIT*): Adaptive Batch-Size Approach for Informed Sampling-Based Planner

In modern approaches to path planning and robot motion planning, anytime almost-surely asymptotically optimal planners dominate the benchmark of sample-based planners. A notable example is Batch Informed Trees (BIT*), where planners iteratively determine paths to groups of vertices within the exploration area. However, maintaining a consistent batch size is crucial for initial pathfinding and optimal performance, relying on effective task allocation. This paper introduces Flexible Informed Tree (FIT*), a novel planner integrating an adaptive batch-size method to enhance task scheduling in various environments. FIT* employs a flexible approach in adjusting batch sizes dynamically based on the inherent complexity of the planning domain and the current n-dimensional hyperellipsoid of the system. By constantly optimizing batch sizes, FIT* achieves improved computational efficiency and scalability while maintaining solution quality. This adaptive batch-size method significantly enhances the planner's ability to handle diverse and evolving problem domains. FIT* outperforms existing single-query, sampling-based planners on the tested problems in R^2 to R^8, and was demonstrated in real-world environments with KI-Fabrik/DARKO-Project Europe.Comment: 8 pages,6 figure