93-XX SYSTEMS THEORY; CONTROL (For optimal control, see 49-XX)
Refine
Document Type
- Article (1)
- Doctoral Thesis (1)
Language
- English (2)
Has Fulltext
- yes (2)
Keywords
- ROS (1)
- collision avoidance (1)
- deadlock (1)
- distributed model predictive control (1)
- motion control (1)
- multiple robotic manipulators (1)
- robotic manipulators (1)
Faculty / Organisational entity
Mechanistic disease spread models for different vector borne diseases have been studied from the 19th century. The relevance of mathematical modeling and numerical simulation of disease spread is increasing nowadays. This thesis focuses on the compartmental models of the vector-borne diseases that are also transmitted directly among humans. An example of such an arboviral disease that falls under this category is the Zika Virus disease. The study begins with a compartmental SIRUV model and its mathematical analysis. The non-trivial relationship between the basic reproduction number obtained through two methods have been discussed. The analytical results that are mathematically proven for this model are numerically verified. Another SIRUV model is presented by considering a different formulation of the model parameters and the newly obtained model is shown to be clearly incorporating the dependence on the ratio of mosquito population size to human population size in the disease spread. In order to incorporate the spatial as well as temporal dynamics of the disease spread, a meta-population model based on the SIRUV model was developed. The space domain under consideration are divided into patches which may denote mutually exclusive spatial entities like administrative areas, districts, provinces, cities, states or even countries. The research focused only on the short term movements or commuting behavior of humans across the patches. This is incorportated in the multi-patch meta-population model using a matrix of residence time fractions of humans in each patches. Mathematically simplified analytical results are deduced by which it is shown that, for an exemplary scenario that is numerically studied, the multi-patch model also admits the threshold properties that the single patch SIRUV model holds. The relevance of commuting behavior of humans in the disease spread has been presented using the numerical results from this model. The local and non-local commuting are incorporated into the meta-population model in a numerical example. Later, a PDE model is developed from the multi-patch model.
A flexible operation of multiple robotic manipulators operating in a dynamic environment
requires online trajectory planning to ensure collision-free trajectories. In this work, we propose a real-time
capable motion control algorithm, based on nonlinear model predictive control, which accounts for static and
dynamic obstacles. The proposed algorithm is realized in a distributed scheme, where each robot optimizes its
own trajectory with respect to the related objective and constraints.We propose a novel approach for collision
avoidance between multiple robotic manipulators, where each robot accounts for the predicted movement of
the neighboring robots. Additionally, we propose a method to reliably detect and resolve deadlocks occurring
in a setup of multiple robotic manipulators.We validate our approach on pick and place scenarios involving
multiple robotic manipulators operating in a common workspace in a realistic simulation environment
set up in Gazebo. The robots are controlled using the Robot Operating System. Our approach scales up
to 4 manipulators and computes a path for each robot in a simultaneous pick and place operation in 94% of
all investigated cases without deadlock detection and 100 % of cases with the proposed deadlock resolution
algorithm. In contrast, the investigated conventional path planners, such as PRM, PRM*, CHOMP and RRTConnect,
successfully plan a trajectory in at most 54% of all investigated cases for a simultaneous operation
of 4 robotic manipulators hindering their application in setups of multiple manipulators.