System Architecture MSD16
Paradigm
There are many paradigms available for developing architecture for robotic systems. These paradigms are available in Chapter 8 in the Springer Handbook of Robotics. In this project the paradigm developed at KU Leuven in collaboration with TU Eindhoven and was used. This paradigm is followed at TechUnited.
Layered Approach
This paradigm defines Tasks (blue block) using the objectives set with respect to the context of the project, i.e. what needs to be done. The Skills (yellow block) then define the implementation, i.e. how to these tasks will be completed. The hardware (grey block) or the robots, i.e. the ones who will complete the tasks by implementing the skills are the agents available at the system-architects’ disposal and the choice made to pick certain agents over the other is influenced by system requirements. The system requirements are influenced by a number of factors especially the objectives and the context of the project. Coming back to the agents, they gather information from the environment and this information is first processed (filtered, fused etc.) and then stored in the world model (green block) which allows it to be accessed afterwards. Finally the visualization or the user interface (orange block) is a tool to observe how the system sees the environment.
In the task block, a sub-block is the Task Monitor (highlighted in red within the Task context block). This block was interpreted as a supervisor and a coordinator. It keeps an eye on the tasks and skills. It is possible to have some tasks which are a completed by a series of skills. In such a case it becomes important to schedule skills as these could either have to be executed sequentially or parallelly. It might become important for the system to track which skills have been completed and which need to be executed next. Task control feedback/ feedforward was not taken into consideration in much detail in the system architecture that was developed for this project.
The system architecture derived from the concepts presented in the above-described paradigm can be seen below. Every block but the GUI context is highlighted in this architecture. The Coordinator block interacts with the Supervisor to determine which skills need to be executed and is assisted by the Skill Matcher in picking the right hardware agent best suited to execute the necessary skill. The concept behind the skill matcher is explained in a later section.