General structure of RAPP system
Figure 1 presents the general structure of the RAPP system, consisting of agents residing in the cloud and a robot.
The cloud part of the system contains a repository agent a_rep and a cloud agent a_cloud
The former holds the RApp store, enables the robots to download RAPP applications (RApps in short) delivered by the RApp providers and, additionally, may offer certain computational services.
The a_cloud represents one or more agents that might be activated by a_rep or are simply external service providers, such as external databases, email servers etc. -- because of this there is a striped background behind a_cloud.
Each robot contains a specific core agent a_core, which governs both its effectors and receptors, thus exposing the robot hardware through an appropriate representation to the RApps. The core agent a_core communicates with a_rep, thus it is able to download RApps.
RApps are composed of a single dynamic agent a_dyn executed on a robot and might be supplemented with agents running in the cloud.
When a_dyn is executed a_core becomes passive, whereas a_dyn supervises the robot using its predefined services offered by a_core.
Figure 1: General structure of RAPP system
When the computational capabilities of the robot are below requirements, the RAPP platform provides the extra computational power in the form of the necessary services. Simple services can be provided to the dynamic agent a_dyn and the core agent a_core by the repository agent a_rep directly or, if a composition of services is required to carry out the task, a cloud agent a_cloud is created. In the case when the cloud agent a_cloud is created the RAPP application is composed of two agents. The first one, as in the previous case, is formed as a dynamic agent a_dyn, which will perform its actions on the robot, and a second agent called the cloud agent a_cloud, which will provide the necessary computational services in the cloud. The dynamic agent dyn and the cloud agent a_cloud establish a communication link between themselves and from then on both preform the required RApp in conjunction. In this case a four agent structure appears.