GEMS - Generic EMBOCON Minimal Supervisor - 2013

GEMS Specification

The GEMS - Generic EMBOCON Minimal Supervisor is designed to be a minimal-footprint implementation of the supervisor specication. The GEMS was implemented in the EMBOCON project o�ering the full support of the entire set of standard interfaces of the EMBOCON platform as well as measuring function call computation times and logging of all data.

Te architecture of GEMS includes the four supported interfaces and the data which is exchanged. The GEMS implementation supports all standard function call denitions of the interfaces and some of the optinonal function call denitions.

The implementation language of GEMS is a combination of C and C++. The interfaces are linked via shared libaries under the Linux operating system. The source code is released as open-source at the end of the project under the MIT license using the GitHub repository system. The respository location of GEMS is the following: https://github.com/EMBOCONcs/GEMS.git. GEMS is contained in single projects for the Eclipse IDE.

The GEMS is used together with the state-of-the-art numerical algorithms developed within the project to show the applicability and exibility of the software platform as well as the performance of the optimization packages on selected applications across di�erent target sectors.

Supervisor Specification

The supervisor of the online part of the EMBOCON software platform forms the communication manager between an optimizer, an observer and an application or simulation environment of the optimization routine. The supervisor is responsible for the initialization and freeing of the di�erent elements and for triggering the functions calls of elements in the right order. The supervisor o�ers logging of data like controls, states etc. and measures computation times for all function calls. The measured timings together with the logged data can be used for testing, validation and performance evaluation of numerical algorithms.

The standard computation cycle of the supervisor starts with the setup of the elements of the online part by connecting them to the supervisor. Next, the creation and initialization phase starts by initializing the application or simulation environment and getting the rst measurements of the current state and the parameters of the system. These measurements are used to trigger the creation and initialization step of the observer and of the optimizer including the creation and initialization of the connected models. In the initialization, rst control inputs and states measurements are read from the models. After the initialization of all elements is done, the optimization cycle is executed for a predened number of steps by rst calling the makeObsStep function of the Observer Interface using the inital controls and state measurements. The resulting states of the makeObsStep call are passed to the optimizer and the makeOptStep function is called. The optimizer calculates new control inputs for the next step. The resulting control inputs of the optimizer call are passed to the simulation or application by calling the makeSimStep function of the SimulationApplication Interface. Then new measurements of the system response to the applied control actions are passed again to the observer and the makeObsStep function of the Observer Interface is called to calculate the next states. This cycle is repeated until a predened number of steps as a termination criterion is reached. During the optimization cycle computation times for any function calls are measured and logged with all data exchanged via the supervisor.

The supervisor is not required to read and interpret conguration les for numerical algorithms connected to it. If conguration les turn out to be necessary for connecting a numerical algorithm or an element of a numerical algorithm to the supervisor, the numerical algorithm implementation has to take care of the conguration le handling.

The format of the log les of the EMBOCON supervisor is not restricted to a specic format. An implementation is only required to log all exchanged data and time measurements of all function calls. Other features of the supervisor like graphical user interfaces, functionalities for plotting and visualization of results, comparison of results, providing a result and a model database including import and export functions are optional features of single realization of a supervisor, but are not mandatory for a valid supervisor implementation.