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Discussion and Conclusions

This paper addresses an open issue in autonomous soft- ware for robotics platforms: how to perform intensive ex- periments according to some structured methodology. We have first produced the OGATE framework to support au- tomated testbench campaigns to achieve performance mea- sures of different autonomous controllers. This framework is composed of (i) a methodology to define and guide the testing process, and (ii) an engineering tool to support such a methodology. The paper in particular introduces a method-

ology for evaluating deliberative robotic components and a way for compact visualising the result of its application. Us- ing the new framework we have analyzed different planning policies for the deliberative component of the GOACsystem here considered as an external system. Assessment has in- volved inspecting internal measures of the deliberative com- ponent while executing scenarios with increasing complex- ity. Within these tests we have been able to obtain differ- ent reports describing the performance of the system that al- lows us to obtain conclusions that were hard to be achieved performing standalone tests. In particular for the extensive GOACtesting we have been able to identify an issue in the single goalpolicy of the planning component, and we have been able to conclude that the all goals policy is open to dynamic controllability issues.

Some specific issues still require some additional com- ments. First, the need of considering also stochastic model- ing and, more in general, to allow for setting up more com- prehensive and complex testing scenarios is a further de- sired feature. As for assessment of plan-based components, OGATE is a rather new solution and then the present pa- per is more focused on proposing an evaluation methodol- ogy and a technological supporting tool. Indeed, as a start- ing point we are considering a set of preordered scenarios from a real world robotic application (hence emphasizing the realism of the use case). Nevertheless, OGATE can be seamlessly extended in order to consider more complex sce- narios, e.g., including stochastic features and to allow users performing more thorough test campaigns analysis. This is actually an ongoing work.

Then, the choice of relying on plugins enables OGATE to connect to any kind of control architecture notwithstanding which kind of robotic platform/software is deployed. Thus, OGATE aims to be as much as possible platform/software independent. Nevertheless, the implementation of a ROS plugin is in our agenda for future versions of the framework. In order to develop a plugin to connect OGATE to an autonomous controller, some technical work by skilled engineers and/or control architecture experts is obvi- ously required. Nevertheless, after such mandatory step, OGATE is requiring system users (i.e., not necessarily ex- perts/engineers) to generate two XML files for describing i) the set of components necessary to actually execute the au- tonomous controller and ii) the metrics to be measured as well as the data required to generate the evaluation reports. Both files can be generated through the graphical environ- ment of OGATE2. The file contains detailed information

(order of execution, paths, processes, parameters, simulator settings file, etc.) about software processes to be issued in order to properly activate the GOAC and the simulator soft- ware.

Finally, among future developments, a further analysis of robot missions evaluation is required to leverage OGATE tool in order to identify relevant metrics to evaluate control architectures also allowing metrics customization according

2

As an example, at the following link, an example of an XML file with the information to execute the GOAC controller is pro- vided: https://www.dropbox.com/l/UBKryBFRaZq7taCzdUFCso.

to specific robot mission requirements. In general, the defi- nition of a more thorough set of standard metrics is highly desirable and would constitute a not trivial and important contribution in this field. Moreover, the use of OGATE will be considered for comparing different plan-based delibera- tive platforms on the same benchmark tests.

Acknowledgments

Pablo Mu˜noz is supported by the European Space Agency (ESA) under the Networking and Partnering Initiative. UAH authors are partially supported by the Junta de Comunidades de Castilla-La Mancha project PEII-2014-015-A. CNR au- thors are partially supported by the Italian Ministry for Uni- versity and Research (MIUR) and CNR under the GECKO Project (Progetto Bandiera “La Fabbrica del Futuro”). Au- thors want to thank to the ESA’s technical officer Mr. Michel Van Winnendael for his continuous support.

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