CONTACT
Prof. S. Ducasse, stephane.ducasse AT inria.fr, INRIA, France
Prof. N. Bouraqadi, noury.bouraqadi AT mines-douai.fr, Mines Douai, France
Dr. M. Denker, marcus.denker AT inria.fr, INRIA, France
Dr. L. Fabresse, luc.fabresse AT mines-douai.fr, Mines Douai, France

CONTEXT
Building next generation systems that can not be stopped in deployment is an interesting challenge for industry.
Indeed, when we need to replace current software for an upgrade or a bug fix, it is mandatory to stop
the old running version, make the change and then restart the new version.
However, there are situations where a such process is either impossible or at least undesirable because
of the costs resulting from a shutdown (e.g production line, robot on mars, …).

We believe that software built with from the beginning the property to work indefinitely, will be by
construction more robust to change, intrinsically capable of evolution and more agile than traditional software.

Dynamic languages such as CLOS, Ruby, Python, Smalltalk and Pharo provide a support for updates that involve code change.
Even if they are more advanced compared to other languages, their solutions are mainly ad hoc and deserve being rethought.
We believe it is important to have a mechanism and an infrastructure that allow adaptive and safe software updates.

By “safe” we mean that this solution should support different conditions, such as a series of updates performed in the wrong sequence.
In such situations, instances of changed classes should migrate in a satisfactory fashion.
Safety also means verifying loaded changes. Changes should be checked and possibly rejected if they make the system
unstable or if they introduce errors.

SCIENTIFIC GOALS
The questions we would like to target in this PhD are the following:

- What is a good infrastructure to support reliable dynamic code update? Do we need to analyse changes?

- Is an infrastructure based on isolated environments enough to ensure update safety? What level of atomicity is required?

- What kind of meta-object protocol is required to migrate objets?

- Would it be interesting to have different versions of a given class or package active at the same time for the same software?

BIBLIOGRAPHY

. D. Duggan. Type-based hot swapping of running modules. In Intl. Conf. on Functional Programming, pages 62–73, 2001.
. M. Denker, T. Gîrba, A. Lienhard, O. Nierstrasz, L. Renggli, and P. Zumkehr. Encapsulating and exploiting change with Changeboxes. In Proc. Int. Conference on Dynamic Languages, pages 25–49. ACM Digital Lib., 2007.
. M. Dmitriev. Safe Class and Data Evolution in Large and Long-Lived Java Applications. PhD thesis, University of Glasgow, 2001.
. M. Hicks and S. Nettles. Dynamic software updating. ACM Transactions on Programming Languages and Systems, 27(6):1049–1096, nov 2005.
. J. Kephart. Research challenges of autonomic computing. In ICSE 2005, pages 15–22, may 2005.
. G. Kniesel. Type-safe delegation for run-time component adaptation. In R. Guerraoui, editor, Proceedings ECOOP ’99, volume 1628 of LNCS, pages 351–366, Lisbon, Portugal, June 1999. Springer-Verlag.
. I. Neamtiu, M. W. Hicks, G. Stoyle, and M. Oriol. Practical dynamic software updating for c. In PLDI, pages 72–83, 2006.
. G Polito, Stéphane Ducasse, N Bouraqadi, L Fabresse, M Mattone. Virtualization Support for Dynamic Core Library Update. Onward!, Oct 2015, Pittsburg, USA.
. X. Ren, F. Shah, F. Tip, B. Ryder, and O. Chesley. Chianti: A tool for change impact analysis of Java programs. In Proceedings of OOPSLA 2004), pages 432–448, 2004.

Our paper presented at the International Workshop on Smalltalk Technology 2015, Brescia Italy, as part of the PhD of LE Xuan Sang received the 1st prize, offered by the Lam Research Corporation.

A Meta Model Supporting Both Hardware and Smalltalk-based Execution of Fpga Circuits
High level synthesis (HLS) refers to an automated process that creates a digital hardware from an algorithmic description of some computation. From the perspective of Smalltalk, this process consists in converting a code from the OO level to the register transfer level (RTL), that supports direct compilation to the hardware level. In this paper, we present first steps to achieve this process. We introduce a Smalltalk-based meta-model that allows to express descriptions (i.e. models) of digital circuits. These descriptions materialize as Smalltalk code. A such circuit description can be run on top of the Smalltalk VM, simulating the parallelism intrinsic to hardware. Alternatively, it can be compiled into a binary representation directly transferable to FPGA chips, which can run and exchange data with Smalltalk objects.

We are glad to announce PharoJS, which is an infrastructure to run Pharo code on top of JavaScript. The goal of PharoJS is to allow developers benefit from the power of Pharo while targeting platforms that support JavaScript.

For example, PharoJS can be used to develop client side web applications. It can also be used to support cross-platform mobile apps based on Phone Gap.

PharoJS is freely available under MIT License. It can be dowloaded from SmalltalkHub.

This conference is aimed at addressing important aspects of robot control architectures, with a specific emphasis on distribution, verification and validation, languages and modeling, and implementation of control architectures. It brings together researchers and practitioners from universities, institutions and industries, working in this field. It intends to be a meeting to expose and discuss gathered expertise, identified rends and issues, as well as new scientific results and applications around software control architectures related topics, through plenary invited papers.

Theme
Due to their increasing complexity, nowadays intervention robots, that to say those dedicated for instance to exploration, security or defence applications, definitely raise huge scientific and commercial issues. Whatever the considered environment, terrestrial, aerial, marine or even spatial, this complexity mainly derives from the integration of multiple functionalities: advanced perception, planning, navigation, autonomous behaviours, in parallel with communication or robots coordination enable to tackle more and more difficult missions.

But robots can only be equipped with such functions if an appropriate hardware and software structure is embedded: the software architectures will hence be the main concern of this conference.
As quoted above, the control architecture is thus a necessary element for the integration of a multitude of works; it also permits to cope with technological advances that continually offer new devices for communication, localization, computing, etc. As a matter of fact, it should be modular, reusable, scalable and even readable (ability to analyze and understand it).
Besides, such properties ease the sharing of competencies among the robotics community, but also with computer scientists and automatics specialists as the domain is inherently a multidisciplinary one.

Numerous solutions have been proposed, based on the “classical” three layers architecture or on more “modern” approaches such as object or component oriented programming. Actually, almost every robot integrates its own architecture; the workshop will thus be a real opportunity to share reflections on these solutions but also on related needs, especially on middleware for robotics, which are of particular importance in multi-robot applications for instance.
Hence, this conference on control architectures of robots aims at gathering a large number of robotics actors (researchers, manufacturers as well as state institutions) in order to highlight the multiple issues, key difficulties and potential sources of advances.

Schedule – Dates
- Paper submission (full paper or extended abstract): May 18 2015
- Paper Acceptation Notification : May 29 2015
- Camera Ready due : June 29 2015
- Conference: 29-30 June 2015

Submission Guideline
- Even if CAR is a french conference, we prefer articles written in english
- No specific style is asked : latex article style is OK
- No limit on article length, usually articles for CAR are between 6 and 17 pages long !

Web Page
http://car-conference.fr/

Scientific Committee
- David Andreu LIRMM, Univ. Montpellier 2
- Noury Bouraqadi Ecoles des Mines de Douai,
- Jacques Malenfant LIP6, UPMC
- Roger Pissard-Gibollet INRIA Grenoble,
- Julien Ponge CITI-INRIA, INSA de Lyon
- Olivier Simonin CITI-INRIA, INSA de Lyon
- Serge Stinckwich UBCN & UMMISCO, IRD/UPMC

Recently, we released several ROS packages for multi-robot exploration, including:

  1. explore_multirobot http://wiki.ros.org/explore_multirobot: is a multi-robot version of the explore package.
  2. map_merging http://wiki.ros.org/map_merging: merges multiple maps with knowledge of the initial relative positions of robots.
  3. tf_splitter http://wiki.ros.org/tf_splitter: decomposes the /tf topic into multiple ones.
  4. pose_publisher http://wiki.ros.org/pose_publisher: provides current position and orientation of the robot in the map.

These packages have been tested in ROS Groovy. However, Groovy is EOLed and there are no documentation or release jobs running anymore. We will test in more recent versions in order to improve our wiki.