Official Project Kick-off for DSE 2.0

Today was the official project kick-off for the research project “Design Space Exploration 2.0: Towards Optimal Design of Complex, Distributed Cyber Physical Systems”. This project is a part of the Partnership Program Mastering Complexity (MasCot), funded by NWO Domain Applied and Engineering Sciences (AES) together with ESI (TNO). The University of Amsterdam and Leiden University are the academic partners, spearheaded by Andy Pimentel and Todor Stefanov. The carrying industrial partner is ASML, but with Philips, Siemens and ESI as parts of the user committee.

The main goal of the project is to extend existing methods for design-space exploration, often developed for on-chip systems, to cover complex distributed cyber-physical systems (dCPS), such as the lithography machines made by ASML. Designers of such systems need quick answers to so-called “what-if” questions with respect to possible design decisions/choices and their consequences on non-functional properties, such as system performance and cost. This calls for efficient and scalable system level design space exploration (DSE) methods that integrate appropriate application workload and system architectures models, simulation and optimization techniques, as well as supporting tools to facilitate the exploration of a wide range of design decisions. However, such DSE technology for complex dCPS does currently not exist. This projects hence tries to answer the question of how perform efficient and effective DSE for complex, distributed cyber-physical systems.

In today’s kick-off meeting, all stakeholders in the project had an opportunity to introduce themselves and refamiliarize themselves with the project and its goals. The two PhD students who will be working on the project, Marius and Faezeh, from UvA and Leiden, respectively, also gave a brief overview of the work they had done in the first three months of the project, which included a literature review and generation of high-level simulation models for different parameter settings.

I am directly involved in this project through my part-time appointment at UvA. As Marius’ second promotor, I will help him on his journey towards a PhD. I also have an interest in this project as an ESI Research Fellow and part of the MasCot Core Team. In this capacity, I am happy to help linking this project to ESI’s applied research projects, in particular at ASML, to exploit possible synergies, and to stimulate exchanges with other projects in the MasCot program.

Thales and University of Amsterdam Strengthen the ESI Ecosystem

ESI has just made a press release to announce that both Thales and the University of Amsterdam (UvA) has joined as partners in its open-innovation ecosystem. ESI’s ecosystem, based on open innovation, plays an important role in maintaining the leading competitive position of the Dutch high-tech industry. Together with universities and partner companies, ESI develops methodologies and tooling that are in line with the vision and needs of the high-tech industry, making use of the latest insights from universities. In an industry-as-a-lab setting, system engineering methodologies are developed, tested and validated on site at and with partners.

With the addition of UvA and Thales, ESI’s ecosystem now has more industrial and academic partners than ever before, which shows great promise in difficult times. Personally, I am very happy to see that the university where I work decided to further invest in its collaboration with ESI and join the partner board. Similarly, Thales is the company I have worked with in applied research projects for the past five years, and it pleases me that they see the benefits of this collaboration.

Read the full press release from ESI here.

Update:
The press release was picked up by a number of different media outlets, e.g.

UvA – UvA Informatics Institute and Thales strengthen ESI open-innovation ecosystem

Bits & Chips – Thales and UvA (re)join ESI

Emerce – Thales en het Informatica Instituut van de Universiteit van Amsterdam versterken ESI (TNO) open-innovatie ecosysteem

Link Magazine -Thales en de Universiteit van Amsterdam versterken het open-innovatie systeem van ESI TNO 

Engineers Online – Thales en UvA versterken Esi open-innovatie ecosysteem voor hightech

Embedded Software and Systems Course @ UvA Continues to Evolve

The fall semester of the very special academic year 2020/2021 is over. Most of the students following the Master of Software Engineering program at the University of Amsterdam have just completed my course Embedded Software and Systems (ESS). The ESS course had changed in a three important ways this year.

Firstly, a generic lecture about Petri Nets was changed to a series about two lectures, explaining how Petri Nets can be used to model and analyze software interfaces and components. Part of the material for this course was reused from the course Modelling and Analysis of Component-based Systems (MOANA-CBS), developed together with Thales targeting an industrial audience. These new lectures also prime students nicely for a lecture about the DYNAMICS project, a research collaboration between ESI and Thales. This allows me to show how these models and analyses can be used in practice to address problems related to software evolution by detecting incompatibilities and generating adapters when updating software interfaces. A generic lecture about the data-flow model of computation was removed to create room for this new material, but I am happy to teach fewer modelling formalisms and have more time to go in depth and show how they can be used to solve industrial problems. A nice result of this change to the course is that three master students have accepted thesis projects in the area of modelling and analysis of software components and interfaces in collaboration with ESI under the supervision of myself and my colleague Debjyoti Bera.

Secondly, the course project was redeveloped this year. Previously, students used Mathworks Stateflow to program Lego Mindstorm EV3 rovers to follow a line, avoid obstacles, and count objects. However, this project felt a bit too much like a toy and there were technical problems with both rovers and tools that were hard to overcome and limited the education experience. In particular, it was not easily possible to see or influence how code was generated for the Lego Mindstorm robots, which felt like a missed opportunity when teaching model-based engineering. 

Two bachelor students did their theses in spring to evaluate the suitability of using the TurtleBot3 Burger robot, both in reality and in simulation using Gazebo, in the course. In addition, Stateflow was exchanged for Yakindu Statechart Tools, which is easier to use and gives us the flexibility we need in code generation. The new application developed in the project is to use Yakindu to program the TurtleBot to autonomously drive through a maze and map it.

Lastly, the COVID-19 pandemic required the entire course to be taught online. As a result, used a blended learning approach and prerecorded the lectures so that the students could watch them when they wanted to. Online interactive sessions were added to the course where the students could ask questions about the lectures, and participate in quizzes and group discussions. Online teaching meant that the students did not have access to the four physical TurtleBots that we had purchased. Luckily, the newly developed course project could be done with simulations in Gazebo. Below is a demo from one of the groups that very successfully solved the assignment. 

The ESS course is continuously evolving and maturing and next year will be no different. Most importantly, we hope that the pandemic will be over by then and that we can put our three physical TurtleBots to good use.

Model-based Engineering Dominates Software-Centric Systems Conference

I attended the online edition of Software-Centric Systems Conference (SC2) today. Although I prefer the networking and social aspects of a physical conference, it was nice to enjoy these presentations from the comfort of my couch.

It was interesting to see that most of the conference presentations were related to domain-specific languages (DSLs) in one way or another. There were also presentations about model-based testing and digital twinning. I am not sure if model-based engineering was an intentional theme, or if this is just what is considered interesting in software-centric systems in the Netherlands for the moment. However, this suggests that the applied research into model-based design methodologies done by ESI (TNO) together with its industrial eco-system is highly relevant.

A highlight for myself was the two presentations about the Component Modelling and Analysis (ComMA) DSL. This is not only because it relates to my research on evolvable interfaces, but also because of the main message that the industry can achieve a lot through open innovation in areas that are not their core business, such as specification, verification, and evolution of software interfaces. Great news that ComMA will become open-source in 2021!

DYNAMICS Project in Keynote at Software-Centric Systems Conference

Two months ago, I mentioned that Bits & Chips had published an article about the ComMA (Component Modelling and Analysis) language and how it is being used in Philips and Thales to address challenges related to integration and evolution. The latter part, about semi-automatic detection and correction of interface incompatibilities as interfaces evolve is the topic of the DYNAMICS project, a research project between ESI (TNO) and Thales. This joint story, where two companies from different domains together presented their challenges and how it was addressed by technology developed by ESI was much appreciated by Bits & Chips and was invited as a keynote at the Software-Centric Systems Conference (SC2), which takes place on Thursday November 5. If you are interested in hearing this keynote, please register for the event. All presentations are also available on-demand after the event in case you cannot attend in real time.

Design Methodologies for Cyber-physical Systems

In this short two minute presentation, I introduce myself and my fundamental and academic research into design methodologies for cyber-physical systems. I sketch a high-level view of the problem and outline a direction based on model-based engineering in which my previous work into domain-specific languages and analysis non-functional behavior fits. For a more elaborate description of my research, please have a look at my research page.

Course on Modelling and Analysis of Component-based Systems

A course called “Modelling and Analysis of Component-based Systems” (MOANA-CBS) is being developed in collaboration with Thales as a part of the DYNAMICS project. The course addresses the challenge of overseeing the explosion of possible interactions between asynchronously communicating components in component-based systems. Some of these interactions may be undesirable and leave systems prone to deadlock, livelock, race conditions, and buffer overflows, reducing software quality. The course participants in the course learn how to mitigate this problem by modelling the behavior of components and interfaces using Petri Nets, a well-known formalism suitable for describing asynchronously communicating systems. Theory is linked to practice through demonstrations of relevant examples using the ComMA tool. Using properties and analysis methods for Petri Nets, they learn how to identify patterns in component and interface design that may cause the aforementioned problems, as well as design guidelines for how to avoid them. The course is taught using a combination of lectures, assignments, demonstrations, discussions, and reflection.

We piloted parts of the course at Van der Valk Hotel in Arnhem on October 7 and 8, attended by 12 software architects from Thales and Luminis. The course was positioned as a part of their Accelerate program, which aims to accelerate young architects from the two companies into a more senior role. We felt that the delivery of the course went well and evaluations from the participants suggests it was well-received. The evaluation of this pilot also highlighted some further points for improvement that will be considered going forward.

Component Modelling and Analysis (ComMA) in Bits & Chips

Bits & Chips just published an article about ComMA (Component Modelling and Analysis). ComMA addresses key design and verification challenges for complex systems comprising many components developed by different parties, challenges that are frequently encountered in the high-tech industry across application domains. The challenges are tackled by allowing structure and behavior of component interfaces to be formally specified using a set of domain-specific languages. From this specification, a number of artifacts are automatically generated, including system tests, run-time monitors that detect protocol violations, performance metrics, and documentation. Together, these artifacts reduce the time to design, integrate, and evolve complex high-tech systems, allowing the next generation of these systems to be developed faster and with higher quality.

ComMA was developed by ESI (TNO) in applied research projects with Philips. Successfully proving the approach in an industrial context at Philips has sparked interest from other companies, including Thermo Fisher Scientific, Thales, and Kulicke & Soffa. This eco-system of high-tech companies is expected to increase further as the ComMA tooling becomes open source as part of the Eclipse Foundation.

The article also mentions the applied research project DYNAMICS, for which I am the technical lead. Here, ESI and Thales have been looking at challenges and opportunities related to the evolution of interfaces. The strong point of interfaces is that they abstract from the component providing a particular functionality, allowing it to be changed or even replaced without compromising the overall functionality of the system. However, eventually the interfaces themselves need to be updated to prevent technical debt, and at that point all components relying on that interface are affected simultaneously. In the DYNAMICS project, we study how to automatically detect whether a change to the protocol of an interface is backwards compatible and if this is not the case, semi-automatically generate adapters that bridge the differences with previous versions. The benefit of this approach is that it reduces the time and cost of interface updates, allowing them to evolve faster and avoid creative workarounds that ultimately lead to unreliable systems and lower software quality. If you are interested in reading more about this work and how it leverages ComMA and Petri Net technology to achieve this, read this overview paper from last year.

Comma interfaces open the door to reliable high-tech systems

Bachelor Thesis on Synthetic Interface Generation Defended

Mohammed (Mo) Diallo just defended his bachelor thesis entitled “Towards the Scalability of Detecting and Correcting Incompatible Service Interfaces“. This work is carried out in the context of a project between ESI (TNO) and Thales that developed a five-step methodology for automatic detection and correction of behavioral incompatibilities resulting from evolving software interfaces (see paper for more details). Mo’s thesis provides a starting point for evaluating the scalability of the proposed methodology. An essential ingredient towards this is the ability to synthetically generate interfaces of various complexity. The thesis has two main contributions: 1) a notion of interface complexity in terms of inputs, outputs and non-determinism is defined and the relation between these parameters is studied, and 2) the methodology for a ComMA interface generator using user-supplied complexity parameters, and its implementation in a supporting tool, is introduced.

I would like to thank Mo for the excellent work he delivered in this thesis, and I am happy that he will continue working over summer to extend it.

Four Projects Granted to Fight the Complexity of Cyber-Physical Systems

During the past two years, I have been involved with setting up the Partnership Program Mastering Complexity (MasCot), funded NWO Domain Applied and Engineering Sciences together with ESI (TNO). After a long process of defining the key topics, writing the call, and aligning with applicants, four innovative research projects have finally been granted, allocating three million euros to research on software restructuring, testing, scheduling and design of cyber-physical systems. Congratulations to Andy Pimentel, Twan Basten, Jan Tretmans, Eelco Visser, and their collaborators for the accepted projects. I am looking forward to seeing the results!

The full story is available on the ESI website.