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Embedded targets normally do not have much resources to aid developing and debugging the software. So model-driven development (MDD) is used for designing embedded software with a `first time right' approach. For such an approach, a good way of working (WoW) is required for embedded software development using MDD techniques. This paper discusses the preferred way of working for the development of embedded control software. Control software requires hard real-time support for the loop controllers. These controllers directly control the motor output. Soft and non real-time levels can be used for non loop control related software tasks. The paper also discusses model structure optimisation techniques, which prevent the complexity of resource scheduling for large robotic setups, These techniques allow the designer to keep his own preferred point of view, as the techniques try to optimise the model into efficient software from a execution point of view. This saves a huge amount of design effort, especially for distributed targets.

In this paper we show that using co-simulation for robot software design will be more efficient than without co-simulation. We will show an example of the plotter how the co-simulation is helping with the design process. We believe that a collaborative methodology based on model-driven design will improve the chances of closing the design loop early, improving cross-discipline design dialog, and reduce errors, saving cost and time.

This paper is about using templates and passing model-specific information between tools via parameterized tokens in the generated, high-level code, to get a better separation of design steps. This allows for better quality of the models and more reuse, thus enhancing the efficiency of model-driven design for the (industrial) end user. This is illustrated by the realization of the embedded software of a real system. We conclude that reuse is easier. However, the presented method can be generalized more, as to connect to other tools and platforms.

This paper describes and compares five CSP based and two CSP related process-oriented motion control system implementations that are made for our Production Cell demonstration setup. Five implementations are software-based and two are FPGA hardware-based. All implementations were originally made with different purposes and investigating different areas of the design space for embedded control software resulting in an interesting comparison between approaches, tools and software and hardware implementations. Common for all implementations is the usage of a model-driven design method, a communicating process structure, the combination of discrete event and continuous time and that real-time behaviour is essential. This paper shows that many small decisions made during the design of all these embedded control software implementations influence our route through the design space for the same setup, resulting in seven different solutions with different key properties. None of the implementations is perfect, but they give us valuable information for future improvements of our design methods and tools.

Embedded software design for mechatronic systems is becoming an increasingly time-consuming and error-prone task. In order to cope with the heterogeneity and complexity, a systematic model-driven design approach is needed, where several parts of the system can be designed concurrently. There is however a trade-off between concurrency efficiency and integration efficiency. In this paper, we present a case study on the development of the embedded control software for a real-world mechatronic system in order to evaluate how we can integrate concurrent and largely independent designed embedded system software parts in an efficient way. The case study was executed using our embedded control system design methodology which employs a concurrent systematic model-based design approach that ensures a concurrent design process, while it still allows a fast integration phase by using automatic code synthesis. The result was a predictable concurrently designed embedded software realization with a short integration time.

This paper presents two algorithms for analysing gCSP models in order to improve their execution performance. Designers tend to create many small separate processes for each task, which results in many (resource intensive) context switches. The research challenge is to convert the model created from a design point of view to models which have better performance during execution, without limiting the designers in their ways of working. The first algorithm analyses the model during run-time execution in order to find static sequential execution traces that allow for optimisation. The second algorithm analyses the gCSP model for multi-core execution. It tries to find a resource-efficient placement on the available cores for the given target systems. Both algorithms are implemented in two tools and are tested. We conclude that both algorithms complement each other and the analysis results are suitable to create optimised models.

Most motion control systems for mechatronic systems are implemented on digital computers. In this paper we present an FPGA based solution implemented on a low cost Xilinx Spartan III FPGA. A Production Cell setup with multiple parallel operating units is chosen as a test case. The embedded control software for this system is designed in gCSP using a reusable layered CSP based software structure. gCSP is extended with automatic Handel-C code generation for configuring the FPGA. Many motion control systems use floating point calculations for the loop controllers. Low cost general purpose FPGAs do not implement hardware-based floating point units. The loop controllers for this system are converted from floating point to integer based calculations using a stepwise refinement approach. The result is a complete FPGA based motion control system with better performance figures than previous CPU based implementations.

To improve feedback on how concurrent CSP-based programs run, the graphical CSP design tool has been extended with animation facilities. The state of processes, constructs, and channel ends are indicated with colours both in the gCSP diagrams and in the composition tree (hierarchical tree showing the structure of the total program). Furthermore, the contents of the channels are also shown. In the Fringe session, we will present and demonstrate this prototype animation facility, being the result of the MSc project of Hans van der Steen, and ask for feedback.

The software design is one of the most challenging tasks during the design of a mechatronic system. On one hand, it has to provide solutions to deal with concurrency and timeliness issues of the system. On the other hand, it has to glue different disciplines (such as software, control and mechanical) of the system as a whole. In this paper, we propose a model-driven approach to design the software part of a mechatronic system, which consists of two major parts: systematic modeling and correctness-preserving synthesis. The modeling stage is divided into four steps, which focus on different aspects (such as concurrency, multiple disciplines and timeliness) of the system respectively. In particular, we propose a set of handshake patterns to capture the concurrent aspect of the system. These patterns assist designers to build up an adequate top-level model efficiently. Furthermore, they separate the system into a set of concurrent components, each of which can be further refined independently. Subsequently, the multidisciplinary and realtime aspects of the system are naturally specified and analyzed in a series of refinements. After the important aspects of the system are specified and analyzed in a unified model, a software implementation is automatically synthesized from the model, the correctness of which is ensured by construction. The effectiveness of the proposed approach is illustrated by a complex production cell system.

The work presented here is on setting up methodological support, including (prototype) tools, for the design of distributed hard real-time embedded control software for mechatronic products. The use of parallel hardware (CPUs, FPGAs) and parallel software is investigated, to exploit the inherent parallel nature of embedded systems and their control. Two core models of computation are used to describe the behavior of the total mechatronic system (plant, control, software and I/O): discrete event system (DES) and continuous time system (CTS). Thesemodels of computation are coupled via co-simulation, to be able to do consistency checking at the boundaries. This allows for integration of discipline-specific parts on the model level (during design phases) instead of on the code level (during realization and test phases). Crossview design-change influences get specific attention, to allow for relaxation of the tension between several dependability issues (like reliability and robustness), while keeping design time (and thus design costs) under control. Furthermore, the design work can be done as a stepwise refinement process. This yields a shorter design time, and a better quality product. The method is illustrated with a case using the tools being prototyped.

The design of embedded control systems for monitoring and control of mechatronic systems has a multidisciplinary development trajectory. These systems consist of heterogeneous components developed by different disciplines (control engineering, electrical engineering, software engineering and often many more). The design trajectory needs therefore a multi-disciplinary design methodology that enables concurrent design and interactions between all involved disciplines, reducing inconsistencies and conflicts that occur during the design phase. This paper proposes a multi-view methodology to address the above-mentioned issues. The main purpose is to shorten the design time and at the same time increasing the reliability and predictability of embedded (computer) control systems.

gCSP is a graphical tool for creating and editing CSP diagrams. gCSP is used in our labs to generate the embedded software framework for our control systems. As a further extension to our gCSP tool, an occam code generator has been constructed. Generating occam from CSP diagrams gives opportunities to use the Raw-Metal occam eXperiment (RMoX) as a minimal operating system on the embedded control PCs in our mechatronics laboratory. In addition, all processors supported by KRoC can be reached from our graphical CSP tool. The commstime benchmark is used to show the trajectory for gCSP code generation for the RMoX operating system. The result is a simple means for using RMoX in our laboratory for our control systems. We want to use RMoX for future research on distributed control and for performance comparisons between a minimal operating system and our CTC++/RT-linux systems.

This paper describes a method using Hardware-in-the-Loop Simulation as a means for multidisciplinary design support. The method presented here, aims at supporting the design of heterogeneous embedded control systems. The method considers the implementation process as a stepwise refinement from physical system models and control laws to efficient control computer code, and that all phases are verified by simulation. Since many systems are distributed in nature we use a link driver library based on the CSP channel concept to support this. Communication peculiarities are encapsulated by these link drivers. Experiments with a basic mechatronic set up show that the HIL Simulated system behaves as the real system and can be successfully incorporated.

From version 3.2, 20-Sim will contain a new tool, called C-code generation. With this tool it will be possible to generate C code from a 20-Sim model. This tool works on basis of templates. For each target, a target specific template has to be made. The goal of this project was to write a new 20-Sim template for a PC/104 target, a embedded Intel 80486 pc on the mobile robot Arty. It should to be possible to control the robot with a 20-Sim model. The template had to be written using the Phar Lap TNT Toolsuite Lite, a toolsuite for real-time embedded development. The written template is working and to demonstrate this, a 20-Sim model that controls the robot is made. Another goal of this project was testing the code generation tool and doing some recommendations for improvement. From this project it followed that this tool works good, but that the following points have to be improved: · Controlling the target hardware from a 20-Sim model is possible but only via a time-consuming workaround route. · The generated code is large, because it contains many not-used functions and redundant variables and equations. · The Runge Kutta routines fail to work in the existing templates when a model has no states.