An interdisciplinary approach to the functional development of mechatronic systems
Automotive products carry large numbers of mechatronic components – components where mechanical processes are controlled by software embedded in electronic systems. Increasingly complex electronic products – like drive by wire systems – call for the use of a broad range of simulation tools that can verify product characteristics early on in the development cycle. Specific domains – like mechanics, electronics and software – each use a wide variety of their own special simulators. Yet for the timely simulation of mechatronic components, these three domains first need to be linked together, and it is this connectivity which enables further reductions in development times and costs despite ever more stringent requirements in terms of functionality and quality.
As a more intensive use of software in innovations in functionality and product development has positive cost effects on production, an increasingly large variety of computer assisted development and simulation tools are being used in product development to test whether the product meets preset requirements early on in the development cycle. Yet these tools each cover only one part of the mechatronic domain, and thus can only show certain aspects of the behavior of the finished product. There is often no way of consistently describing and checking interactions between the individual domains which means that risks, tolerances and malfunctions first come to light in a prototype of the mechatronic components. Virtual integration of the three domains can offer precise assessment and validation of such interactions and the overall interplay of the mechatronic components.
Over the past few years the Digital Mock-Up (DMU) concept has established itself in industrial practice as a means of integrating virtual (part)products. However today’s DMU is still mainly confined to the geometric integration and analysis of various partmodels, and still lacks ways of integrating the behavior and interworking of electronic, mechatronic and software sub-components that can open them up to cross-domain analysis and debugging. Industry is still urgently seeking software tools and methods for the functional integration of virtual mechatronic products.
The main thrust of the FunctionalDMU solution lies in the way it extends 3D-construction prototyping (DMU) to cover behavior models which can exist in various modeling languages for a variety of simulators. On the technical level coupling of these types of disparate behavior models and their simulators calls for a framework that can run types of behavior models on the right simulators - such as SimPack®, Dymola®, MATLAB/Simulink®, AdvanceMS® or Rhapsody® - and coordinate, synchronize and display simulator data exchange. The key framework component is a communication infrastructure or simulation bus which enables interchange of consistent results between all component s and synchronization of all connected simulators. This simulation bus is domain-neutral and realizes the exchange of simulation data and interaction and control commands. Wrappers are used for simulators to enable specific simulator data to be given overall consistency and uniformity. The FDMU Framework is also enriched with other components and services for visualization, compilation, administration, data management and capture of simulation results.
- Develops an open software platform for the integration and simulation of behavior models from the domains of mechatronics, electronics and software.
- Develops an interactive visualization environment (patterned on DMU) for the integrative presentation of simulation results from various disciplines together with their interactions and effects.
- Develops a methodology for the planned structural deployment of FDMU in industrial enterprises.
- Offers a functional and easily manageable Design Review of complex mechatronics.
- Early recognition of problems in the interaction of mechatronic components means shorter development cycles.
- Evaluation of (parameter) studies on the interworkings of mechatronic components means a better quality of product in all domains.
- Functionality across all domain boundaries can be experienced and communicated in the early stages of the development cycle.
- Functional prototypes enable cross-departmental analysis
- Early multi-disciplinary integration support for mechantronic systems.
- Proof of concept for planned inspection units and specifications in the run-up to real life inspection.
Drive-by-wire systems enable active intervention in the driving and steering of cars with sensors, electromechanical actuators for power transmission and software-controlled human-machine interfaces. In terms of the development and testing of such modern driver assistance systems, and to show how passive components can be replaced by proactive systems, the case of the Lane Departure Warning (LDW) system has been selected to show how such systems can be built in a virtual world using a cooperative integration and testing framework, and tested in an early stage of the development cycle. The demonstrator uses a range of simulators (PCs) for distributed computing that simulate vehicle behavior – a driving simulator for generating highly realistic driving data, Telelogic Rhapsody® for simulation of automotive software in controlling devices, MATLAB/Simulink® for computing and simulating various behavioral models, and an interactive visualization of the driver cockpit. Technical coupling of these behavioral models with their simulators and software enables model-based identification and evaluation of the lane position and behavior of the vehicle. If the car threatens to drift out of the lane, the LDW automotive software flashes a warning sign in the driver cockpit.