ODESIM : Project overview
Current MBS simulation programs have powerful analysis capabilities that allow them to simulate complex systems with rigid and flexible bodies subject to different kinds of external forces, control laws, nonlinear effects, etc. Most of these programs assume that the dimensions of the machine are perfectly known and that the user is only interested in predicting its behaviour over time. However, this is not the case during the design phase, in which the designer starts from a draft design and has to refine its dimensions in successive iterations. With current MBS analysis programs, the designer must perform kinematic and/or dynamic analysis in each design step, assess the performance of the system, and accordingly, take a decision on what dimensions should be modified to improve the performace. This iterative process has two main drawbacks: first, it relies heavily on previous experience with similar designs and therefore can only be done by experts, and second, it is very time consuming since the designer has to repeat the assessment of performance, the decision making and the dimensional modification in every iteration step.
In ODESIM, the multibody design problem is addressed from the beginning of the design process, which starts with the CAD definition of parts. In the CAD program, the designer creates a parametric or variational model of each part. From this parametric or variational model, the designer can make fast modifications of the geometry based on only a few dimensions that are taken as design variables. ODESIM will create a multibody model from the parametric definition of parts, that will later be optimized according to some objective function and design constraints.
MBS design and, in particular, dynamic optimization of mechanisms, is a very time consuming task that can only be addressed with High Performance Computing and Networking (HPCN) techniques for moderate to large size problems. ODESIM will make use of parallel computing in environments with shared-memory multiprocessor computers and/or clusters of heterogenous workstations.
The main objectives of ODESIM can be summarized in the following points:
- To develop software modules for the kinematic synthesis and dynamic design of MBS using HPCN, linked to a parametric and variational interactive CAD modeller.
- An interactive interface for the definition of design variables, geometry, objective function, etc., that will also permit the user to monitor the progress of the optimization process as well as to stop, modify and restart it at any time.
- To implement and run the most time-consuming tasks in a HPCN environment making use of parallel processing in multi-CPU computers and clusters of workstations.
The starting point for this project will be the CAD and MBS simulation packages currently available within the consortium. They will be enhanced with additional capabilities that will allow the new modules developed in this project to run in the same environment.
The use of standards like UNIX, C++, X-Windows, Motif and STEP and a modular structure based on Object Oriented Programming techniques, will guarantee the openness, portability and scaleability of the system.
The consortium provides an adequate mix of industries and research centers of proved excellence. There is a strong commitment within the consortium to exploit the results in a number of industrial applications including automotive engineering, aerospace, robotics and machinery design. There are also plans to market the software results of the project.
