Abstract
Important publications reveal a growing interest in analysis methods for multibody systems that may facilitate the self-formulating algorithms, having as main goal the reducing of the processing time in order to make possible real time simulation. These methods were used to develop powerful modeling and simulation programs that allow building and simulating any mechanical system in a fraction of the cost of traditional hardware prototyping. Virtual prototyping has become very important in the automotive industry, such as body hardware engineering, including the design and simulation of the windshield wipers. In this paper, we attempt to develop the virtual prototype of a tandem pattern double-lever wiper system, which is designed in the concurrent engineering concept, by integrating the control system in the mechanical model. To drive the mechanism, a DC motor is used, so that the objective is to control the angular velocity of the motor crank, which is perturbed with the crank turning moment. This torque is obtained having in view the mechanical model, on which act the applied forces. The input in the virtual model is the angular velocity of the motor crank. The output, which is transmitted to the controller, is the crank turning moment. Driving the wiper mechanism by using the motor torque is more realistic than attaching a motion generator to the input crank and driving the motion directly; by applying a torque, we can look at issues related to motor size in an actual mechanical system. In this way, virtual measurements can be performed, in any area and for any parameter; this is not always possible in the real cases due to the lack of space for transducers placement or lack of appropriate transducers. This helps us to make quick decisions on any design changes without going through expensive prototype building and testing.
Keywords: windshield wiper, dynamic model, control system, virtual prototype.