About Building Your Model Correctly
Consider the following tips as you build your model:
■Use the Crawl, Walk, Run Approach - As explained in the
Modeling Process, you should start out building a simple model and then add complexity as you are sure that the simple model simulates correctly. For example, if your physical system has nonlinear bushings, start out by creating linear bushings. After you've simulated the linear bushings, change them to nonlinear bushings. Also, be sure to debug your model as you build it as explained in the later sections in this chapter.
■Make Smart Modeling Choices - The design of a virtual model follows the same principles as the design of a physical mechanical system. You want to be sure to make it simple. You want to be sure that it contains the smallest number of parts and mimics the behavior that you are studying in the physical system. Although Adams View gives you the power to mimic the behavior of your entire system, it is often better to only focus the system behaviors that you want to study.
Be sure to ask yourself many questions as you build your model, including:
■What parts do I really need to include? You should only include those that affect the behavior of the model. For example, ask yourself whether an anchor plate really matters in the virtual model.
■What forces do I include?
■How do my parts really interact?
■How can I validate my model? Is the model required to accurately portray behavior trends or is absolute accuracy required?
Those of you with a finite element analysis background may want to consider whether or not certain parts need to be modeled as flexible or can be approximated as rigid. Defining parts as rigid is easier and provides a good first step even if you decide to convert them to flexible bodies after your initial simulations are running smoothly.
Likewise, those of you with a CAD background may want to pay close attention when selecting which parts are required for your mechanical model. You rarely need to include every nut and bolt from your physical system or your CAD assembly.