Quote:
Originally Posted by ExarKun666
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1) Which drive looks better for this competition?
2) What are the pros and cons of A?
3) What are the pros and cons of B?
4) Suggestions that we should take under advisement, and any other comments.
TY to all who respond! 
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1. It depends on the location of the cg and whether the wheels are coplaner or some set is dropped. The trailer is effectively part of the robot.
2. See (1). What do you expect the doubled wheels to do for you?
3. See (1). What do you expect the crab wheels to do for you?
4. I believe that what the GDC is trying to do with this years game is to force teams to do the physics and math and understand all of the forces at work. They have effectively created an environment for which past rules of thumb and past experiences and intuition may not apply. But the laws of physics still apply. Use them to engineer your robot. As you get to understand the physics insights will start to appear.
OK, you have a couple of potentially viable configurations. Put the trailer in the picture. Stick the cg in some realistically attainable envelope and start calculating with the cg in the center of that envelope. What net force will the robot have? What turning moments will the robot have? Move the cg to the corners of that envelope and recalculate. Does it still work?
The traditional steps in evaluating design concepts are:
1) Does it work well on paper. If not, it still might work in the real world but it's usually not worth the risk. Engineers don't build things that don't work on paper (unless the're software engineers

)
2) If it works well on paper, confirm that your assumptions and calculations are valid and that it is likely to work in the real world as well.
3) Is it feasible to complete in the allotted time, i.e. detail design, build, test, etc.
4) Does it meet all the requirements of your application (i.e.) your selected strategy?
5) Is it likely to be competitive? (in the commercial world this is often a life or death parameter. In government nobody cares. In FIRST everybody is a winner.)
It's still early. Do the math. If you need help with the physics or math just ask.