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Unread 02-04-2012, 19:19
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Nathan Streeter Nathan Streeter is offline
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Re: Moment of inertia and turning performance

Quote:
Originally Posted by icyplanetnhc View Post
With regards to method of using a 6WD as a short-base 4WD with 2 additional wheels, this is something that we've considered last year, but I believe we chose against it because it might've made aiming on one side of the robot, either the scoring grid or minibot tower, difficult (this was before we chose to use "alignment legs" at the bottom of the robot). In addition, if our robot's turning axis is biased to one side, other robots may have a large moment arm to turn our robot.
While it would make aiming on one side of the robot consistently harder since the point of rotation would be farther from one end of the robot, it isn't actually very different from having the "standard" drop-center 6WD... The drop-center 6WD is, to a degree, just two short 4WDs that are "randomly" switched between. From my impression, the drop-center 6WD rarely actually turns around its center wheels, but is usually turning around a point between one of the sets of 4WD. I would wager that most drop-center 6WDs are actually easier to spin than most "4WD+2WD" drive trains. Since the weight in a 4+2 is more firmly placed on four of the wheels, it seems like it might be more resistant to turning; however, that is conjecture rather than experimentally-verified fact...
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Student: 2006-2010 (#1519)
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