Quote:
Originally Posted by Cory
Not to take anything away from the Robonauts, who clearly have a great design, but it seems like the decision to do what 148 did was simply out of necessity.
If you want to go 20 fps you need 6 motors.
If you need 6 motors, you have to do coaxial crab.
If you want to save weight/complexity, you use 3 wheels.
If you use 3 wheels, you have to use all 6 motors in one gearbox.
I think both are each very much their own designs.
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Quote:
Originally Posted by Morgan Gillespie
You may wish to check up on the factuality of some of these statements.
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Morgan,
Although your point is well taken, you may want to be less vague with your statement. If you believe that some or all of Cory's statements aren't valid, specifically address them with your rationale.
I'm not trying to single you out, but lately there's been far too many posts where people make claimss without any real justifications.
As for the meat of Cory's post, I'll attempt to point out the flaws that I think Morgan was trying to get at.
- Although not impossible to go 20 fps without 6 motors, it is incredibly difficult to so with a typical FIRST robot. Unless your robot is significantly lighter than usual, or uses a very low traction wheel, issues such as breaker tripping and battery power become quite serious when only using four motors.
- If trying to do a swerve with 6 motors powering your modules, coaxial is by far the easiest way to do it. As you increase the motors in your system, having to rotate them with the swerve module becomes cumbersome. (In 2004 we used two two-motor swerve modules to drive our robot. Designing our modules such that they remained compact was a significant challenge.)