Quote:
Originally Posted by Adam.garcia
Can you please elaborate on how I should go about ensuring that I design the high gear to slip at stall?
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If you're designing the wheel to slip instead of stall, the force the gearbox can exert on the ground through the wheel should exceed the maximum frictional force that the ground exerts on the wheel. The maximum gearbox force is a function of the motors' torque at stall. The maximum frictional force is a function of normal force (itself a function of weight) and frictional coefficient.
If you're designing the gearbox to always shift into low in case of a failure, you should characterize the possible failures and try to deal with them. This isn't easy for shifting mechanisms that don't return to a home position (e.g. servos) during a malfunction, and is also difficult if you can't walk up to the robot to override a malfunctioning valve (which you can't, at least not during a match). Since redundant actuators and control channels aren't really feasible under most circumstances, taking this design approach will invariably lead you to compromise—but that might be good enough.
Quote:
Originally Posted by Adam.garcia
Are there formulas/a calculator/white paper that somebody has written describing this phenomenon?
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John V-Neun
wrote one, and has
updated it over the years. It's very useful. Others have written similar tools (like
this and
this), but I haven't tried them.
Quote:
Originally Posted by Adam.garcia
I'm using Blue Nitrile Tread from McMaster. However, I do not know the coefficient of friction.
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Probably about 1.0 on carpet (an educated guess). See
here for a bit more information.