pic: Team 2220 Blue Twilight Octocanum Offseason Project

[Madison]

Originally Posted by PAR_WIG1350

This is yet another solution with its own pros and cons to consider. While lighter, it could also be more complex and more difficult to actuate due to the additional weight (not an issue with some methods, but if it is retracted with springs, it might not be worth it).

All possible solutions should be evaluated to determine which is best for the team and its goals.

Imagine moving the pivot outside the two wheels in the module, where 'o' is a pivot, 'X' is a mecanum wheel and 'x' is a traction wheel:

o -- X -- x

This arrangement eliminates the need to lift the modules at all -- either by spring or by other actuation. The weight of the robot itself will cause the module to rotate about the pivot point; you simple need a hard stop somewhere after the traction wheel comes off the floor to stop the module from over-rotating and letting your frame hit the ground.

You can make this sort of thing work by either integrating the gearbox entirely or by continuing to use the pivot point as the link between gearing in the fixed gearbox and gearing to make the wheels spin.

I have a CAD model at home of the module I've been refining. It's not quite done yet, but it is based upon this idea and uses an integrated gearbox. If the above description isn't clear, I'll post a picture when I get home later tonight.