i think vex has a linit on how small it is possible to make a transmissio. yours is quite small, but the 84 tooth gears make it the first with them iāve seen
i think one of the lesser points of your robot is that it is just shifting on one side, which doesnt make sense to me. each tiime you shift, the robot is going to have to force two sets of gears to mesh. it would make sense if both sides were powered by an individual motor, but you have it needing only a common shaft connecting the rear wheels since they cant possibly turn differently. otherwise, i like the shifting mechanism.
How does it turn without a differential? Iām guessing the back two wheels skid when your robot turns, since both back wheels are going the same speed?
The way iām trying to approach it is to make a small gear box (I have made it but i had to take it apart) and then attach the output gear of it to a differential that is attached to the back two wheels, and a motor to the input gear of the gearbox. That way, you wouldnāt have to go through the trouble of lifting your robot upside down every time you want to work on the gears.
But Iām also thinking how the shifting would work. I remember one team used a very complex shiftable gear ratio for their robot.