The electro-mechanical column shifter design is coming along quite well. I have the basics of how the mechanical system will ratchet, and turn the encoders to the proper degree for each gear, sorted out. As per my normal design process, I did all that in my head, with the assistance of a lot of chicken scratch sketching, and have now started modeling the ratchet and pawls, then the gears, then the housing - yes, I plan to design and make almost every piece (except for fasteners, etc)! It's going to mount right on top of the steering column, and have a clear cover, like a watch face, so you can see the mechanical commotion inside. Hmmm, I'd better make sure people can actually see it way down there, and under that impossibly low roof.
The goal is for it to feel sort of like cycling the bolt, or pulling the trigger, on a really expensive rifle when you pull the "paddles". Beside the mechanics to get the encoders to turn to the right positions, that's what all the design process has been about. Mostly all metal components inside, directly connected to your finger tips, and very smooth distinctive action, with well defined releases, catches, and stops. When you first pull, you'll feel it release the pawl for that direction, then feel yourself winding all the gears up to speed, then just as it begins to gain momentum, and inertia begins to take over, the pawl reconnects and brings it all to a dead stop - gear engaged! All that happens in about seven degrees of rotation for the shifter and ratchet/pawl, but there is a flurry of activity throughout the rest of the assembly.
I need to develop a feedback loop, to interrupt the encoder's signal to the steppers, if the transmission doesn't go in gear. My first thought is simply sensing the resistance - what happens when a CNC machine encounters something it can't move - the program crashes - but less code, and more simple electrical circuit. I think...
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