My thoughts were that with the gears in my truck, the workload I intend to use it for, and the torque band of my engine, the low range of the Brownie would be of seldom use.
That being said, any mechanism that can provide a simple forward-aft input to the drive/overdrive input on the Brownie would be sufficient.
In order to make life easier and eliminate the need to shift two sticks, what I had envisioned was a shift knob that had a mechanical lever toggle on it to push and pull a cable that connects to the drive/overdrive input to the Brownie. Essentially a lift of a fore-finger paddle to shift one way, and a push of a thumb paddle to shift the other way.
Obviously it would take a pretty stout tug of the fingers to overcome the input force required to shift the Brownie. This was my reasoning for wanting to use 'helper' solenoids. Since solenoids aren't a direct mechanical couple (just magnetic force pushing a rod) like a gear reduced linear actuator, as long as I didn't size them too large,, all they would be doing is providing a helping push to my finger inputs. Also, since there's no mechanical couple, if I was scratching the gears, all I'd have to do is let off the button and the push force from the solenoid would go away.
To get the electrical input to the helper solenoids at the right time, I'd simply place the buttons on the respective finger paddles such that when I push the thumb paddle with my thumb, I'm also pushing the button for the assisting helper solenoid. Likewise, when I'm pulling the other paddle with my fingers, I'd also be depressing the button for that helper solenoid.
I think it would still work without synchronization, but I like the idea of putting a spring in series such that the spring is what moves the input to the Brownie.
As an additional safety to ensure I didn't inadverdently push a button and activate a helper solenoid when you didn't want to, I could put a switch on the clutch pedal (like a brake light switch on a brake pedal) that would have to be depressed for power to go to the shift buttons.
It's almost too easy......
