My father has a cat 330b which does not always like to engage its gearbox. Many hours sitting waiting for the damn thing to start working. This seems to be a common failure on these cat machines. I got me wondering if it is possible to controller the gearbox externally using a arduino or raspberry pi instead of the cat brain. I guess you would need to 'snoop' the signal with an oscilloscope to see what signals the original cat controller is sending to the gearbox and then work from there. If you search youtube for reverse engineering and oscilloscope you will see example of similer setups to find out what signals are being sent. A lot of modern forklifts/tractors are prematurely scrapped because of shoddiness in the electronics. Its frustrating to not be able to easily hack these things as the mechanical's are usually sound in a lot of cases. Has anyone tried something similar? How complicated is the shift rail movement. does it need to be in sync? I guess it will be a proportional servo of some kind and the voltage/current is varied to achieve different positions?
Please provide a little of your background and experience. This is not a job I'd recommend to anybody, it's just not worth your time usually. It sounds like you understand the electronics of it better than I do, but how would I know? Are you sure you understand the hardware of this transmission? Specifically, is this a powershift transmission? I'm not sure if this "shift rail" exists, just guessing.
I have no experience with the CAT machines, but with ZF gearboxes the logic isnt too complex. one coil for forward and reverse. then a couple for the speeds. The logic is built into the shifter. if there is a computer it probably monitors shaft speed to prevent the operator from doing something stupid like dropping into reverse while going 20mph. ISZ