> Hi there everyone
> I'm working on an electronic shifting system for a Formula SAE car

I am very likely going to look at implementing a "tiptronic" gear
shifting system in a car. I have no firm methods in mind at present.
Some systems definitely use solenoid actuation. One disadvantage of
solenoids is the very variable force variation as air gap changes with
minimum  force at maximum gap at a point when you'd often like more
force. It's certain that solenoids can be made to do the job (as they
are used already in some systems).
Googling on "solenoid design" may help. This may be a useful *start*
http://www.mhhe.com/engcs/electrical/cathey/matlab/ch3/soldes.m
Note that detailed design depends on the specifics of your arrangement
(magnetic path details at each stage of the activation proves.)

This may help but it's not complete

        http://www.cliftronics.com/design_guide.html


An alternative, with its own problems, is pneumatic or hydraulic
control - Ferrari use the latter AFAIK on their manual gearbox
sequential shifter systems. Small pneumatic cylinders can have high
and consistent force and be controlled with electrically operated
valves. Providing an air source may be annoying.

An electric motor solution MAY be quick enough and would provide ease
of force multiplication with a gearbox, at the expense of speed.

> The other idea I was looking into was using a solenoid originally
> designed for a lower force, but feeding it a much higher initial
> current to get it moving faster, giving it more momentum for the
> portion of the stroke that would require a stronger force.

Definitely helps. Using lower voltage solenoids on 12v and deriving a
low voltage rail for hold in my be easier than producing a higher
voltage for fast activation.




        RM

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