|
PREFACE:
Joysticks are a matter of personal preference in handle,
button layout, and gimbal feel. If you are left handed, your
choices are limited unless you can customize your own. One major
difference in joysticks is quality and reliability. These two
factors separate the field rather dramatically. Do not expect the
most expensive stick to be the most reliable or highest quality. The primary considerations here being the technology used for the
encoders, the gimbal design, and the materials used. Some people
will never have to worry about their joystick, others like myself
are "power" users who can wear out a joystick in a
couple of days of game play. Other sources of problems are
related to the computer's game port and software.
ENCODERS:
A joystick has two axes, left-to-right and forward-to-back.
Two axes dictate two encoders. The primary technology employed
today for encoders is the potentiometer. A potentiometer is a
variable resistor that is made of a carbon impregnated surface
and a metal wiper. As the shaft of the potentiometer is turned,
it's resistance changes thereby allowing the game port to read a
value that corresponds to the position of the joystick.
Potentiometers wear out. The rate at which they wear out depends
on the gimbal design, the user, and the potentiometer. Some
potentiometers are rated in the millions of cycles. But even
these will not last if the gimbal design is incorrect or the user
moves the joystick too rapidly. Remember, the metal wiper
"wipes" across the carbon impregnated surface, every
time it "wipes", it removes a little bit of carbon. Eventually, all the carbon will be "wiped" off and the
potentiometer will no longer change it's value when turned or
"wiped". However, as the
carbon is "wiped", the resistance in that
"wiped" region is forever changed. Some joystick
manufacturers started putting a dielectric grease on the carbon
surface in hopes that this would reduce wear. All that did was
hold the carbon that was "wiped" off in the grease
causing even more abrasion and more resistance fluctuation. Signs
that your potentiometers are wearing out are best described as
jumpiness, and the inability to maintain a center position. Real
critical when lining up a torpedo run on an Imperial Star Destroyer in XWING.
At this point, you have several choices, live with it, buy
another, replace the potentiometers, modify it, or buy a joystick
that does not use potentiometers. As you can tell, I've been
there, done that, got the tee shirt, and didn't like it worth a darn.
LESSONS LEARNED:
I started out with a joystick that had (and to
this day still does have) the best look, grip feel, and button
positions for my taste, specifically the THRUSTMASTER Flight Control System (FCS).
After about three days of XWING, I
couldn't center my craft to lock onto a TIE Bomber at long range
with a concussion missile because my ship kept jumping around. Then it got
to the point where if I pulled back on the stick slightly, I
would take a sharp nose dive. So, a call to tech support and they
sent me a bag of replacement potentiometers and velcro…the
velcro was to be used to put the stick back together instead of
using the allen head screws!!!! After about two bags of
potentiometers, an improved version of the original pro version
that used a geared gimbal, and two more bags of potentiometers, I
decided to make a change.
At that time, the only encoder
technology on the market was potentiometer based so I decided to build an
optical-analog encoder that would last forever. I printed two circles with
a gray scale pattern on a sheet of plastic transparency cut out the circles,
fastened them to the end of the axes shafts, and put diode &
photo-transistor pairs on each. The diodes were arranged to shine through
the gray scale transparency circles onto the photo-transistors. As the
shafts rotated with stick movement, the gray scale pattern disks rotated and let
more or less light through to the photo-resistors, thus changing their
resistances.
I modified the
joystick and rudders, tuned it, and was very happy. It worked extremely
well and the encoders would last for a very long time. All went well
until the springs in the gimbal started to break. The velcro was no joke, it was a real
good idea. The springs were loops with straight ears sticking out.
The ears would break off. After two or three bags of springs, I was now
looking for a different gimbal design. One that didn't have a design flaw.
Just when I was thinking of designing my own gimbal, along came the PC-OPTIX, I really liked this
stick because it used optical encoders that I knew wouldn't wear
out and it used coiled springs for stick tension which I knew
would last longer than the loop springs of the modified THRUSTMASTER Pro
FCS. The only problem was the handle was not quite up to my
standards, so a little cutting and gluing and voila, a PC-OPTIX
with a TM handle, and I was in Heaven.
Then the plastic gimbal of the
PC-OPTIX started wearing out. And wires inside that connected the
handle buttons to the circuit board that passed through the
gimbal started pulling off. This also happened to an unmodified
stick as well…another design flaw story. So it was either
on to building my own gimbal or trying a different stick.
Then came the Microsoft Sidewinder Pro. At this time, I am using the Microsoft Sidewinder 3D
Precision Pro without a problem. I have heard of people breaking springs in this stick,
but this has not happened to me yet. All in all it is a good
stick except for the handle design, I really like the old F-4
design. The handle on this stick is close, but not exactly the same.
But alas, the gimbal in this stick is plastic as well and
is starting to wear slightly…maybe I'll still have to build a metal
ball-bearing gimbal and optical encoder stick one of these days
that will last.
GIMBALS:
The gimbal is the mechanical interface that translates the
joystick motion into rotational motion for the encoder. The
original TM Pro FCS used the potentiometer bushings as the main
load carrying bearings for the stick. The improved TM Pro FCS
(sold today) employs independent load bearing bushings and drives
the potentiometers by a geared interface. This helped reduce the
potentiometer wear significantly. However, the springs used in
this design are prone to failure and the load bearing bushings
wear. The PC-OPTIX is prone to wires coming loose from the
circuit card, even on my brother's whose handle was never
modified, and it has a plastic gimbal mechanism that also wears. The Microsoft Sidewinder 3D Pro has been the most reliable.
It's
handle is small and uncomfortable for me and it's plastic gimbal
is starting to wear as well, but it has been the best joystick I
have owned including the CH Flightstick Pro which suffers from
potentiometers. The Sidewinder uses an optical-analog encoding
scheme. To me, the perfect joystick would be a TM FCS metal
handle (by the way, the black plastic on this handle will wear
off onto to your hand) a metal gimbal that uses ball-bearings and
standard coiled compression springs, and optical encoders.
Game Ports:
The game port is a simple Analog to Digital (A/D)
converter. It takes an analog voltage and converts it to a
digital number. Most game ports found on multi-Input/Output (I/O)
cards and sound cards and even motherboards are not adjustable. This can result in certain games from not recognizing the
presence of your joystick. The game port has to be adjusted to
your computer's Central Processing Unit (CPU) and bus speed. There are a few adjustable game ports on the market.
My favorite
is the CH products Automatic Gamecard III. This game card does
not use a Terminate Stay Resident (TSR) program. It uses a stand
alone program that sets the game card speed and can be put in the
autoexec.bat file, but it does not stay resident in memory. The
TM game card and a few others use a potentiometer to adjust the
speed and you have to run joystick calibration software provided
with the card to adjust it properly. I do not like this type as
the potentiometer is prone to little fingers and my cat
"adjusting" it from time to time. Plus, the CH product
is automatic, it will set itself or you can override it if you
are not satisfied. The game ports on the newer sound cards seem to work
well.
|
