Troubleshooting - fischertechnik Mobile Robots II Manual De Instrucciones

Conclusion:
As soon as we take at look at the program, we immediately recognize the
already known program strategy. A state variable controls the behavior of
our driverless transporter.
Using the refined programming techniques you have acquired, you can
implement multifaceted controls. The driverless transport system
demonstrates the possibilities, which the combination of fischertechnik
construction kit with the Intelligent Interface provides. Starting with simple
mobile robots, you have reached a state, which hardly differs from industrial
control engineering.

5 Troubleshooting

Experimenting is fun, but only as long as everything functions well. The
best would be if everything succeeded at first try. Unfortunately, this is
usually not the case.
You only know whether you have understood a mechanism precisely if a
model does not work and you find the error immediately.
With mechanical errors, you can still see (assembled incorrectly) or feel
(runs hard) something. When there are electric problems in addition, it
becomes more difficult.
Professionals use a number of very different measurement instruments for
troubleshooting (searching for errors), for example, voltmeters or
oscillographs. Not everyone has such equipment on hand. Consequently,
we want to try to pinpoint errors and correct them using simple means.
Before we start with the experiment, you have to put together a few
components from the fischertechnik construction kit. These are essentially
cable connections. The supplied plugs are connected to the individual cable
sections here.
First, you cut the cable. Measure the given lengths and cut the sections.
Before you cut, check very carefully to make sure the lengths are correct.
Then you need to test each cable. You need the accumulator and the lamp
for this. If the lamp lights after it is connected with the accumulator, the
cable is okay. If the color assignment is also correct – red plug with red
cable and green plug with green cable – put the cable aside and check the
next one.
If the program (including the one supplied) does not work with our model,
start "Check Interface". This auxiliary program lets us test inputs and
outputs separately. Each sensor must trigger the corresponding action on the
interface here.
After you check that, you know that all the electric connections should be
okay. Switch the actuators on and off individually via the motor control but-
tons. If everything works here too, look for the mechanical cause.
Loose connections represent bad errors. On one hand, connection plugs can
be loose in the sockets. If this is the case, the contact springs of the plug
are widened a bit using a small clockmaker screwdriver. Be careful, because
widening them too much can result in breaking the contacts or make it very
difficult to plug them in.
Another cause of loose connections is created by loose terminal connections
on the screw-in spots of the plug. Screw them tight carefully! You can use
this occasion to check whether any of the thin cooper wires have broken off.
If there is an unexplainable outage during operation, an almost empty accu-
mulator can be the cause. The voltage decreases briefly when a load is
switched (motor on), and then a reset is triggered for the computer on
the interface. Such an error is difficult to find, because the program always
functions correctly at first.
If errors occur in programs you have written yourself, which you cannot
explain, install a supplied program, which is as similar as possible to yours,
to rule out electric or mechanical defects.
If you are still not successful in finding the error, you can always contact
the fischertechnik service department.
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