HOKUYO AUTOMATIC UAM-05LP, Руководство пользователя

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Document No: C-61-00003-3
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3.6 Incremental encoder
In UAM there are 2 pairs of encoder input terminals for connecting 2 units of dual channel incremental
encoder signals. Area will be switched depending on the encoder speed. Direction of travel is detected by
encoder's phase A and phase B signals having the phase difference of 90°. Speed and rotating direction of
both encoders are constantly monitored to detect abnormal travel and stop the AGV.
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Incremental encoder output signals should be connected to the respective input terminals of UAM. There
are two patterns of signals generated by the combination of Phase A and Phase B of encoders depending on
the direction of travel (Figure 3-10). In the first pattern, Phase B is 90 degrees ahead of Phase A wherein, at
the rising edge of Phase A, state of Phase B is “H”. This pattern is considered as positive direction (forward
motion). In the second pattern, Phase B lags behind Phase A by 90 degrees and the state of Phase B at the
rising edge of Phase A is “L”. This is considered as negative direction (backward motion).
Figure 3-10 Input signals from incremental encoder