Fig. 3B Software Control Diagram - Curtis 1222 Manual

2 — INSTALLATION & WIRING:
Fig. 3b
Software control diagram.
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2 9 J A N U A R Y 2 0 1 3 D R A F T
Controller Wiring
device input to its counterpart (steering to steering, feedback to feedback). If
any of these input pairs do not match, the 1222 begins its fault sequence to
bring the vehicle to a stop.
As shown in the software control diagram (Figure 3b), the safety critical
parts are included twice to provide redundancy:
· two microprocessors
· separate paths to each micro for the command and feedback signals
· cross checks on the normalized steer command
· cross checks on the normalized wheel position.
A following error check ensures that the wheel position tracks the steer command.
Although not shown in the wiring diagram, the analog inputs can be
used for single sine/cosine sensors or sawtooth sensors instead of for redundant
pairs of pots. Each single sensor has two levels of fault detection, which provide
redundancy; see description of Tolerance parameter in Sin/Cos Sensor menus
(pages 26 and 41) and in Sawtooth Sensor menus (pages 28 and 42).
The wiring diagram (Figure 3a) is designed for generic applications and may
not fully meet the requirements of your system. You may wish to contact your
local Curtis representative to discuss your particular application. In cases where
the wiring deviates from the wiring shown in Figure 3a, it is up to the OEM
to evaluate the overall system safety.
Curtis 1222 Manual,
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