OXTS RT1003, Руководство пользователя

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the position measurements at the precise moment of the trigger. Camera mode provides a
method of achieving this.
To enter camera mode, configure a trigger as an output, and set the distance to less than one
pulse per metre. A signal will be generated according to the specifications above at the
distance interval defined by the PPM settings. At the same moment the trigger signal is
output, a position measurement will be internally generated and logged alongside the regular
measurement data. To generate a real-time message in relation to the camera trigger, it is
necessary to select the
Output on camera trigger option on the Ethernet configuration
window.
Wheel speed input
The wheel speed 1A input (J5-3) accepts TTL pulses from an encoder on a single wheel. An
encoder from a gearbox should not be used, and simulated TTL pulses (e.g. converted from
the CAN bus) should not be used either. The timing of the wheel speed input pulses is critical
and nothing should cause any delay to them.
The RT1003 also accepts signals from quadrature wheel speed sensors. When using
quadrature sensors, connect one channel from the quadrature sensor to wheel speed 1A, and
the other to wheel speed 1B input (J5-5). The odometer input should be configured as per a
normal wheel speed sensor—the RT1003 will automatically detect the use of the quadrature
sensor.
The wheel speed input requires less than 0.8 V for a low pulse and more than 2.4 V for a high
pulse. Limited protection is provided on this port, however the input voltage should not
exceed 12 V.
Wheel speed input signal characteristics:
• 0 V to 12 V
• low < 0.8 V
• high > 2.4 V
The wheel that is used should not steer the vehicle. The RT1003 will assume the wheel travels
straight.