September 2022 - 21

era. Service information revealed this system
will not work below 45 mph and is supported
by the camera located at the rear of the vehicle.
This is a SAE J3016 Level 0 vehicle, which
means the system will only provide visible
and/or audible warnings to the driver.
The rear camera is also used to support
p Figure 2- 2014 Rogue rear camera calibration update
blind spot warning (BSW). Since this is a
critical input for the proper operation of
both systems, the camera is supported by a
washer and blower system aimed at keeping
the camera lens clean. In the event of low
washer fluid, both systems will be temporarily
disabled until the fluid reservoir is
refilled. When calibrating the rear facing
camera, please refer to bulletin NTB14-072
titled: " 2014 Rogue; Target board placement
for rear camera calibration. " Under the notes
section, you will find the following statement
about operation:
" The Rear-View Camera monitors the traveling lane. It transmits
the camera image signal to around view monitor control unit for the
Lane Departure Warning (LDW) system. "
The bulletin states the distances listed in the service manual
are incorrectly supported by the following graphic (Figure 2).
p Figure 3- Mazda Smart City Brake lidar sensor in operation
it's likely that the camera system is providing parallel layers
of vision support simultaneously.
For example, a camera may be tasked with performing lane monitoring
operations where a special filter is applied to the signal for processing
lane markings and measurements as they relate to the vehicle
they're mounted on. At the same time, there may be another service
running that performs object detection and classification, and there
may be a pose-detection program running tasked with estimating/
predicting human movement around the vehicle. Humans on foot
and on bicycles are considered vulnerable road users (VRUs) and
are a high priority within the onboard DAS (Figure 1).
Cameras mounted high and center behind the windshield are
mostly used for lane keeping and object detection/classification.
However, I recently had a 2014 Nissan Rogue in the shop with lane
departure warning (LDW) without a windshield area mounted camRADAR
SYSTEMS
Radar sensors use electromagnetic radio waves to sense the distance
to objects within its cone of rays by measuring the time of
flight (ToF), and the incident angle between the transmitting (Tx)
and receiving (Rx) antennas. Typically, the radar sensors used for
adaptive cruise control (ACC) operate in the 77-81 GHz range.
What this means is these radio chirps are being transmitted in
the order of 77-81 billion times per second.
There are highly complex algorithms (usually taking place
within the sensor) before its data is shared with other systems
on the vehicle. The radar sensors used on the rear corners of the
vehicle mostly operate at lower frequency ranges (24 GHz). Radar
sensor that resides behind body panels is tuned specifically for
that environment, so any changes to the body, repair, paint, etc.
could negatively affect its operation. Consult service information
for more information.
Additionally, these sensors are very delicate and most have a
statement on the body saying they should be discarded if dropped.
If you find yourself addressing one of these sensors that has been
in a collision where the sensor and/or surrounding area suffered an
impact equaling the shock from a drop, then a new sensor should
be installed and properly initialized and calibrated.
LIDAR - LIGHT DETECTION AND RANGING
Lidar works like radar, as it's using ToF of the near infrared light
beams scattered out in front of the sensor. Since infrared is outside
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September 2022

Table of Contents for the Digital Edition of September 2022
