Safety starts with vision by Yu Rong

The Future Traffic Sign Recognition System

Safety Starts with Vision

Safety Starts with Vision The Future Traffic Sign Recognition System

ISBN 0-9000000-0-0

School project was directed by David Hake, Academy of Art University. Book design, text edited, concepts and art direction by Yu Rong cn.rongyu@gmail.com www.yurongdesign.com

79 New Montgomery Street, San Francisco, CA 94105-3410 Tel: 800.544.2787 Fax: 415.618.3545 Email: online@academyart.edu www.academyart.edu

All rights reserved. This book or any portion there of may not be reproduced or used in any manner whatsoever without the express written permission of the publisher except for the use of brief quotations in a book review.

Font: Fedra Sans, Fedra Mono Printer: Epson Stylus Photo R2880 Inkjet Printer Stock paper: Epson Premium Presentation Paper Matte, 8.5x11 Inches, Double-sided Binding: Chumâ&#x20AC;&#x2122;s Design & Print chumsdesignandprint.com

Statement

Traffic Sign Recognition (TSR) system is used to regulate traffic signs, warn a driver, and command or prohibit certain actions. A robust automatic traffic sign detection and recognition can support and disburden the driver and significantly increase driving safety and comfort. Automatic recognition of traffic signs is also important for automated intelligent driving vehicle or driver assistance systems. This book introduces the design of a future traffic sign recognition system. It includes seven features that are smart real-time recognition system, speed limited, distance detection, GPS head-up display, road condition, language and voice prompt.

Table of Contents

01 Introduction 04 Smart Real-Time 12 Speed Limited 18 Distance Detection 26 Light System 34 Smart Heads-Up Display 42 Road Condition 50 Conclusion 54 Reference

Introduction

Safety Starts with Vision Introduction

Introduction

A Traffic Signs Recognition (TSR) system is part of a modern driver assistance system in cars. It allows to optically recognize traffic signs, speed limitation signs, while providing motoring information to the driver. The image processing and color analysis play the central roles in the traffic signs recognition[1].

Safety Starts with Vision

Figure 01

Introduction

0 2 / 03

It shows the basic functioning of the TSR application. Relevant areas in the video image are recognized before those areas are classified in a second step. The grabbed image frame in Figure 1, taken from a video used as test sequence during the design, shows a traffic sign for a speed limitation of 50 km/h, which is recognized and classified correctly. Another traffic sign for pedestrian/biker way, which is not included in the classifiable coefficient subset yet, is preprocessed for an image enhancement and shape edge detection, but not classified. A TSR system generally consists of four main modules: Camera, recognition, classification, and display module.

Figure 02

It depicts the functional overview. The camera module grabs image frames and generates an image or video stream. Within the recognition module, image preprocessing and enhancement is performed and afterwards a shape detection stage allows detecting circles. These circles can be found in image frames containing a speed limitation sign. These circles are subsequently classified using a template-matching algorithm based on a support vector machine. This classification stage allows to detect different speed limitations from ”30 km/h”, ”50 km/h”, ”60 km/h”, ”70 km/h”, ”80 km/h”, ”100 km/h”, ”120 km/h”, as well as prohibition signs like ”No passing”, ”No passing for heavy goods vehicle”, ”End of all traffic prohibitions” and ”End of passing prohibition”. Finally, the recognized traffic sign is displayed to the driver. The initial video or image stream data is based on byte-sized gray-level pixels. These pixels are scaled to floating-point data and the subsequent recognition and classification stages are performed using floating-point arithmetic. The support vector machine algorithms uses a coefficient field with about 800K data items for the classification procedure. The algorithms of the recognition and classification stage contain multiple loops and nested loops[1].

Figure 1 Traffic Sign Recognition System

SIGN NOT IN CLASSIFIABLE SUBSET

traffic sign

recognition

classification

Figure 2 traffic sign recognition

preprocessing

extraction

shape detection

classification

segmentation

display traffic signs

process

Smart Real-Time

Safety Starts with Vision

Smart Real-Time

0 6 / 07

Smart Real-Time

Smart signs analysis system will be the central idea of the future Traffic Sign Recognition System. Based on the technique consequences, it involves traffic light recognition system, lane departure warming, citiesâ&#x20AC;&#x2122; traffic conditions and human psychological reaction[2].

Smart Real-Time

audiâ&#x20AC;&#x2122;s online traffic light

information system

Audiâ&#x20AC;&#x2122;s online traffic light information system_ http://www.popsci.com/article/cars/audi-traffic-light-recognition-could-save-time-and-fuel

Safety Starts with Vision 0 8 / 09

A technological solution of the traffic light recognition system is allowing drivers to anticipate changing lights, and it helps saving fuel as well. The system works by reading the automated signals from a cityâ&#x20AC;&#x2122;s central traffic computer, and transmitting that information to the driver through the carâ&#x20AC;&#x2122;s Driver Information Display. At a red light, the system can count down the time remaining until a change to green, as well as prime an engine start-stop system to restart the engine five seconds

A technological solution of the traffic light recognition system is allowing drivers to anticipate changing lights, and it helps saving fuel as well. before that. While on the move, it can also sense whether a car will be able to make it through a green light and if not, advises the driver to start braking early, preventing abrupt stops. In the real world, Audi, a German automobile manufacturer, is currently testing traffic light recognition in Berlin, Las Vegas, and Verona. They declare the system is production ready, but it is pending government approval. Audi also believes this technology could save significant quantities of fuel in city driving, where the constant start-and-stop nature of traffic can hurt MPG (Mondetta Performance Gear). It could also help smooth the flow of traffic, which would make everyoneâ&#x20AC;&#x2122;s morning commute easier [3].

Safety Starts with Vision

Smart Real-Time

1 0 / 11

Secondly, the lane departure warning system alerts drivers when they unintentionally stray out of their lane. This helps prevent a dangerous situation, such as a driver falling asleep at the wheel. Lane Departure Warning can be switched on or off via a button. When active, it warns the driver with an acoustic signal and a blinking icon on the instrument panel. Lane Departure Warning uses a second signal processor and software to filter lines and longitudinal patterns at speeds above 50 km/h. This enables the system to recognize the traffic lane. By using specific algorithms that define the conditions in which alerts are given and by noticing steering wheel and turn-indicator movements – signaling an intentional lane change – the system is designed only to intervene at the appropriate moment.

Side Blind Spot Alert (SBSA) warns the driver of a potential imminent collision when changing lanes (active from 10 – 140 km/h). Ultrasonic sensors with a range of four meters at the front and rear on both sides of the vehicle constantly monitor the driver’s blind spots. As soon as another vehicle comes within range of the sensors, an orange LED lights up an icon on the outer edge of the respective rear-view mirror. If the driver activates the turn signal to indicate a lane change, the LED starts to flash and an acoustic warning signal is activated[4].

Speed Limited

Safety Starts with Vision

Speed Limited

1 4 / 15

Speed Limited

Fluid_ https://www.flickr.com/photos/appurupai/8416180214/

The Following Distance Indicator (FDI), which is activated automatically at speeds from 40 km/h, not only helps to prevent collisions, but also helps to avoid possible fines for not maintaining sufficient safety distance to the vehicle in front. The radar directly measures the distance to the vehicle ahead up to 150 meters[5].

In a car with radar determines the distance to the vehicle ahead. The central driver display shows the corresponding distance value in seconds: this indication strategy is in line with the regulations in most European countries, which define the safety distance in terms of time, not in meters. In Germany, for example, the minimum distance is 1.8 seconds - equivalent to half the distance of the current speedometer reading in meters, e.g. 50 m when driving at a speed of 100 km/h[5].

Safety Starts with Vision

Speed Limited

FDI Dashboard: simply choose the gap time or distance measured in seconds that you wish to maintain between you and the vehicle ahead, and the Following Distance Indicator will use radar to help you maintain it.

1 6 / 17

A driving separation indication system for a vehicle includes an imaging sensor, a control and at least one indicator. The control is operable to process an image captured by the imaging sensor representative of a scene occurring exteriorly of the subject vehicle and to detect another vehicle via processing of the image. The control is operable to determine a threshold interspacing distance in response to a speed of the subject vehicle, and is operable to determine a distance from

The control is operable to process an image captured by the imaging sensor representative of a scene occurring exteriorly of the subject vehicle and to detect another vehicle via processing of the image.

the subject vehicle to the detected other vehicle. The control is operable to at least occasionally actuate the indicator in response to the distance from the subject vehicle to the other vehicle being less than or equal to the threshold interspacing distance. The control may generally continuously determine the speed of the vehicle and the threshold interspacing distance to provide an appropriate threshold interspacing distance. Drivers which allow an insufficient distance between their vehicle and the vehicle ahead of their vehicle may cause a traffic accident if the leading vehicle suddenly slows down. In the event of the driver of the leading vehicle responding to a situation with hard braking, the driver of the following vehicle may have insufficient time to notice and react to the illumination of the leading vehicleâ&#x20AC;&#x2122;s brake lights, determine the required severity of braking, and decelerate sufficiently to avoid running into the rear of the leading vehicle. This error in judgment of a safe separation distance appears to increase at higher speeds, often resulting in catastrophic or even fatal accidents. The introduction of a center high mounted stop light (CHMSL) has greatly improved the rate at which the following driver notices the illumination of the leading vehicleâ&#x20AC;&#x2122;s brake lights. The present invention is intended to provide an indication or alert system which is operable to alert the driver of a following vehicle that the following vehicle is at a potentially unsafe distance from the subject vehicle. The threshold unsafe distance at which the indication system is activated may vary in response to the speed of the vehicle, the driving conditions and/or the like [6].

Distance Detection

2 0 / 21

Adaptive Cruise Control (ACC) helps the driver to maintain the selected speed while keeping a pre-set safety distance to the vehicle ahead. In addition to speed, the desired gap to the vehicle ahead can also be selected by the driver â&#x20AC;&#x201C; with three options available: far, medium, close.

Fluid_ https://www.flickr.com/photos/appurupai/8416180214/

Safety Starts with Vision

When ACC is activated, the radar constantly checks the distance up to a range of 150 meters ahead; the selected gap to the closest vehicle in the same lane is shown in the center screen of the display as well as the pre-selected speed[7].

Safety Starts with Vision

2 2 / 23

Distance Detection

ACC on/off requested braking

vehicle speed

host estimator

relative speed

preceding vehicle estimator

delay

vehicle model

range prediction

alert decision

range relative estimator

yaw rate

Driver alert for vehicle with adaptive cruise control system

phase space division & logic

situation severity threshold generator

visual alert

preceding vehicle filter

audible alert

Adaptive Cruise Control (ACC) is an optional cruise control system for road vehicles that automatically adjusts the vehicle speed to maintain a safe distance from vehicles ahead. It makes no use of satellite or roadside infrastructures nor of any cooperative support from other vehicles. Hence control is imposed based on sensor information from on-board sensors only. The extension to cooperative cruise control requires either fixed infrastructure as with satellites, roadside beacons or mobile infrastructures as reflectors or transmitters on the back of other vehicles ahead.

The impact is equally on driver safety as on economising capacity of roads by adjusting the distance between vehicles according to the conditions. Such systems go under many different trade names according to the manufacturer. These systems use either a radar or laser sensor setup allowing the vehicle to slow when approaching another vehicle ahead and accelerate again to the preset speed when traffic allows - example video. ACC technology is widely regarded as a key component of any future generations of intelligent cars. The impact is equally on driver safety as on economising capacity of roads by adjusting the distance between vehicles according to the conditions. A method of detecting a driver alert situation for an operating host vehicle that precedes a preceding vehicle, the method comprising the steps of: determining a difference in speed between the host vehicle and the preceding vehicle; determining a difference in a rate of acceleration between the host vehicle and the preceding vehicle; determining a range between the host vehicle and the preceding vehicle; detecting if an adaptive cruise control system is on or off; determining an alert need, based upon the difference in speed and the difference in acceleration, if an adaptive cruise control deceleration is sufficient for the host vehicle to avoid the preceding vehicle if the adaptive cruise control system is on, and if a possible situation exists where the host vehicle will not avoid the preceding vehicle due to predicted inputs from a vehicle operator if the adaptive cruise control system is off; and providing a driver alert when the adaptive cruise control is detected as on and the adaptive cruise control deceleration is not sufficient for the host vehicle to avoid the preceding vehicle, and when the adaptive cruise control is detected as off and the possible situation exists that the host vehicle will not avoid the preceding vehicle [8].

Safety Starts with Vision

Distance Detection

100km/h

Distance control assist system monitors the distance between your vehicle and the vehicles ahead, and regulates your speed. The ACC system decelerates your vehicle when necessary to maintain a safe distance between vehicles.

2 4 / 25

100-80km/h

80km/h

80-100km/h

constant speed control _no preceding vehicle deceleration_the preceding vehicle is slow maintain constant headway_follow preceding vehicle acceleration_the preceding vehicle changes the lane

Distance Detection is not only relates to on the road, but it also be

APA can be activated as soon as drivers slowly pass a row of cars at a

considered at parking. Advanced Park Assist (APA) puts an end to sec-

distance of 1.8 meters. As soon as a sensor located on the side of the

ond-guessing on those coveted parking spaces. It is a perfect tool

vehicle recognizes a space, it informs the driver via the central display

for car drivers who have difficulty parking in tricky situations.

and begins giving steering instructions. After the APA button has

APA makes parking easy: it finds spots into which the vehicle can fit and provides clear instructions via a signal on the dashboard. The main advantage of the system is that it recognizes spaces which are only one meter longer than the vehicle. Other comparable fully automatic systems need to find spots that are significantly longer than one meter before they start working.

been pushed, the system searches for a parking space on the passenger side. When the indicator is activated to the driverâ&#x20AC;&#x2122;s side, APA searches for a slot on that side. Distance control assist system locates in the front bumper, helps drivers control the distance between themselves and the vehicle in front of them. the system determines the following distance of the drivers, s well as the relative spend of both cars[9].

Light System

Safety Starts with Vision

2 8 / 29

Light System

Fluid_ https://www.flickr.com/photos/appurupai/8416180214/

Adaptive Forward Lighting resolves unclear optical obstructions though adapting its intensity and range to suit prevailing driving and road conditions with nine different lighting functions[10].

Safety Starts with Vision

Light Ssytem

3 0 / 31

AFL technology features a free-form cylinder automatically rotating in front of the xenon bulb, which has several precisely calculated contours on its surface to produce various light beam patterns.

AFL is based on powerful bi-xenon, gas-discharge headlamps. With conventional bi-xenon headlamps, the low beam light and dark boundary are provided by a bulb shield. Instead of this shield, AFL technology features a free-form cylinder automatically rotating in front of the xenon bulb, which has several precisely calculated contours on its surface to produce various light beam patterns. Bi-xenon headlamps project low and high beams from just one xenon bulb per headlamp. The light spectrum and intensity stay the same when switching between modes, thus reducing eyestrain. AFL headlamps also come with LED daytime running lamps. Compared to conventional low beam headlamps, these reduce fuel consumption because they require considerably less electrical power. LEDs offer an extraordinary service life that is up to 30 times longer than H7 halogen bulbs. The system features nine lighting functions. High Beam Light Assistant is an innovation in this segment and offers a considerable safety advantage when driving in the dark. High Beam Light provides maximum headlamp beam output and range. At speeds under 50 km/h, Town Light provides a wider, symmetrical beam with reduced range, helping drivers see pedestrians at the roadside better. Pedestrian Area Light is activated automatically at speeds of up to 30 km/h. Country Road Light provides a brighter and wider light cone to both sides of the road than a conventional low beam. Highway Light intensifies and slightly raises the headlamp beam when there is no risk of dazzling oncoming traffic and the smoother road surface causes fewer vehicle body movements. Adverse Weather Light is activated when the rain sensor detects a certain amount of moisture on the windshield or the wipers are switched on and off in rapid succession. Dynamic Curve Light ensures improved illumination around bends by swiveling the bi-xenon headlamps up to 15Â° right and left of the vehicle into the oncoming cur ve. Static Cornering Light illuminates an area to the right or left of the vehicle up to a 90 degree angle, improving maneuvering in poorly lit areas, such as on dark access roads[11].

Safety Starts with Vision

Light Ssytem

3 2 / 33

the beam difference between ECE, DOT, JDM, and harmonized headlights

There are three different headlight types. Parabolic is the light source

drive beam patterns without loss of light. This usually done by turning

hits a parabolic reflector that will determine the main focus of the beam.

the reflector housing in reference to the shield and you get the full

Then the front glass will disperse the light more to each side. Free form

‘opposite’ beam pattern. UK needs this ability to drive legally on the con-

is same as parabolic, but front lens is clear. Ellepsodials is light source

tinental Europe. This is why some cars for the UK market have projectors

hits a parabolic reflector, gets horizontally cut off in the first focal point,

where the rest of the world don’t. With a parabolic reflector, the ‘kick up’

then projected back straight again with a curved lens. Ellepsodials also

part of the lens has to be taped up.

goes under the name projector headlights. Reflector design is a common description of Parabolic and Free Form.

Projectors are normally not used in combined high/low beam setups. Clearly, it’s possible to have a movable shield and this is just what hap-

There has been a trend that more and more vehicles go away from the

pens with “bi-xenon projector” setups, but this would be very costly

traditional parabolic headlamp. The thick glass that are needed makes

in a econo car with halogen setup. A regular H4 or 9007 application is

it a looser in the game of efficient lighting. It seems like the majority of

much more cost effective.

auto manufacturer selects ellepsodials. They weren’t up to par in the first generation. The lower 180 degrees of the bulb output were practically not getting out of the housing. The second generation is designed with another focal point to increase efficiency.

Very simple, Bi-Xenon means that both high and low beam is created by the same HID bulb. A Bi-Xenon system can be based on reflector and projector design. The latter one is the simplest. Hella has a Bi-Xenon system that has a movable shield inside a projector unit. This is accomplished

Projectors create a much sharper cutoff than reflectors. Although some

by using a spring loaded solenoid ( just like in power door locks) or servo

parabolic reflectors can create pretty good cutoffs a projector will

motor with 2 positions. Bi-Xenon came on many cars in 2002.

always be better. This has the main advantage that projectors can be aimed higher than reflectors because no stray light (above the cutoff ) will exist to cause glare to oncoming drivers. This is especially important with high intensity light sources like HID and the new HIR halogen bulbs. Projectors can be designed to be easily switchable from left drive to right

The advantage compared to a traditional projector HID low beam/Halogen high beam is that you get HID low AND high beam. Bi-Xenon systems have additional flash-to-pass separate halogen lamps. Bi-Xenons System are a step up from regular low beam Xenons, since there will be better high beams. The high beams in a HID low beam HID/ halogen high beam

typical ECE typical DOT typical harmonized typical JDM

combination has a tendency to be degraded to a beam cutoff softener.

This is a future headlight system that will adapt to all kinds of conditions.

It is easy to get spoiled by the powerful low beam HID which makes high

It has various sensors that make headlights adapt light distribution

beams with 65W halogen almost dim in comparison. They should have

according to ambient light, speed, steering wheel position, and possibly

been 140W high beam. Bi-Xenons gives a better long distance view when

GPS coordinates. A common powerful Xenon bulb is placed away from

high beam is on. Bi-Xenons are not perfect either. Ideally, they should

the headlights. Light is transferred through thin fibre optic cables to hea-

have made foreground lighting weaker when switching solenoids over to

dlights, where they terminate in variable fresnel lenses. Rumors say

high beams. But that feature in non avail so far.

that Verio-Xenon will be available during 2002 from Hella for automobile

See OEM HID database for cars with this option. The downside with Bi-Xenon systems and traditional low beam Xenon systems is that illumination close to the car is too bright at high speed driving. This is one of the reasons why the “Vario Xenon” system is superior. Do not confuse OEM Bi-Xenon system with an aftermarked “Bi-Xenon HID kit”. This is described under the “HID kit” section. The intention is to move bulb away from headlamps into a common, very powerful source. Weight will be saved because fibre optic wires are lighter than copper. Amount of bulbs will be saved. Fibre cable is terminated into a fresnel type lense which shapes the beam output. There are a number of prototypes out there, but they’re still experimental. For a fullblown AFS lighting system (see further down), they’d be great, since the aiming motors would only have to move the light pipes, without moving the heavy, bulky fixtures. This would make the headlight “stylists” (and marketing people) happy too, since there wouldn’t be any ugly clearance gaps between the moving part of the headlight and the surrounds.

manufacturers. The future will tell if they are able to get production cost down. Volvo has been testing this system in their SCC concept car since 2001. The Adaptive Forward Lighting (AFL) concept was later introduced by Hella after Vario-Xenon, probably a better name and probably lower cost. It utilises a BI-Xenon projector unit to adapt to road conditions only according to speed and steering wheel position. The projector unit rotates up to +/- 15 degrees to each side. A second bulb and reflector will direct light 90 degrees sideways, which will help you see those dark pedestrians when you take a right turn on red. Mercury Sable, Cadillac and some other north American car models has similar function: A 25W bulb illuminates 50 degrees to the side when turn signal is on. AFL might be seen on a future Opel Vectra and Signum models, pending ECE recognition[12].

Smart Heads-up Display

Safety Starts with Vision

Smart Heads-up Display

3 6 / 37

Smart Head-up Display

The Heads Up Display transparently projects your speed, directions and collison warnings through your windshield, within your field of vision. With this feature, you donâ&#x20AC;&#x2122;t have to look down, so you will be able to focus on the road ahead[13].

Motortrend_ http://image.motortrend.com/f/roadtests/sedans/1307_2014 _mazda3_first_drive/52207489/2014-Mazda3-head-up-display.jpg

Safety Starts with Vision

Smart Heads-up Display

3 8 / 39

A typical HUD contains three primary components: a projector unit, acombiner, and a video generation computer.

A typical HUD contains three primary components: a projector unit, acombiner, and a video generation computer. The projection unit in a typical HUD is an optical collimator setup: aconvex lens or concave mirror with a Cathode Ray Tube, light emitting diode, or liquid crystal display at its focus. This setup produces an image where the light is parallel i.e. perceived to be at infinity. The combiner is typically an angled flat piece of glass (a beam splitter) located directly in front of the viewer, that redirects the projected image from projector in such a way as to see the field of view and the projected infinity image at the same time. Combiners may have special coatings that reflect the monochromatic light projected onto it from the projector unit while allowing all other wavelengths of light to pass through. In some optical layouts combiners may also have a curved surface to refocus the image from the projector. The computer provides the interface between the HUD (i.e. the projection unit) and the systems and data to be displayed and generates the imagery and symbology to be displayed by the projection unit. With a more advanced HUD, you can see your current speed, the color display also shows any vehicle warnings such as lane departure, your current setting for adaptive cruise control (the sensor that adjusts your carâ&#x20AC;&#x2122;s speed relative to the car in front of you), and navigation indicators. In addition, this HUD will adjust automatically to current weather conditions: on a sunny day or dim overcast conditions, you donâ&#x20AC;&#x2122;t need to adjust the brightness indicator, because the HUD adjusts for ambient light automatically [14].

The HUD is a unique display that overlays information on the outside world view

image source

HUD computer generated image

relay lens assembly

pilot

eyebox

combiner

Safety Starts with Vision

Smart Heads-up Display

4 0 / 41

A longitudinal section of a World War II German C/12A Revi (reflexvisier) reflector gun sight, a non-magnifying optical sight that allows pilot to look through a partially reflecting glass element and see a cross hair reticle superimposed on the field of view.

0mm

100

There are seven factors that interplay in the design of a HUD. It includes

vertical by 6 longitudinal inches. This allows the viewer some freedom

Field of View, Collimation, Eyebox, Boresight, Scaling and Compatibility.

of head movement but movement too far up/down left/right will cause

Field of View indicates the angles, vertically as well as horizontally, subtended at the pilot’s eye, that the combiner displays symbology in relation to the outside view. A narrow FOV means that the view (of

the display to vanish off the edge of the collimator and movement too far back will cause it to crop off around the edge. The pilot is able to view the entire display as long as one of the eyes is inside the eyebox.

a runway, for example) through the combiner might include little addi-

Luminance or contrast have adjustments in luminance and contrast to

tional information beyond the perimeters of the runway environment;

account for ambient lighting, which can vary widely (e.g., from the glare

whereas a wide FOV would allow a ‘broader’ view. For aviation applica-

of bright clouds to moonless night approaches to minimally lit fields).

tions, the major benefit of a wide FOV is that an aircraft approaching the runway in a crosswind might still have the runway in view through the combiner, even though the aircraft is pointed well away from the runway threshold; where a narrow FOV the runway would be ‘off the edge’ of the combiner, out of the HUD’s view. Because the human eyes are separated, each eye receives a different image. The HUD image is viewable by one or both eyes, depending on technical and budget limitations in the design process. Modern expectations are that both eyes view the same image, in other words a “binocular Field of View (FOV)”.

Boresight is very accurately aligned with the aircraft’s three axes – a process called boresighting – so that displayed data conforms to reality typically with an accuracy of ±7.0 milliradians. In this case the word “conform” means, “when an object is projected on the combiner and the actual object is visible, they will be aligned”. This allows the display to show the pilot exactly where the artificial horizon is, as well as the aircraft’s projected path with great accuracy. When Enhanced Vision is used, for example, the display of runway lights are aligned with the actual runway lights when the real lights become visible. Boresighting is

Collimation is collimated which makes the light rays parallel. Because

done during the aircraft’s building process and can also be performed in

the light rays are parallel the lens of the human eye focuses on infinity to

the field on many aircraft.

get a clear image. Collimated images on the HUD combiner are perceived as existing at or near optical infinity. This means that the pilot’s eyes do not need to refocus to view the outside world and the HUD display...the image appears to be “out there”, overlaying the outside world. Eyebox, the optical collimator, produces a cylinder of parallel light so the display can only be viewed while the viewer’s eyes are somewhere within that cylinder, a three-dimensional area called the head motion box or eyebox. Modern HUD eyeboxes are usually about 5 lateral by 3

Scaling is the displayed image. It is scaled to present to the pilot a picture that overlays the outside world in an exact 1:1 relationship. For example, objects (such as a runway threshold) that are 3 degrees below the horizon as viewed from the cockpit must appear at the −3 degree index on the HUD display. Compatibility, HUD components, is designed to be compatible with other avionics and displays[15].

Road Condition

Motortrend_ http://www.thisiscolossal.com/2014/01/severe-skies-the-photography-of-storm-chaser-mike-hollingshead/

Safety Starts with Vision 4 4 / 45

Road Condition

Various road conditions relates to weathers, regions and time. For example, raining in the afternoon results fog on the head-up glasses with a dark situation[16].

In order to resolve this problem, Forward Collision Alert (FCA) is available with radar or front camera. If the vehicle gets into a critical situation where a collision with the preceding vehicle is imminent, FCA warns the driver with a loud alarm as well as a visual warning on the instrument cluster. FCA gives a warning for moving and stationary objects. The driver can adjust the sensitivity of FCA via a control on the steering wheel. If the driver does not react to the visual and audible warnings of FCA, the radar-based Collision Imminent Braking (CIB) takes over and automatically decelerates the vehicle at up to 0.3g to reduce the effects of a collision[17].

Safety Starts with Vision

Road Condition

The new active safety system uses a high-resolution digital camera that looks for shapes of vehicles and lane markings. The system uses audible warnings and a high-mounted visual display to warn the driver if he or she is following another vehicle too closely,

4 6 / 47

The system lights up if you get too close to the car in front and beeps an insistent warning if a collision seems imminent. The same camera provides lane departure warning. As part of the ACC system, dashboard lights tell you brake now! and slow the car so if you donâ&#x20AC;&#x2122;t avoid an accident, the crash speed is lower. Rear-end crashes account for a quarter of all accidents.

In order to operate in varying visibility conditions, the system combines four separate exposures to create each high-resolution image for analysis. For forward collision warning, the camera and image processor add a set of algorithms to identify vehicles ahead and calculate relative speeds. The software looks for vehicle shapes and at night it also looks for tail lamp pairs. Four separate short and long exposures are combined, the short exposures for tail lamps, the long exposures for the vehicle shapes. Photographers call this high dynamic range (HDR) imaging. The shapes are tracked frame-to-frame for size (i.e. distance) changes and a time-to-crash calculation is updated. If the math isnâ&#x20AC;&#x2122;t in your favor, the escalating alerts kick in. In order to operate in varying visibility conditions, the system combines four separate exposures to create each high-resolution image for analysis. This is particularly useful at night when short exposures are needed to get clear images of light sources while long exposures are needed to detect shapes and textures. Night time target recognition is also enhanced by looking for pairs of lights moving together that indicate taillights. The system operates as long as the camera eye is unobstructed, such as by snow or mud.

Fluid_ https://www.flickr.com/photos/appurupai/8416180214/

In addition to searching for other vehicles, the image processor also looks for lane markings to provide lane departure alerts. Available at speeds above 35 mph, the lane departure warning icon shines green when lane markings are detected to indicate the system is active. If the vehicle drifts out of the lane without a turn signal, the lamp switches to flashing amber and is augmented by warning beeps [18].

Safety Starts with Vision

Road Condition

This important safety feature helps reduce wheel spin during acceleration if surfaces youâ&#x20AC;&#x2122;re driving on are slippery. Certain traction control systems combine the ABS speed sensors with the braking system and a Powertrain Control Module to help your vehicle regain traction.

4 8 / 49

ACC system shows off the vehicle’s snow country attributes such as

Cadillac will do with its upcoming XTS sedan, vibrate the seat pan, are the

stability control, all-wheel drive, and winter tires. Forward collision

way to go. GM needs to make a quick but urgent fix here, and follow it by

warning starts at 25 mph and works when the windshield isn’t covered

moving the FCW / LDW cluster into the instrument panel or put it at the

with grime; a flick of the wipers returns functionality to the system.

base of the windshield, as Ford does with its ACC / FCW system, for better

On the dash, there’s a row of warning icons at the top of the center

driver sightlines. Audible alerts for collision warnings are okay because

stack. The icon on the left lights up and glows green when it detects a

you don’t hear them as often and when you do, it’s serious.

car ahead. A larger yellow icon lights up when you’re too close. When a collision seems likely, the yellow icon flashes, a chime beeps seven times, and the brakes are pre-charged for maximum force once you decide you will stop the car. ACC system’s forward collision warning is simple, idiot-proof, and it works.

According to GMC, there’s other useful tech in the GMC Terrain, which is the upmarket cousin to the Chevrolet Equinox and styled with what GMC calls “tailored toughness.” GMC added some useful standard tech features with the current model, starting with a 7-inch color LCD with touchscreen interface, a rear camera, USB adapter, and Bluetooth.

ACC system helps you stay on course by detecting the difference

Later in the 2012 model year, GMC adds Intellilink, its take on Ford Sync’s

between the steering wheel angle and the direction the vehicle is actu-

interface that can control a smartphone; Pandora streaming audio; and

ally turning. The system “reads” the steering wheel position, the amount

Stitcher on-demand web radio. GMC in 2012 will also offer, across the

of sideways force in play, the speed of the vehicle and the vehicle’s

Terrain line, the must-have forward collision warning / lane departure

response to steering wheel input. It then uses the brakes and, if neces-

warning feature; right now it’s limited to the most costly Terrain model

sary, adjusts engine torque to help you keep your vehicle on track.

with a V6 engine. The Terrain is fine as a highway car (upscale cockpit,

The simpler lane departure warning system is less admirable because the alerts comprise an amber center stack warning icon (okay) and a three-beep warning chime (ill-informed). It works at 35 mph and up. GM engineers weren’t paying attention when other automakers built their LDW systems. You don’t need to be a human factors Ph.D to know a chime or beep tells the passengers, “The driver screwed up,” and the driver is likely to respond by disabling the system. Lane departure warning (and blind spot detection) systems that lightly vibrate the steering wheel or, as

good sound insulation). It’s excellent on snow and ice because of its stability control system and dedicated winter tires (on my Terrain) that make sense if you live in snow country [19].

Conclusion

5 2 / 53

Intelligent Transport Systems (ITS) have great potential to save time, to save money, to save lives, and to improve our environment. ITSâ&#x20AC;&#x2122;s have considerable potential to be a future commercial success. These systems are also closely linked to other major emerging technologies; the Internet, mobile data services, smart sensors, artificial intelligence, position technologies, geographical information systems (GIS)[20]. Motortrend_ http://www.thisiscolossal.com/2014f-storm-chaser-mike-hollingshead/

Safety Starts with Vision

Road and traffic sign recognition is one of the important fields in the ITS. This is due to the importance of the road signs and traffic signals in daily life. They define a visual language that can be interpreted by the drivers. They represent the current traffic situation on the road, show the danger and difficulties around the drivers, give warnings to them, and help them with their navigation by providing useful information that makes the driving safe and convenient [21].

Reference

01 http://www.mobileye.com/technology/applications/traffic-sign-detection/ 02

MAZINAN, A, and M SARIKHANI. “Providing An Efficient Intelligent Transportation

System Through Detection, Tracking And Recognition Of The Region Of Interest In Traf

fic Signs By Using Non-Linear SVM Classifier In Line With Histogram Oriented Gradient

And Kalman Filter Approach.” Sadhana 39.1 (2014): 27-37. Academic Search Premier.

Web. 27 Apr. 2014.

Bond, Amy R. F., and Darryl N. Jones. “Wildlife Warning Signs: Public Assessment Of

Components, Placement And Designs To Optimise Driver Response.” Animals (2076-

2615) 3.4 (2013): 1142-1161. Academic Search Premier. Web. 27 Apr. 2014.

Zaklouta, Fatin, and Bogdan Stanciulescu. “Real-Time Traffic Sign Recognition In Three

Stages.” Robotics & Autonomous Systems 62.1 (2014): 16-24. Academic Search Premier.

Web. 27 Apr. 2014.

05 https://sites.google.com/site/mcvibot2011sep/home 06 http://www.usa-traffic-signs.com/Test_s/50.htm 07

Timofte, Radu, Karel Zimmermann, and Luc Van Gool. “Multi-View Traffic Sign

Detection, Recognition, And 3D Localisation.” Machine Vision & Applications 25.3 (2014):

633-647. Academic Search Premier. Web. 27 Apr. 2014.

Overett, Gary, et al. “Creating Robust High-Throughput Traffic Sign Detectors Using

Centre-Surround HOG Statistics.” Machine Vision & Applications 25.3 (2014): 713-726.

Academic Search Premier. Web. 27 Apr. 2014.

Peschke, Claudia, Bettina Olk, and Claus C. Hilgetag. “Should I Stay Or Should I Go –

Cognitive Conflict In Multi-Attribute Signals Probed With East And West German

‘Ampelmännchen’ Traffic Signs.” Plos ONE 8.5 (2013): 1-5. Academic Search Premier.

Web. 27 Apr. 2014.

10 http://www.cnbc.com/id/101548440

11 https://www.abiresearch.com/market-research/product/1006361-lane-departure- warning-and-road-sign-recog/

Sun, Zhan-Li, et al. “Application Of BW-ELM Model On Traffic Sign Recognition.” Neuro

computing 128.(2014): 153-159. Academic Search Premier. Web. 27 Apr. 2014.

Coronado, Gustavo A. Peláez, et al. “Detection And Classification Of Road Signs For

Automatic Inventory Systems Using Computer Vision.” Integrated Computer-Aided

Engineering 19.3 (2012): 285-298. Academic Search Premier. Web. 27 Apr. 2014.

Hu, Zhaozheng. “Intelligent Road Sign Inventory (IRSI) With Image Recognition And

Attribute Computation From Video Log.” Computer-Aided Civil & Infrastructure Engi

neering 28.2 (2013): 130-145. Academic Search Premier. Web. 27 Apr. 2014.

Yang, Xing. “Enhancement For Road Sign Images And Its Performance Evaluation.”

Optik - International Journal For Light & Electron Optics 124.14 (2013): 1957-1960. Aca

demic Search Premier. Web. 27 Apr. 2014.

Park, Jung-Guk, and Kyung-Joong Kim. “Design Of A Visual Perception Model With

Edge-Adaptive Gabor Filter And Support Vector Machine For Traffic Sign Detection.”

Expert Systems With Applications 40.9 (2013): 3679-3687. Academic Search Premier.

Web. 27 Apr. 2014.

Xue, Yuan, et al. “Traffic Sign Recognition Based On A Context-Aware Scale-Invariant

Feature Transform Approach.” Journal Of Electronic Imaging 22.4 (2013): 1-16. Academic

Search Premier. Web. 27 Apr. 2014.

18 http://www.dailytech.com/Siemens+Announces+Traffic+Sign+Recognition+Technol ogy/article4550.htm

19 http://www.springerreference.com/docs/html/chapterdbid/318384.html 20 http://www.nvidia.com/object/advanced-driver-assistance-systems.html 21 http://www.wired.com/2008/06/have-that-latte/