Google driverless car documentation pdf


 

DRIVERLESS CAR DOCUMENTATION - Download as Word Doc .doc), PDF File .pdf), Download as DOC, PDF, TXT or read online from Scribd . harmful to people.1 VAHICLES FOR SURFACED ROADS Google driverless car. or itself . Driverless Car Documentation - Download as Word Doc .doc), PDF File .pdf), Text property.1 VAHICLES FOR SURFACED ROADS Google driverless car. While initial reports indicate that the Google Car driverless automobile will be more safe and efficient than current vehicles, the Google Car is not without its.

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Google Driverless Car Documentation Pdf

The Google Driverless Car is like any car, but: ➢ It can steer itself while looking out for obstacles. ➢ It can accelerate itself to the correct speed. Autonomous car, seminar reports ppt pdf doc presentation seminar report,pdf Robotic car seminar report. document. driverless car documentation. document. The focus on 'driverless' cars is on what they lack – a driver. Often this misses what they Toyota vehicles, and Google's own prototype. Trials of driverless cars.

Pawan Janorkar 01 July From the invention of the car there is a great relation between human and car. Because by the invention of the car the automobile industry was established, by this car the traveling time from one place to another place is reduced. The car brings royalty from the invention. Google Driverless Car in these the Google puts the technology in the car, that technology was Artificial Intelligence with Google map view. The input video camera was fixed beside the front mirror inside the car, A LIDAR sensor was fixed on the top of the vehicle, RADAR sensor on the front of the vehicle and a position sensor attached to one of the rear wheels that helps locate the cars position on the map, The Computer, Router, Switch, Fan, Inverter, rear Monitor, Topcon, Velodyne, Applanix and Battery are kept inside the car. The system combines information gathered from Google street view with artificial intelligence software that combines input from video camera inside the car, a LIDAR sensor on the top of the vehicle, RADAR sensors on the front of the vehicle and a position sensor attached to one of the rear wheel that helps to locate the car position on the map.

This mobility is usually taken for granted by most people and they realize that transportation forms the basis of our civilization. The need for a more efficient, balanced and safer transportation system is obvious. This need can be best met by the implementation of autonomous transportation systems.

In the future, automated system will help to avoid accidents and reduce congestion. The future vehicles will be capable of determining the best route and warn each other about the conditions a head. Many companies and institutions working together in countless projects in order to implement the intelligent vehicles and transportation networks of the future.

Some believe that autonomous vehicles have the potential to transform the transportation industry while virtually eliminating accidents, and cleaning up the environment.

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According to urban designer and futurist Michael E. Arth, driverless electric vehicles—in conjunction with the increased use of virtual reality for work, travel, and pleasure— could reduce the world's ,, vehicles to a fraction of that number within a few decades. This would also allow for getting the appropriate vehicle for the particular need —a bus could come for a group of people, a limousine could come for a special night out, and a Segway could come for a short trip down the street for one person.

Children could be chauffeured in supervised safety, DUIs would no longer exist, and 41, lives could be saved each year in the U. For the wider application of artificial intelligence to automobiles see smart cars. The control mechanism of an autonomous car consists of three main blocks as shown below. The advantage of using stock cars is the ease of obtaining the car through sponsors.

The stocks cars help convey the message autonomous vehicles are not science fiction anymore and these systems can be implemented on normal cars. An early representation of the driverless car was Norman Bel Geddes's Futurama exhibit sponsored by General Motors at the World's Fair, which depicted electric cars powered by circuits embedded in the roadway and controlled by radio.

The history of autonomous vehicles starts in with the Tsukuba Mechanical Engineering Lab in Japan. They demonstrated autonomous driving in free lanes, convoy driving, and lane changes left and right with autonomous passing of other cars.

Again it drove in traffic, executing manoeuvres to pass other cars. Despite being a research system without emphasis on long distance reliability, it drove up to km without human intervention. In , the Carnegie Mellon University Navlab project achieved This car, however, was semiautonomous by nature: The vehicle had only two black-and-white low-cost video cameras on board, and used stereoscopic vision algorithms to understand its environment, as opposed to the "laser, radar - whatever you need" approach taken by other efforts in the field.

Demo III demonstrated the ability of unmanned ground vehicles to navigate miles of difficult off-road terrain, avoiding obstacles such as rocks and trees. Not only were individual vehicles controlled e.

The and DARPA competitions allowed international teams to compete in fully autonomous vehicle races over rough unpaved terrain and in a non-populated suburban setting.

In , General Motors stated that they will begin testing driverless cars by , and they could be on the road by The four driverless electric vans successfully ended the drive from Italy to China via the arriving at the Shanghai Expo on 28 October. In order to better utilize road-space. The final goal of safe door-to-door transportation in arbitrary environments is not yet reached though. Many kinds of robots have some degree of autonomy. Autonomous robots are robots that can perform desired tasks in unstructured environments without continuous human guidance.

It may not be that every degree of freedom exists in their surrounding environment. Some modern factory robots are "autonomous" within the strict confines of their direct environment. Fully autonomous vehicle Various enhancements to the infrastructure either an entire area.

All other vehicles simply follow the lead of the first vehicle. Different robots can be autonomous in different ways. A high degree of autonomy is particularly desirable in fields such as space exploration. The exact orientation and position of the next object of work and in the more advanced factories even the type of object and the required task must be determined. This can vary unpredictably at least from the robot's point of view.

This is the longest-ever trip by an unmanned vehicle. Page 7. One important area of robotics research is to enable the robot to cope with its environment whether this be on land.

An autonomous robot may also learn or gain new capabilities like adjusting strategies for accomplishing its task s or adapting to changing surroundings. Not one of the 25 entrants completed the course. This system is based around the MicroAutoBox from dSpace. In March Technical University Braunschweig. The car was designed by Burkhard Huhnke of Volkswagen Research. Page 8. Argo was developed in and demonstrated to the world in Some of these projects are military-oriented.

Two projects. Stanford Racing Team. Some of the systems on display could be ordered and implemented immediately. The event included various military automated and remotely-operated robots. Victor Tango. Tartan Racing. In August a civilian version of the event was held in Switzerland. Such systems already function in many airports. This idea is also known a Dual mode transit.

Groups working on this concept are: The technologies are proven. The idea is that privately-owned cars would be built with the ability to dock themselves onto a public monorail system.

See also Personal rapid transit for another concept along those lines. When leaving the system each car verifies that its driver is Page Dual-mode transit seeks to address a similar audience as personal rapid transit. The term is also used variously to describe the beam of the system. Examples of this concept include the TriTrack.

The transportation system is often referred to as a railway. In fact. Dual mode transit describes transportation systems in which vehicles operate on both public roads and on a guideway. In a typical dual mode transit system.

DRIVERLESS CAR DOCUMENTATION

AHS allows specially equipped cars to join the system using special 'acceleration lanes' and to leave through 'deceleration lanes'. The term originates from the contraction of the words mono one and rail. Like the dual-mode monorail. As of Page Platoons decrease the distances between cars using electronic. This concerted effort by the US government seems to have been pretty much abandoned because of social and political forces.

Grouping vehicles into platoons is a method of increasing the capacity of roads. This system also allows for a closer headway between vehicles by eliminating reacting distance needed for human reaction. The event generated much press coverage. The test site is a kilometer. The system is being designed by Swoop Technology. This capability would allow many cars to accelerate or brake simultaneously.

The vehicles will still have drivers since they need to enter and exit the special lanes. Instead of waiting after a traffic light changes to green for drivers ahead to react.

The intention is to allow the vehicles to travel at shorter following distances and thereby allow more vehicles to use the lanes. An automated highway system is a proposed technology for doing this. Some implementations use radar to avoid collisions and coordinate speed.

The cars avoid collisions with obstacles located in the environment using laser long range and ultra-sonic short-range sensors. The company's purpose-built electric vehicles locate themselves using odometry readings. The FROG system is deployed for industrial purposes in factory sites. The system has been applied both indoors and outdoors. Drivers would probably need a special license endorsement on account of the new skills required and the added responsibility when driving in the lead.

The company also has no intention of developing such technology at this time. The supervisory system merely administers the operations and directs traffic where required. The vehicles are completely autonomous and plan their own routes from A to B.

The technology consists of a combination of autonomous vehicles and a supervisory central system. Smart cars with artificial intelligence could automatically join and leave platoons. At this time the system is not suited yet for running the sheer number of vehicles encountered in urban settings. This system experienced an accident that proved to be caused by a Human error.

The automated highway system is a proposal for one such system. Driver-assistance mechanisms are of several distinct types. Roadway with lane markings In road-transport terminology. There are two main types of systems: Many of the technologies detailed below will probably serve as components of any future driverless car — meanwhile they are being marketed as gadgets that assist human drivers in one way or another.

These systems are designed to minimize accidents by addressing the main causes of collisions: In the NHTSA began studying whether to mandate lane departure warning systems and frontal collision warning systems on automobiles. This approach is slowly trickling into standard cars e. A blind spot in a vehicle are areas around the vehicle that cannot be directly observed under existing circumstances.

The first production lane departure warning system in Europe was developed by the United States's Iteris Company for Mercedes Actros commercial trucks. Blind spots exist in a wide range of vehicles: No warnings are generated if. The system debuted in and is now available on most trucks sold in Europe In The blue car's driver sees the green car through his mirrors but cannot see the red car without turning to check his blind spot. In all of these systems.

LDW if the vehicle is leaving its lane. A long-range radar antenna. The most common are the rear quarter blind spots. Some of these make the use of radar altimeters possible. Vehicles in the adjacent lanes of the road that fall into these blind spots may not be visible using only the car's mirrors. Radar signals are reflected especially well by materials of considerable electrical conductivity—especially by most metals.

The radar signals that are Page The radar dish. Other areas that are sometimes called blind spots are those that are too low to see behind. Radar is an object-detection system which uses electromagnetic waves — specifically radio waves — to determine the range.

Rear quarter blind spots can be: A radar system has a transmitter that emits radio waves called radar signals in predetermined directions. The object returns a tiny part of the wave's energy to a dish or antenna which is usually located at the same site as the transmitter.

Detection of vehicles or other objects in such blind spots are aided by systems such as video cameras or distance sensors. Further in the future. It also seems possible for traffic lights. Wireless units will be installed in vehicles and probably also in fixed locations such as near traffic signals and emergency call boxes along the road. It is an electronic sub-system in a car or other vehicle for the purpose of exchanging safety information.

Sensors in the cars and at the fixed locations. If the object is moving either closer or farther away. This may involve temporary ad hoc wireless local area networks. The range of the radio links can be extended by forwarding messages along multi-hop paths. Humans have poor night vision compared to many animals. Even without fixed units. Wireless vehicle safety communications telematics aid in car safety and road safety. There are also possibilities that need less engineering effort.

Whether by biological or technological means. When any column member slows down. Cars and trucks with the wireless system connected to their brakes may move in convoys. There are basically three types of sensors used in motion detectors spectrum: Passive infrared sensor PIR Looks for body heat.

Although the human visual system can. This can be achieved by measuring optical or acoustical changes in the field of view. Human vision is confined to a small portion of the electromagnetic spectrum called visible light. Ultrasonic active Page Sufficient intensity range is simply the ability to see with very small quantities of light. An electronic motion detector contains a motion sensor that transforms the detection of motion into an electric signal.

Night-useful spectral range techniques can sense radiation that is invisible to a human observer. Most motion detectors can detect up to 15—25 meters 50—80 feet. They form a vital component of comprehensive security systems.

Driverless Car Documentation

No energy is emitted from the sensor. Enhanced spectral range allows the viewer to take advantage of non-visible sources of electromagnetic radiation such as near-infrared or ultraviolet radiation. Enhanced intensity range is achieved via technological means through the use of an image intensifier.

A motion detector is a device that contains a physical mechanism or electronic sensor that quantifies motion that can be either integrated with or connected to other devices that alert the user of the presence of a moving object within the field of view.

It compares the driver's intended direction determined through the measured steering wheel angle to the vehicle's actual direction determined through measured lateral acceleration. Similar to a police radar gun. These systems modify the driver's instructions so as to execute them in a more effective way. Electronic Stability Control ESC is a computerized technology that improves safety through a vehicle's stability by detecting and minimizing skids.

Braking is automatically applied to individual wheel. Microwave active Sensor sends out microwave pulses and measures the reflection off a moving object. This system is based around the MicroAutoBox from dSpace. This, as it was intended to test VW hardware without a human driver for consistent test results. The car was designed by Burkhard Huhnke of Volkswagen Research.

There are four clusters of activity relating to free-ranging off-road cars. Some of these projects are military-oriented. Not one of the 25 entrants completed the course. The event included various military automated and remotely-operated robots, for various military uses.

Some of the systems on display could be ordered and implemented immediately. In August a civilian version of the event was held in Switzerland.

As a followup from its success with Unmanned Combat Air Vehicles, and following the construction of the Israeli West Bank Barrier there has been significant interest in developing a fully automated border-patrol vehicle.

Two projects, by Elbit Systems and Israel Aircraft Industries are both based on the locally-produced Armored "Tomcar" and have the specific purpose of patrolling barrier fences against intrusions. The following projects were conceived as practical attempts to use available technology in an incremental manner to solve specific problems, like transport within a defined campus area, or driving along a stretch of motorway. The technologies are proven, and the main barrier to widespread implementation is the cost of deploying the infrastructure.

Such systems already function in many airports, on railroads, and in some European towns. There is a family of projects, all currently still at the experimental stage, that would combine the flexibility of a private automobile with the benefits of a monorail system. The idea is that privately-owned cars would be built with the ability to dock themselves onto a public monorail system, where they become part of a centrally managed, fully computerized transport system— more akin to a driverless train system as already found in airports than to a driverless car.

This idea is also known a Dual mode transit. See also Personal rapid transit for another concept along those lines, for purely public transport. The term is also used variously to describe the beam of the system, or the vehicles traveling on such a beam or track. The transportation system is often referred to as a railway. Colloquially, the term "monorail" is often used erroneously to describe any form of elevated rail or peoplemover.

In fact, the term solely refers to the style of track, not its elevation. Dual mode transit describes transportation systems in which vehicles operate on both public roads and on a guideway; thus using two modes of transport. In a typical dual mode transit system, private vehicles comparable to automobiles would be able to travel under driver control on the street, but then enter a guideway, which may be a specialized form of Railway or monorail, for automated travel for an extended distance. Dual-mode transit seeks to address a similar audience as personal rapid transit.

Automated highway systems AHS are an effort to construct special lanes on existing highways that would be equipped with magnets or other infrastructure to allow vehicles to stay in the center of the lane, while communicating with other vehicles and with a central system to avoid collision and manage traffic.

Like the dual-mode monorail, the idea is that cars remain private and independent, and just use the AHS system as a quick way to move along designated routes.

AHS allows specially equipped cars to join the system using special 'acceleration lanes' and to leave through 'deceleration lanes'. When leaving the system each car verifies that its driver is. The test site is a kilometer, high-occupancy-vehicle HOV segment of Interstate 15, 16 kilometers north of downtown San Diego.

The event generated much press coverage. This concerted effort by the US government seems to have been pretty much abandoned because of social and political forces, above all else the desire to create a less futuristic and more marketable solution. As of , a three-year project is underway to allow robot controlled vehicles, including buses and trucks, to use a special lane along 20 Interstate The intention is to allow the vehicles to travel at shorter following distances and thereby allow more vehicles to use the lanes.

The vehicles will still have drivers since they need to enter and exit the special lanes. Grouping vehicles into platoons is a method of increasing the capacity of roads. An automated highway system is a proposed technology for doing this. Platoons decrease the distances between cars using electronic, and possibly mechanical, coupling. This capability would allow many cars to accelerate or brake simultaneously. Instead of waiting after a traffic light changes to green for drivers ahead to react, a synchronized platoon would move as one, allowing up to a fivefold increase in traffic throughput if spacing is diminished that much.

This system also allows for a closer headway between vehicles by eliminating reacting distance needed for human reaction. Drivers would probably need a special license endorsement on account of the new skills required and the added responsibility when driving in the lead.

Smart cars with artificial intelligence could automatically join and leave platoons. The automated highway system is a proposal for one such system, where cars organise themselves into platoons of eight to twenty-five. The technology consists of a combination of autonomous vehicles and a supervisory central system. The company's purpose-built electric vehicles locate themselves using odometry readings, recalibrating themselves occasionally using a "maze" of magnets embedded in the environment, and GPS.

The cars avoid collisions with obstacles located in the environment using laser long range and ultra-sonic short-range sensors. The vehicles are completely autonomous and plan their own routes from A to B.

The supervisory system merely administers the operations and directs traffic where required. At this time the system is not suited yet for running the sheer number of vehicles encountered in urban settings.

The company also has no intention of developing such technology at this time. The FROG system is deployed for industrial purposes in factory sites, and is marketed as a pilot public transport system in the city of Capelle aan den IJssel by its subsidiary 2getthere.

This system experienced an accident that proved to be caused by a Human error. Many of the technologies detailed below will probably serve as components of any future driverless car — meanwhile they are being marketed as gadgets that assist human drivers in one way or another.

This approach is slowly trickling into standard cars e. Driver-assistance mechanisms are of several distinct types, sensorial-informative, actuation- corrective, and systemic. In road-transport terminology, a lane departure warning system is a mechanism designed to warn a driver when the vehicle begins to move out of its lane unless a turn signal is on in that direction on freeways and arterial roads. These systems are designed to minimize accidents by addressing the main causes of collisions: In the NHTSA began studying whether to mandate lane departure warning systems and frontal collision warning systems on automobiles.

The first production lane departure warning system in Europe was developed by the United States's Iteris Company for Mercedes Actros commercial trucks. The system debuted in and is now available on most trucks sold in Europe. In all of these systems, the driver is warned of unintentional lane departures by an audible rumble strip sound generated on the side of the vehicle drifting out of the lane. No warnings are generated if, before crossing the lane, an active turn signal is given by the driver.

A blind spot in a vehicle are areas around the vehicle that cannot be directly observed under existing circumstances. Blind spots exist in a wide range of vehicles: The blue car's driver sees the green car through his mirrors but cannot see the red car without turning to check his blind spot. The most common are the rear quarter blind spots, areas towards the rear of the vehicle on both sides. Vehicles in the adjacent lanes of the road that fall into these blind spots may not be visible using only the car's mirrors.

Rear quarter blind spots can be:. Other areas that are sometimes called blind spots are those that are too low to see behind, in front, or to the sides of a vehicle, especially those with a high seating position, such as vans, trucks, and SUVs. Detection of vehicles or other objects in such blind spots are aided by systems such as video cameras or distance sensors, though these remain uncommon or expensive options in general-purpose automobiles.

Radar is an object-detection system which uses electromagnetic waves — specifically radio waves — to determine the range, altitude, direction, or speed of both moving and fixed objects such as aircraft, ships, spacecraft, guided missiles, motor vehicles, weather formations, and terrain. The radar dish, or antenna, transmits pulses of radio waves or microwaves which bounce off any object in their path. The object returns a tiny part of the wave's energy to a dish or antenna which is usually located at the same site as the transmitter.

A radar system has a transmitter that emits radio waves called radar signals in predetermined directions. Radar signals are reflected especially well by materials of considerable electrical conductivity—especially by most metals, by seawater, by wet land, and by wetlands. Some of these make the use of radar altimeters possible. The radar signals that are. If the object is moving either closer or farther away, there is a slight change in the frequency of the radio waves, due to the Doppler Effect.

Wireless vehicle safety communications telematics aid in car safety and road safety. It is an electronic sub-system in a car or other vehicle for the purpose of exchanging safety information, about such things as road hazards and the locations and speeds of vehicles, over short range radio links. This may involve temporary ad hoc wireless local area networks.

Wireless units will be installed in vehicles and probably also in fixed locations such as near traffic signals and emergency call boxes along the road. Sensors in the cars and at the fixed locations, as well as possible connections to wider networks, will provide the information, which will be displayed to the drivers in some way.

The range of the radio links can be extended by forwarding messages along multi-hop paths. Even without fixed units, information about fixed hazards can be maintained by moving vehicles by passing it backwards. It also seems possible for traffic lights, which one can expect to become smarter, to use this information to reduce the chance of collisions. Further in the future, it may connect directly to the adaptive cruise control or other vehicle control aids.

Cars and trucks with the wireless system connected to their brakes may move in convoys, to save fuel and space on the roads. When any column member slows down, all those behind it will automatically slow also. There are also possibilities that need less engineering effort. Night vision is the ability to see in a dark environment. Whether by biological or technological means, night vision is made possible by a combination of two approaches: Humans have poor night vision compared to many animals, in part because the human eye lacks a tapetum lucidum.

Night-useful spectral range techniques can sense radiation that is invisible to a human observer. Human vision is confined to a small portion of the electromagnetic spectrum called visible light.

Enhanced spectral range allows the viewer to take advantage of non-visible sources of electromagnetic radiation such as near-infrared or ultraviolet radiation. Sufficient intensity range is simply the ability to see with very small quantities of light. Although the human visual system can, in theory, detect single photons under ideal conditions, the neurological noise filters limit sensitivity to a few tens of photons, even in ideal conditions.

Enhanced intensity range is achieved via technological means through the use of an image intensifier, gain multiplication CCD, or other very low-noise and high-sensitivity array of photodetectors. A motion detector is a device that contains a physical mechanism or electronic sensor that quantifies motion that can be either integrated with or connected to other devices that alert the user of the presence of a moving object within the field of view.

They form a vital component of comprehensive security systems, for both homes and businesses. An electronic motion detector contains a motion sensor that transforms the detection of motion into an electric signal.

This can be achieved by measuring optical or acoustical changes in the field of view. Most motion detectors can detect up to 15—25 meters 50—80 feet. Passive infrared sensor PIR Looks for body heat. No energy is emitted from the sensor.

Ultrasonic active. Microwave active Sensor sends out microwave pulses and measures the reflection off a moving object. Similar to a police radar gun. Electronic Stability Control ESC is a computerized technology that improves safety through a vehicle's stability by detecting and minimizing skids.

When ESC detects loss of steering control, it automatically applies the brakes to help "steer" the vehicle where the driver intends to go. Braking is automatically applied to individual wheel, such as the outer front wheel to counter oversteer or the inner rear wheel to counter understeer.

Some ESC systems also reduce engine power until control is regained. ESC does not improve a vehicle's cornering performance; instead, it helps to minimize the loss of control.

During normal driving, ESC works in the background and continuously monitors steering and vehicle direction. It compares the driver's intended direction determined through the measured steering wheel angle to the vehicle's actual direction determined through measured lateral acceleration, vehicle rotation yaw , and individual road wheel speeds.

ESC intervenes only when it detects loss of steering control, i. This may happen, for example, when skidding during emergency evasive swerves, understeer or oversteer during poorly judged turns on slippery roads, or hydroplaning.

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ESC estimates the direction of the skid, and then applies the brakes to individual wheels asymmetrically in order to create torque about the vehicle's vertical axis, opposing the skid and bringing the vehicle back in line with the driver's commanded direction.

Additionally, the system may reduce engine power or operate the transmission to slow the vehicle down. These systems modify the driver's instructions so as to execute them in a more effective way, for example the most widely deployed system of this type is ABS; conversely power steering is not a control mechanism, but just a convenience - it is not involved in decision making. This shortens stopping distances in most cases and, more importantly, allows the driver to steer the vehicle while braking.

Distributing power to all four wheels lessens the chances of wheel spin. It also suffers less from oversteer and understeer. Uses various sensors to intervene when the car senses a possible loss of control. The car's control unit can reduce power from the engine and even apply the brakes on individual wheels to prevent the car from understeering or oversteering.

An anti-lock braking system ABS is a safety system that allows the wheels on a motor vehicle to continue interacting tractively with the road surface as directed by driver steering inputs while braking, preventing the wheels from locking up that is, ceasing rotation and therefore avoiding skidding.

An ABS generally offers improved vehicle control and decreases stopping distances on dry and slippery surfaces for many drivers; however, on loose surfaces like gravel or snow-covered pavement, an ABS can significantly increase braking distance, although still improving vehicle control. Since initial widespread use in production cars, anti-lock braking systems have evolved considerably. Recent versions not only prevent wheel lock under braking, but also electronically control the front-to-rear brake bias.

This function, depending on its specific capabilities and implementation, is known as electronic brakeforce distribution EBD , traction control system, emergency brake assist, or electronic stability control ESC.

The ABS was first developed for aircraft use in by the French automobile and aircraft pioneer, Gabriel Voisin, as threshold braking on airplanes is nearly impossible. An early system was Dunlop's Maxaret system, which was introduced in the s and is still in use on some aircraft models. These systems use a flywheel and valve attached to a hydraulic line that feeds the brake cylinders. The flywheel is attached to a drum that runs at the same speed as the wheel.

In normal braking, the drum and flywheel should spin at the same speed. Chrysler, together with the Bendix Corporation, introduced a computerized, three-channel, four- sensor all-wheel ABS called "Sure Brake" for its Imperial. It was available for several years thereafter, functioned as intended, and proved reliable.

A typical ABS includes a central electronic control unit ECU , four wheel speed sensors, and at least two hydraulic valves within the brake hydraulics. The ECU constantly monitors the rotational speed of each wheel; if it detects a wheel rotating significantly slower than the others, a condition indicative of impending wheel lock, it actuates the valves to reduce hydraulic pressure to the brake at the affected wheel, thus reducing the braking force on that wheel; the wheel then turns faster.

Conversely, if the ECU detects a wheel turning significantly faster than. This process is repeated continuously and can be detected by the driver via brake pedal pulsation. Some anti-lock system can apply or release braking pressure 16 times per second. The ECU is programmed to disregard differences in wheel rotative speed below a critical threshold, because when the car is turning, the two wheels towards the center of the curve turn slower than the outer two. For this same reason, a differential is used in virtually all roadgoing vehicles.

If a fault develops in any part of the ABS, a warning light will usually be illuminated on the vehicle instrument panel, and the ABS will be disabled until the fault is rectified. The modern ABS applies individual brake pressure to all four wheels through a control system of hub-mounted sensors and a dedicated micro-controller. ABS is offered or comes standard on most road vehicles produced today and is the foundation for ESC systems, which are rapidly increasing in popularity due to the vast reduction in price of vehicle electronics over the years.

Here, a minimum of two additional sensors are added to help the system work: The theory of operation is simple: The steering wheel sensor also helps in the operation of Cornering Brake Control CBC , since this will tell the ABS that wheels on the inside of the curve should brake more than wheels on the outside, and by how much. If, when accelerating, the tire loses traction, the ABS controller can detect the situation and take suitable action so that traction is regained.

Manufacturers often offer this as a separately priced option even though the infrastructure is. More sophisticated versions of this can also control throttle levels and brakes simultaneously. Electronic brakeforce distribution EBD or EBFD , Electronic brakeforce limitation EBL or Electronic brake assist EBA is an automobile brake technology that automatically varies the amount of force applied to each of a vehicle's brakes, based on road conditions, speed, loading, etc.

Always coupled with anti-lock braking systems, EBD can apply more or less braking pressure to each wheel in order to maximize stopping power whilst maintaining vehicular control. Typically, the front end carries the most weight and EBD distributes less braking pressure to the rear brakes so the rear brakes do not lock up and cause a skid. In some systems, EBD distributes more braking pressure at the rear brakes during initial brake application before the effects of weight transfer become apparent.

The job of the EBD as a subsystem of the ABS system is to control the effective adhesion utilization by the rear wheels. The pressure of the rear wheels is approximated to the ideal brake force distribution in a partial braking operation.

To do so, the conventional brake design is modified in the direction of rear axle overbraking, and the components of the ABS are used. EBD reduces the strain on the hydraulic brake force proportioning valve in the vehicle. EBD optimizes the brake design with regard to: A micro- computer then monitors the actual speed of the vehicle using data from velocity sensors. The actual speed is compared to the desired speed and the controller adjusts the throttle as necessary.

A completely autonomous vehicle is one in which a computer performs all the tasks that the human driver normally would. Ultimately, this would mean get- ting in a car, entering the destination into a computer, and enabling the system. From there, the car would take over and drive to the destination with no human input. The car would be able to sense its environment and make steering and speed changes as necessary. This scenario would require all of the automotive technologies mentioned above: lane detection to aid in passing slower vehicles or exiting a highway; obstacle detection to locate other cars, pedestrians, animals, etc.

In addition, sensors would be needed to alert the car to road or weather con- ditions to ensure safe traveling speeds. For example, the car would need to slow down in snowy or icy conditions. We perform many tasks while driving without even thinking about it.

Completely automating the car is a challenging task and is a long way off. However, advances have been made in the individual systems. As of , Google has tested several vehicles equipped with the system, driving , miles , km without any human intervention, the only accident occurring when one of the cars was rear-ended while stopped at a red light.

Google anticipates that the increased accuracy of its automated driving system could help reduce the number of traffic-related injuries and deaths, while using energy and space on roadways more efficiently. The problem is winning the trust of the people to allow a computer to drive a vehicle for them, because of this, there must be research and testing done over and over again to assure a near fool proof final product.

The product will not be accepted instantly, but over time as the systems become more widely used people will realize the benefits of it. It includes sensor section, processor section and drive by wire technology.

There are two processors; one is for the general working and one for handling the sensory inputs which is real time. Acceler- ator is directly controlled by the general purpose processor. The sensory inputs include inputs from the lidar, radar, position estimator and street view images.

Lidar creates a 3-D images platform for mounting the obstacles and map. The camera visuals are used for detecting the colour of the traffic signal based on which the vehicle moves on the road. The general purpose processor is constantly communicating with the engine control unit. The modern uses of radar are highly diverse, including air traffic control, radar astronomy, air-defense systems, antimissile systems; nautical radars to locate landmarks and other ships; aircraft anti collision systems; ocean- surveillance systems, outer-space surveillance and rendezvous systems; meteorolog- ical precipitation monitoring; altimetry and flight-control systems; guided-missile target-locating systems; and ground-penetrating radar for geological observations.

A radar system has a transmitter that emits radio waves called radar signals inpredetermined directions. Radar signals are reflected especially well by materials of considerable electrical conductivity- especially by most metals, by seawater, by wet land, and by wetlands.

Some of these make the use of radar altimeters possible. The radar signals that are reflected back towards the transmitter are the desirable ones that make radar work. If the object is moving either closer or farther away, there is a slight change in the frequency of the radio waves, due to the Doppler effect.

Radar receivers are usually, but not always, in the same location as the trans- mitter. Although the reflected radar signals captured by the receiving antenna are usually very weak, these signals can be strengthened by the electronic amplifiers that all radar sets contain. More sophisticated methods of signal processing are also nearly always used in order to recover useful radar signals.

The weak absorption of radio waves by the medium through which it passes is what enables radar sets to detect objects at relatively-long ranges at which other electromagnetic wavelengths, such as visible light, infrared light, and ultraviolet light, are too strongly attenuated. Such things as fog, clouds, rain, falling snow, and sleet that block visible light are usually transparent to radio waves.

Certain, specific radio frequencies that are absorbed or scattered by water vapor, raindrops, or atmospheric gases especially oxygen are avoided in designing radars except when detection of these is intended. This process of directing artificial radio waves towards objects is called illumination, regardless of the fact that radio waves are completely invisible to the human eye or cameras.

High tech radar systems are associated with digital signal processing and are capable of extracting objects from very high noise levels Figure3. Parking assistance can be provided by rear mounted sensors with 1. Sensors with ability to scan out up to 30 mprovide warning of imminent collision so airbags can be armed and seat restraints pretension.

A narrow laserbeam can be used to map physical features with very high resolution. LIDAR has been used extensively for atmospheric research and meteorology. Advanced Research Lidar. Wavelengths in a range from about 10 micrometers to the UV ca. Typically light is reflected via back scattering. Laser nm lasers are most common for non-scientific applications. They are inexpensive but since they can be focused and easily absorbed by the eye the maximum power is limited by the need to make them eye-safe.

Eye-safety is often a requirement for most applications. A common alternative nm lasers are eye-safe at much higher power levels since this wavelength is not focused by the eye, but the detector technology is less advanced and so these wavelengths are generally used at longer ranges and lower accuracies. They are also used for military applications as nm is not visible in night vision goggles unlike the shorter nm infrared laser.

Airborne topographic mapping lidars generally use nm diode pumped YAG lasers, while bathymetric systems generally use nm frequency doubled diode pumped YAG lasers because nm penetrates water with much less attenuation than does nm Figure3.

Scanner and optics How fast images can be developed is also affected by the speed at which it can be scanned into the system. There are several options to scan the azimuth and elevation, including dual oscillating plane mirrors, a combi- nation with a polygon mirror, a dual axis scanner.

Optic choices affect the angular resolution and range that can be detected. Photo detector and receiver electronics two main photo detector technologies are used in lidars: solid state photo detectors, such as silicon avalanche photodi- odes, or photo multipliers.

Position and navigation systems LIDAR sensors that are mounted on mobile platforms such as airplanes or satellites require instrumentation to determine the absolute position and orientation of the sensor.

This position is then displayed, perhaps with a moving map display or latitude and longitude; elevation information may be included. Many GPS units show derived information such as direction and speed, calculated from position changes. However, even a very small clock error multiplied by the very large speed of light the speed at which satellite signals propagate results in a large positional error. A few specialized GPS applications do however use the time; these include time transfer, traffic signal timing, and synchronization of cell phone base stations.

The output of incremental encoders provides information about the motion of the shaft which is typically further processed elsewhere into information such as speed, distance, RPM and position. The output of absolute encoders indicates the current position of the shaft, making them angle transducers. Rotary encoders are used in many applications that require precise shaft unlimited rotationincluding industrial controls, robotics, special purpose photographic lenses, computer input devices such as up to me- chanical mice and trackballs , and rotating radar platforms.

Generations 13 were used to take photographs in the United States. The first generation was quickly superseded and images were replaced with images taken with 2nd and 3rd generation cameras. Second generation cameras were used to take photographs in Australia. The system is a rosette R of 15 small, outward-looking cameras using 5 megapixel CMOS image sensors and custom, low-flare, controlled-distortion lenses.

The shadows caused by the 1st, 2nd and 4th generation cameras are occasionally viewable in images taken in mornings and evenings. The new 4th generation cam- eras HD will be used to completely replace all images taken with earlier generation cameras.

Thus the total sensor components can be explained using the above figure as- sembled on the car. All the components are already explained.

It was launched on May 25, , originally only in several cities in the United States, and has since gradually expanded to include more cities and rural areas worldwide. Google Street View displays images taken from a fleet of specially adapted cars.

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