COOPERATIVE ADAPTIVE CRUISE CONTROL
Embed Size (px)
Transcript of COOPERATIVE ADAPTIVE CRUISE CONTROL
CACC based on UART Protocol using Microcontroller 2015-16
CACC based on UART Protocol using Microcontroller 2015-16 CACC based on UART Protocol using Microcontroller 2015-16
Significant developments in advanced driver assistance systems (ADAS) have been achieved during the last decade. Intelligent systems based on on-board perception/ detection devices have contributed to improving road safety. The next step in the development of ADAS points toward vehicle-to-vehicle (V2V) communications to obtain more extensive and reliable information about vehicles in the surrounding area, representing cooperative intelligent transportation systems (ITS).Using wireless communication, potential risk situations can be detected earlier to help avoid crashes, and more extensive information about other vehicles motions can help improve vehicle control performance. 1.1 INTRODUCTION TO COOPERATIVE ADAPTIVE CRUISE CONTROL
Research projects have been conducted throughout the world to define the requirements for an appropriate vehicular communication system and its possible applications. Although most of the V2V cooperative ITS applications have been focused on improving collision avoidance and safety, the extension of the commercially available adaptive cruise control (ACC) system toward the cooperative ACC (CACC) system has a high potential to improve traffic flow capacity and smoothness, decreasing obstruct on express highways. By introducing V2Vcommunications, the vehicle gets information not only from its preceding vehicleas occurs in ACCbut also from the vehicles in front of the preceding one. Due to this preview information, oscillations due to speed changes by preceding vehicles can be drastically reduced. The present CACC framework is used to distinguish the crash of the vehicle. There were various troubles to overcome in doing this gadget particularly controlling the speed and cruise the vehicle. To the association, it was a major up-lift. This kind of sign is used to manufacture a ultrasonic gadget which can recognize the deterrents and exchange the same over UART channel.1.2 MOTIVATION
CA (Collision Avoidance) systems are being used in a wide range of different areas and under very different circumstances. Typical sensors used to detect obstacles are radar, lidar or vision sensors. This section presents an overview of some of the important areas of application and highlights important issues.
Automotive Collision Avoidance Traffic accidents are one of the major causes of death and injuries in todays society. Automotive manufactures have started to introduce more and more driver support systems to help prevent accidents. The first step in CA systems for automotive applications is adaptive cruise control (ACC), which is currently available as an option for several car models. ACC systems adapt the speed to any in-path vehicle, should it travel slower than the set speed of the host vehicle. The cruise control system is only allowed to exert limited deceleration (typically 3 m/s2); some systems also issue a warning to the driver when this acceleration is not sufficient to avoid collision. Current ACC systems are sold as a comfort system and can be switched on and off by the driver; they also disengage at low speeds (below 40 km/h). The next step in automotive CA is to introduce systems that are always active and perform autonomous braking and/or give warning when a collision is imminent. Such systems are starting to emerge on the market]. A big challenge in automotive collision avoidance is that even in normal driving, the traffic situation might be very complex from a sensing view point, with numerous obstacles to be detected and classified. In addition to this, sensors and computational resources must be low-cost. Another issue is that often the tire-to-road friction is unknown and might change rapidly. Aerospace Applications Radar-based air traffic control (ATC) systems have been in use for several decades. Traffic alert and collision avoidance system (TCAS) has been used on board US transport aircraft since the beginning of 1990s. These systems typically aim at helping pilots and air traffic controllers in keeping a regulated minimum separation between any two aircraft. A breach of this distance is referred to as a conflict. This area becomes ever more interesting as the airspace surrounding large airports becomes more crowded. There exist different types of systems both in cockpit and on the ground to provide decision-support to pilots and air traffic controllers. Other applications of airborne collision avoidance are mid-air collision avoidance for fighter aircrafts. Here, the CA system also attempts to maintain a regulated minimum separation between aircrafts. Apart from issuing a warning the system may also be authorized to take over steering controls to perform a sneaky move to avoid collision.
1.3 OBJECTIVES Safe and collision-free travel is vital in todays society. It is also an important issue in many industrial processes. In aerospace and naval applications, radar based support systems to avoid collisions have been used for several decades.To build up a prototype to Safe and affect free travel is fundamental in today's overall population. To execute a vehicle with cruise control works by adaptive cruising and auto speed reduction when sensing is in collision course using ultrasonic.Dual control to do the process collision free cruising system. pulse width based speed control to dc motors.1.4 PROBLEM STATEMENT Using wireless communication, potential risk situations can be detected earlier to avoid crashes and more extensive information about other vehicles motions can help improve vehicle control performance.FEATURESUltrasonic sensor is used to measure the speed of the front vehicle.
Speed reduction will be motorized over pwm.1.5 SCOPE OF THE WORK
Collision Mitigation (CM) systems are given some perception of the environment surrounding the vehicle. Based on this perception the system takes steps to avoid or mitigate imminent collisions. The main scope of this thesis falls in this field. It must be pointed out that these systems are often called Collision Avoidance systems. The term avoidance might imply that accidents should be completely avoided by these systems. For a couple reasons, Collision Avoidance Overview systems that avoid all accidents are unattainable for auto applications. This thesis will therefore talk about CM systems. Generally, a CM system will try to reduce the severity of the accident as much as possible under some constraints. In the best case, accidents might be avoided altogether whilst in the worst cases the systems have no positive effect at all. The perception of a CM system can come from several sources. The environment may be perceived with radar sensors, laser radar, vision sensors, ultrasonic sensors, GPS sensors and inter-vehicle communication. Based on the information acquired from the sensors, the vehicle itself acts to prevent or mitigate collisions. Typical actions the systems can take to mitigate a collision are issuing a warning to the driver, applying the brakes, and changing the course of the vehicle by applying torque to the steering wheel. Other possible countermeasures might be activating the brake lights to avoid being hit from behind, early airbag inflation or adjusting the vehicles height to increase crash compatibility. Several systems exist or have been proposed with CM functionality:
1. Lane keeping aid system monitors the lane markings. Using the observations of the lane markings an estimate of the vehicles position in the lane can be obtained. Should the vehicle swerve out of the lane a warning can be issued or a steering intervention executed.2. Lane change helps systems screen ( monitor) the blind spot and some partition ( distance) behind the car. The system can then alert or intervene by adding controlling (steering) wheel torque to keep up a vital separation from an accident while trading way
3. Forward collision mitigation systems monitor what is in front of the host vehicle and intervene to prevent or mitigate a frontal collision. Adaptive cruise control works like normal cruise control, but adapts the speed to the vehicle in front; if the driver is closing in on a vehicle in the same lane. ACC is really a CM system. The reason that it is dealt with separately here is that it is marketed as a comfort system that is switched on and off by the driver examples of ACC system on the market are: Toyotas Radar cruise control which is based on a lidar and was introduced in 1997; Merceds Distronic which is based on a mm-radar and was introduced in 1998; Jaguars Adaptive cruise control which is based on a mm-radar and was introduced in 1999, and BMWs Active Cruise Control which is based on a mm-radar and was introduced in 2002 .
1.6 ORGANIZATION OF THE REPORT
This report is organized as follows Chapter 2 portrays about the writing review taken from the specialized papers distributed in IEEE exchanges and reputed websites related to cruise control of vehicle.Chapter 3 clarifies about different equipment segments and programming software required.Chapter 4 portrays the structure of versatile journey framework and equipment execution.Chapter 5 gives the clarification of flowcharts of different modules of the project utilized for computerizing and controlling client module.Chapter 6 portrays the results of different test condition to check dependability of framework.Appendix A gives data about the microcontroller atmega-8 and atmega-16.
Appendix B gives information about ultrasonic and motor driver.
Literature SurveyThis chapter gives a broad of writings alluded from various IEEE papers and different papers published in various journals Profits