30-06-2012, 01:11 PM
Cross Traffic Alert with Blind Spot Detection for Automotives
Cross Traffic Alert with Blind Spot Detection for Automotives.docx (Size: 368.6 KB / Downloads: 77)
INTRODUCTION
1.1 The Modern Car
1.1.1 Present and Future Car Technologies Overview
As the technology advances day-after-day, car manufacturers and developers provide with more sophisticated, high technology cars and vehicles. We are living in the Smart car era. Figure 1.1 illustrates features available in a typical modern car. This car utilizes an engine control system that optimizes performance and fuel combustion, a system that detects collisions and activate the airbags in the event of a crash, a system that regulates the interior climate based on passenger preferences and exterior climate conditions, a system that controls the braking system for maximum efficiency, a GPS navigation system to aid driver approach his destination in most efficient ways, and much more. In fact, modern car – now a day - may contain up to a 100 microprocessor and microcontroller systems that together manifest all these features.
According to statistics, vehicle accidents caused 40,000 deaths and 3.5 million injuries annually. In a given two-hour period, 1,600 accidents, 800 injuries, and 10 deaths will occur on U.S. highways. The ultimate goal of cars manufacturers is to come up with safe, driver-friendly add-on systems to ensure the safety of drivers, passengers and pedestrians. This may, in some way or another minimizes car accidents and injuries.
Safe driving support systems are starting to appear on vehicles including adaptive cruise control (ACC) systems that maintain safe distance between you and the vehicle ahead, lane keep support (LKS) systems that prevent drivers from departing lane, and pre-crash brake systems that automatically tighten seat belts, activate air-bags and apply brakes if a collision cannot be avoided. Ultrasonic, Millimeter-wave and Infrared Radars and image processing cameras are the environment sensors with the key roles of recognizing and deciding what action to take in these safe driving support systems. These sensors must incorporate intelligent recognition technologies considering various complex external factors they might encounter in the real world: pedestrians darting out into the road, other vehicles cutting-in in front of you, poor visibility due to adverse weather conditions, etc. Symbols and signals in a car must provide the driver with accurate information about the car’s status, and with clear warnings of critical situations. The visual aspect frequently dominates inconvenience functions. A graphical icon or symbol, for instance, may clearly demonstrate available options and appropriate actions the driver can take to back into a parking space or to change into new lane. In addition, acoustic (audible) signals can denote the start and finish of required steering, backing-up and braking actions.
1.1.2 The Parking Space Finder Service
This is one of the most promising (hot) schemes in the field. The objective of the PSF service is to use feeds from cameras installed in parking lots in a metropolitan area and allow users to make queries about the availability of parking spots at a particular location. The microcomputers used in this service processes the webcam feed and recognize whether the parking spots are empty or full. Users specify a destination and constraints of their desired spot. The PSF service returns the driving directions (using the Yahoo Maps service) to the empty parking spot that satisfies the constraints and is the nearest to their destination.
1.1.3 Parking Assistant Systems
With increasing traffic density, especially in urban areas, parking can be a tricky maneuver and an error can be costly, in the event of contact with other parked cars or hidden obstacles. Such accident repairs are more and more frequent and expensive. Drivers can prevent such costly, time consuming and stressful situations by selecting an Ultrasonic Park Assist (UPA) system when buying a new vehicle or installing any of the commercially available kits as post-equipment, both of which cost less than the average accident repair.UPA is available for rear applications using two to six sensors mounted discreetly behind the rear bumper or a combined front and rear system using eight to twelve sensors. Figure 1.3 shows a typical four-sensor reverse parking aid. Figure 1.4 shows - from three different views - how the system is installed and highlights the range covered by the three sensors. This system provides a visual or acoustic warning, which alerts the driver of the presence of, and distance to any obstacles to the rear or front of the vehicle. Various display and audio options are available.
Car Traffic Alert with Blind-Spot Detection System
2.1 System Overview
It is every driver's nightmare is changing lanes suddenly, glancing in the rearview mirror without looking over your shoulder and you merge directly into a car hidden in one of your car's blind spots. Yes, that is true. Every car has a blind spot the area behind the car where cannot be seen from driver seat. According to recent statistics, more than 500,000 vehicles are involved in lane-change blind-spot collisions annually. Furthermore, the U.S. National Highway Traffic Safety Administration says that "lane change situations" are involved in 4 to 10 percent of all car crashes. So, we are talking about a serious problem here.
To solve this problem and maintain car's safety, the driver must make sure that the blind-spots of the vehicle are clear before he attempts to change lanes. The goal is to have a system that would detect objects present within the blind-spot of the car, on either side of the vehicle (left/right), and appropriately warn the driver if the turn signal was on. The warning mechanism can be audio warning by a buzzer, or beeper. In addition, the system can display the distance measurement of the object present in the blind-spot on an LCD. The system will detect the presence of vehicles within the detection zone, as shown in Figure 2.1 by use of sensors. The detection zone is fixed. The zone extends from one to five meters to the side of the vehicle to allow the traffic in the adjacent lane to move freely. The zone does not extend more than twenty meters back from the rear of the car. Objects detected will not be limited to cars, as vehicles such as motorcycles will be present in some situations. Sensors employed in design are so sensitive that they ensure the detection of an object the size of a pole or broom's handle.
2.2 History behind the invention of the Technology
• The Blind Spot Detection system was first patented by Aric David Shuffer of USA. 2004.
• The Blind Spot Detection system was later added with a Cross Traffic Alert device by Shuqing zeng of USA. 2009.
• The system was later assigned to GM GLOBAL TECHNOLOGIES USA
• The below graphical representation shows the decrease in collision between cars in thousands from the year 2004-2011
2.3 What is a Blind Spot Mirror and Cross Traffic Alert with Blind Spot Detection system?
The Cross Traffic Alert with Blind Spot Monitoring System is a radar-based blind spot detection system with the additional capability to help customers confidently back out of a parking space even when there is traffic approaching from the sides.
Both of these features were demonstrated by Ford by listening closely to customers and responding to customer demand for increased visibility.
• Blind Spot Mirror: - The Blind Spot Mirror is a consumer-friendly, affordable blind spot solution that consists of an outside rearview mirror designed with a secondary convex spotter in the top outer corner, which is aimed exclusively at the driver's blind spot. When traffic enters the driver’s blind spot on either side of the vehicle, it is visible in the secondary convex mirror, thus alerting the driver of potential danger.
• Cross traffic alert with BSD: - Backing out of a crowded spot in a bustling parking lot, or into street traffic, can be difficult. Drivers sometimes inch their way out with limited visibility on either side, counting on cross traffic to see their vehicle.
Cross Traffic Alert feature will assist drivers in backing up by warning drivers of impending traffic while backing out. The feature works in conjunction with radar-based Blind Spot Monitoring System, utilizing this system’s two multiple beam radar modules, which are packaged in the rear quarter panels – one per side. The radar identifies when a vehicle enters the defined blind spot zone and illuminates an indicator light on the corresponding side view mirror providing a warning that a vehicle is approaching.
Cross Traffic Alert uses the radar when in reverse to pick up moving objects within a 65-foot range from either the left or right side of the vehicle. The radar also works when backing out of angled parking spaces because its view is wider than just strictly sensing traffic coming at a 90-degree angle. Conventional systems have limited sideways effectiveness. When cross traffic is approaching, two warnings are given: an indicator lights up in the corresponding outside mirror and an audible alert is sounded.