As cars move towards independence from drivers, and become more self-reliant, they are also becoming smarter and safer. Manufacturers are using newer systems every year for the assistance of drivers with the systems increasingly employing advanced technology and data processing. Among such advanced technology range from automatic high-bean control to pre-collision braking systems, and these are now becoming the norm in practically all kinds of cars.At present, the active safety systems manufacturers use in cars are mainly in the form of three major sensors – LIDAR, radar, and cameras. While assisting drivers in cars, these sensors offer benefits in different ways. Manufacturers also combine these with other sensors for achieving better solutions.
Light Detection and Ranging – LIDAR
This technology relies on lasers to measure distance. When used for automotive applications, the LIDAR system uses infrared lasers firing hundreds of pulses every second. The system measures the time of flight for the reflected light to return to the sensor. The distance to the object is then half of the time of flight times the speed of light.
LIDAR systems are in use by major car manufacturers, including Toyota, Volvo, Continental, and Infinity. These and other manufacturers often combine LIDAR sensors with other technologies such as radar and cameras to provide additional information. For instance, the MFL system from Continental combines LIDAR with a multifunctional camera that Toyota uses for providing automatic high-beam control, lane departure alert and a pre-collision system.
Radio Detection and Ranging – RADAR
One of the oldest and predominant sensor technologies, radar is used for advanced driver safety systems in automotive applications. These safety systems measure the time of flight, frequency shift, and the amplitude of the return signal for determining the relevant information. Automotive applications use radar systems for monitoring blind spots and provide warning for forward collision.
Similar to the LIDAR sensors, other technologies are used in conjunction with radar to obtain better information. By combining a camera and radar into a single package system, mounted in front of the rearview mirror inside the car, it offers multiple functionality such as traffic sign recognition, headlight control, object detection, pedestrian detection, full autonomous braking, pre-crash collision mitigation, forward collision warning, headway alert, lane departure warning/lane keeping, and full-speed adaptive cruise control.
Daylight and Night Vision Cameras
Driver assistance systems majorly rely on cameras, either on their own or by augmenting other systems using computer vision algorithms. Powerful processors extract valuable data using sophisticated image processing in real time. Some cars contain multiple cameras for providing different forms of data to the driver.
Cameras are also useful in assisting the driver to remain attentive when driving. For instance, the Driver Status Monitor from DENSO uses a system of cameras for detecting the driver’s head position, drowsiness level, long-duration eye closure, and the face angle to determine if the driver is distracted of drowsy. IR LEDs provide illumination for nighttime detection. The system then produces a suitable warning for the driver.
In the Future
A decade ago, such systems would be part of science fiction and even five years earlier, these safety systems were part only of luxury vehicles. However, these are commonplace now. Maybe, within the next five to ten years, self-driving cars will be the norm and people will take these and other safety systems for granted.
