Bosch Manufactures One-Millionth Radar Sensor
When driving a car, the most important point of reference is the vehicle in front. How far ahead is it, and how fast is it traveling? What humans can only estimate, radar sensors can measure with extreme precision around 20 times a second – which is why they form the basis of numerous powerful assistance systems. These systems automatically maintain chosen pre-selected distance from the car ahead, and in critical situations they provide warnings and hit the brakes of their own accord. At the time of writing, Bosch is manufacturing at its Reutlingen location near Stuttgart its millionth radar sensor that utilizes the 77 GHz frequency band. Series production began in 2000. For a long time volumes remained small, but now they are growing rapidly. While it took 13 years to reach the one-million mark, the next million will roll off the production lines in little over a year. “Driver assistance will experience a real boom in the coming years,” says Wolf-Henning Scheider, describing the dynamic affecting the sector for which he is responsible as member of the Bosch board of management. “Bosch will be delivering its ten-millionth radar sensor come 2016.”Driver-assistance market experiencing double-digit growth
Automakers are using the growing number of assistance functions as a way of standing out from the competition. A further major driver of this growth is Euro NCAP's future rating process: from 2014, a car will have to feature at least one assistance system to receive a five-star rating, and from 2016 comprehensive pedestrian safety will be mandatory. But once sensors are on board, they can of course serve many other functions. A camera that detects lane markings can for instance also record traffic signs. Drivers will come to appreciate these safety and comfort features more and more. “The driver-assistance market will see annual growth of over 20 percent over the next few years,” Scheider says.
Bosch offers comprehensive systems competence
Powerful assistance systems call for the comprehensive integration of several in-vehicle systems. Assistance systems combine data from a wide range of sensors to form a unified map of the vehicle's surroundings, with the engine, brakes, and steering carrying out the instructions computed on the basis of that map. In the words of Gerhard Steiger, president of the Bosch Chassis Systems Control division, the supplier of technology and services has more than just a high level of systems competence: “For driver assistance, Bosch has all the necessary capabilities in-house.”
Bosch is looking to help shape the coming years by way of new technology and new functions. The company is about to start series production of the new mid-range radar sensor, which is just as powerful as its predecessor but more compact and considerably more affordable. The sensor is available in front and rear versions. In 2014 production will get underway for a stereo video sensor that can measure distances of up to around 50 meters. For the first time, therefore, just one sensor is needed for automatic emergency braking to enhance pedestrian safety. In the future, new functions will play a bigger role in helping to steer vehicles. For instance, they will use ultrasound sensors to park fully automatically, even if the driver is standing outside the car, and they will steer through narrow construction zones sites on freeways. “Each innovation brings us a little bit closer to accident-free, automated driving,” says Steiger. The degree of automation will slowly increase at first, initially on freeways. Starting in 2014, drivers will be able to choose a series-production traffic jam assistant developed largely by Bosch. At low speeds, this function steers fully automatically, although the driver retains overall responsibility. Over time, assisted freeway driving will become successively more automated at ever higher speeds, finally reaching the point when the highway pilot will automatically take care of all the driving, from approach road to exit ramp. Steiger is convinced that “fully automated driving will come about in many small steps.”
Comprehensive portfolio of radar sensors
Since the start of series production for the first generation of radar sensors, Bosch has worked intensively to improve the technology. The second generation saw a doubling of both range and aperture angle. The third and current series-production generation, the LRR3 long-range radar sensor, offers an even wider aperture of 30 degrees and a range of up to 250 meters. What is more, the high-frequency module of this Bosch sensor is the first to feature silicon-germanium technology, which brings down manufacturing costs substantially. “With each generation we have managed to halve costs and double performance,” says Dr. Bernhard Lucas, department head for radar components engineering.
The mid-range radar sensor is about to enter series production. Its aperture angle of 45 degrees and range of up to 160 meters enable all emergency braking functions to be implemented, as well as adaptive cruise control up to 150 kilometers per hour – sufficient for almost any country in the world. Production of a version for use at the rear of the vehicle will begin in 2014; this will allow early detection of vehicles approaching quickly from behind and thus warn of collisions when changing lanes. With an aperture angle of 150 degrees, it can survey a particularly wide area.
All Bosch radar sensors use the 77-gigahertz frequency band. Compared to 24-gigahertz versions, a 77-gigahertz sensor is more powerful in every respect: its object separation is up to three times more accurate, and it can measure speed and distance three to five times more accurately. Since this higher frequency band has been permanently allocated to automotive applications worldwide, it is particularly suitable for global vehicle platforms.