Chambers, radar and some other types of sensors can be hidden under a cowl or under plastic elements of a body of the car, but one of basic elements, the laser scanner, always sticks out ugly “cone” from above of a bumper or on a roof practically of any car robot. Such location of the laser scanner is caused by that control of a laser beam is exercised mechanically. It also serves as the reason of complexity of the device and its high cost because of which laser scanners for the present were not widely adopted and are used, generally on experimental cars. But soon such situation can change radically, thanks to work of specialists of Management of perspective research programs of the Pentagon of DARPA.
Quite recently representatives of DARPA showed new system of a class the laser – the scanner – on – the chip which allows to operate the direction of a laser beam in exclusively electronic way. The system is constructed on the basis of the known principle of the phased lattice which is rather widely used in radar technologies. The phased lattice consisting of a set of tiny radiators, each of which radiates the signals differing from each other on a phase which develop and form one beam directed in the set direction.
Like a radar lattice, the lattice of the new laser scanner allows to receive the synthesized laser beam sent to any point which is limits of admissible range. Thus, the speed of change of the direction of a beam is extremely high, the beam can move from one extreme situation to another with a speed about 100 thousand times a second, in 10 thousand times quicker, than mechanical control systems of the direction of a laser beam can do it.
According to tradition in the field of military development the new system received very long name – Short-range Wide-field-of-view Extremely agile Electronically steered Photonic EmitteR, in abbreviated form – Sweeper. This system covers space area within 51 angular degrees so far, nevertheless, it is the best result among similar systems – on – the chip. But, taking into account small dimensions and small cost of sensors chips, nothing prevents to place on the vehicle so many sensors, how many are necessary for ensuring full coverage of surrounding space with them.
The main problem which developers of the new chip of the laser scanner had to solve, creation of the phased lattice was. After all length of waves of light incommensurably is less than lengths of the most high-frequency radio waves used in a radar-location. “It means that cells of radiators of the matrix chip have to settle down at distance of several microns from each other. The deviation from the set point on only 100 nanometers leads to violation or to full loss of operability of the device in general” – researchers in the official statement write.
However, the problem was solved with the accuracy of production of the phased lattice by means of photolithographic “sorcery” which technology was developed by researchers from the Californian universities in Berkeley and Santa Barbara, Massachusetts Institute of Technology and several other organizations. Taking into consideration that for production of chips of laser scanners is not required any special equipment, representatives of DARPA are sure that this technology soon will come to the level of mass production. And it will serve as the reason of cardinal depreciation of such chips which will be used not only in military equipment, but also civil cars robots, in a robotics, in UAVs and in a set of other areas.