UGV navigation control technology
SMP Robotics has developed a UGV navigation control technology that allows driving on and off roads, in urban forest and other natural terrain environments. A unique feature of the autonomous navigation control system is the ability to perform in the absence of a satellite navigation system signal and ensure precise navigation. This technology is best suited to applications that involve driving on the same route (circular driving) because driving accuracy will increase with each circle. A particular advantage of this innovative UGV navigation control technology is reliability and effective performance at any time of the day or night in all seasons.
A key feature of the developed UGV navigation control technology is a computer vision systems integrated into the ground robot. Three video systems ensure safe navigation of an off-road UGV.
The first system includes stereo cameras that detect obstacles and let the robot avoid them by correction of its path. The second system consists of a camera directed on the road and a PC. After having analyzed video data the PC displays the road with the aim to confirm possible driving path. This system allows the robot to drive on the pathway only 10-20 cm wider its track width.
The third system analyzes video images from distance viewing video cameras and allows the vehicle to orient itself with respect to the terrain. After the first operator-guided run the system compiles a digital map with visual landmarks. In the autonomous driving mode not requiring operator’s involvement the algorithm compares on-line video data with previously recorded digital map and after that determines vehicle’s current position.
When orientation by visual landmarks is impossible navigation continues on the basis of data received from an inertial navigation system and its microelectromechanical sensors.
The described technology is a low-cost solution unlike other solutions based on expensive LIDARs, which is a considerable advantage at a mass production stage.
Using the described navigation system maximum speed of a UGV heavily depends on the processing capacity of a video data analyzing computer. General purpose microprocessors available in 2013 have sufficient capacity to ensure UGV safe driving at 20 kph in the daytime.
Current status of the robot’s systems is transmitted to the operator’s table PC via WiFi. Android user interface allows the operator to distantly monitor robot operation and tasks it performs, view recordings made by robot’s video cameras and check robot’s position on a digital map.
To ensure continuous performance without operator’s involvement a UGV is equipped with a wireless charging system. The system includes one or more transmitting units buried at the points where the robot stops for long-term surveillance or at its home station and a receiving unit fitted to the robot bottom. The robot automatically visits the charging point and stops in the position to let the receiving unit and the transmitter combine, which creates an electromagnetic coupling and ensures power transmission to built-in accumulators. Complete recharging takes 2-3 hours.
