Relative positioning-based system with tau control for collision avoidance in swarming application

In this paper, a relative positioning system by fusing infrared and ultrasonic range sensors data is employed to provide a more reliable relative distance data between quadcopters to achieve close proximity formation flight. This is due to lack of accuracy of positioning data from GPS due to its error of two to five meters. A leader-follower formation control strategy is used to control the distance between the quadcopters by applying data from the relative positioning system. An experiment to test the capability of the proposed strategy was done in the test platform environment equipped with Optitrack motion capture camera. Tau control was implemented as a braking system for the follower to avoid aggressive maneuvers that will make the quadcopters having high pitch along the formation control, which will affect the range detection of sensors. It has been proven from the results that close proximity formation flight is able to be achieved.