Development of Obstacle Avoidance Controller for MAVs: Testing in Hardware-In-Loop Simulation∗∗This work was sponsored by NP-MICAV Project No: DARO/081102072/M/I/CN-04.

Abstract

Abstract Most of the applications need the Miniature Aerial Vehicles (MAVs) to be capable to navigate in urban environment where many obstacles of different types and sizes like buildings, trees, etc. exist. So the main aim of autonomous MAV is the ability to detect obstacles in its path and avoid them for achieving a robust autonomous flight. Since, an accurate modelling of some critical hardware like actuators is difficult in the numerical simulation, an effective tool named Hardware-In-Loop Simulation (HILS) is used which replaces simulation models of some flight critical hardware like OBC, servos, and communication devices in the loop with actual hardware. The most important feature in the HILS setup is its capability to perform the Real-Time (RT) simulation. In the present work, a PC based Hardware-In-Loop Simulation (HILS) test bed is developed, which consists of Host PC, Target PC, Ground station PC, On-Board Computer (OBC) and RC Servos. A reactive Obstacle Avoidance Controller based on a pair of miniature LRFs is developed for achieving the autonomous flight of the MAV's in urban environment with street canyons and obstacles. The LRFs are forward looking and attached both sides of the MAV body at an angle 30° on both sides of the X-axis and rays aligned parallel to the body XY-axis. Range to obstacle measured by left and right LRFs are fed to two PID controllers which compute the required heading angle command for the MAV to turn. The Obstacle Avoidance (OA) controller is successfully implemented in Hardware-In-Loop Simulation (HILS) testbed, and performance is evaluated for various scenarios in which the MAV is simulated to fly in obstacle rich urban environment.