An automatic collision avoidance approach to assist remotely operated quadrotors

Abstract

The use of quadrotors to civilian and military missions has been increased and the challenges involved on controlling it, mainly in indoors and restricted environments, has been attracting robotics researchers. Thus, an automatic collision avoidance approach is of utmost importance in this scenario, given the difficulty of control and the risk of accidents involved in the use of these vehicles. This paper presents an approach for obstacle avoidance of a manually controlled quadrotor automatically, allowing the operator to keep focus on the overall mission. The method is based on constantly estimating its future path considering its dynamics, current status, current control and distances measured by four on-board sonar sensors. Simultaneously, the pose is estimated based on the quadrotor odometry and an occupation grid representation of the nearby environment is constructed using the sonar sensors measurements. All that information is used to determine an imminent collision and overrides the user control, if necessary, keeping its last safe position. All the solution was evaluated in a simulator, the real quadrotor’s and sonars sensors were characterized to be embedded in the quadrotor through a computer-on-module and controlled over wireless network communication.