  In this paper, we first present a method to autonomously detect helipads in
real time. Our method does not rely on any machine-learning methods and as such
is applicable in real-time on the computational capabilities of an average
quad-rotor. After initial detection, we use image tracking methods to reduce
the computational resource requirement further. Once the tracking starts our
modified IBVS(Image-Based Visual Servoing) method starts publishing velocity to
guide the quad-rotor onto the helipad. The modified IBVS scheme is designed for
the four degrees-of-freedom of a quad-rotor and can land the quad-rotor in a
specific orientation.
