We present a system consisting of a miniature unmanned aerial vehicle (UAV) and a small carrier vehicle, in which the UAV is capable of autonomously starting from the moving ground vehicle, tracking it at a constant distance and landing on a platform on the carrier in motion.Our visual tracking approach differs from other methods by using low-cost, lightweight commodity consumer hardware. As main sensor we use a Wii remote infrared (IR) camera, which allows robust tracking of a pattern of IR lights in conditions without direct sunlight. The system does not need to communicate with the ground vehicle and works with an onboard 8-bit microcontroller. Nevertheless the position and orientation relative to the IR pattern is estimated at a frequency of approximately 50 Hz. This enables the UAV to fly fully autonomously, performing flight control, self-stabilisation and visual tracking of the ground vehicle.We present experiments in which our UAV performs autonomous flights with a moving ground carrier describing a circular path and where the carrier is rotating. The system provides small errors and allows for safe, autonomous indoor flights.

We present a system consisting of a miniature unmanned aerial vehicle (UAV) and a small carrier vehicle, in which the UAV is capable of autonomously starting from the moving ground vehicle, tracking it at a constant distance and landing on a platform on the carrier in motion.Our visual tracking approach differs from other methods by using low-cost, lightweight commodity consumer hardware. As main sensor we use a Wii remote infrared (IR) camera, which allows robust tracking of a pattern of IR lights in conditions without direct sunlight. The system does not need to communicate with the ground vehicle and works with an onboard 8-bit microcontroller. Nevertheless the position and orientation relative to the IR pattern is estimated at a frequency of approximately 50 Hz. This enables the UAV to fly fully autonomously, performing flight control, self-stabilisation and visual tracking of the ground vehicle.We present experiments in which our UAV performs autonomous flights with a moving ground carrier describing a circular path and where the carrier is rotating. The system provides small errors and allows for safe, autonomous indoor flights.

The growth of civil and military use has recently promoted the development of unmanned miniature aerial vehicles dedicated to surveillance tasks. These flying vehicles are often capable of carrying only a few dozen gramms of payload. To achieve autonomy for this kind of aircraft novel sensors are required, which need to cope with strictly limited onboard processing power. One of the key aspects in autonomous behaviour is target tracking. Our visual tracking approach differs from other methods by not using expensive cameras but a Wii remote camera, i.e. commodity consumer hardware. The system works without stationary sensors and all processing is done with an onboard microcontroller. The only assumptions are a good roll and pitch attitude estimation, provided by an inertial measurement unit and a stationary pattern of four infrared spots on the target or the landing spot. This paper details experiments for hovering above a landing place, but tracking a slowly moving target is also possible.

Abstract-We present a follow-the-leader scenario with a system of two small low-cost quadrocopters of different types and configurations.The leader is a Parrot AR.Drone which is controlled by an iPad App utilizing the visual odometry provided by the quadrocopter and pilots it autonomously. The follower is an Asctec Hummingbird which is controlled by an onboard 8-bit microcontroller. Neither communication nor external sensors are required. A custom-built pan/tilt unit and the camera of a Nintendo Wii remote tracks a pattern of infrared lights and allows for online pose estimation. A base station allows for monitoring the behavior but is not required for autonomous flights.Our efficient solution of the perspective-3-point problem allows for estimating the pose of the camera relative to the pattern in six degrees of freedom at a high frequency on the microcontroller. The presented experiments include a scenario in which the follower follows the leader with a constant distance of two meters flying different shapes in narrow, GPS-denied indoor environment.

Abstract-In this paper, we compare three different marker based approaches for six degrees of freedom (6DOF) pose estimation, which can be used for position and attitude control of micro aerial vehicles (MAV). All methods are able to achieve real time pose estimation onboard without assistance of any external metric sensor. Since these methods can be used in various working environments, we compare their performance by carrying out experiments across two different platforms: an AscTec Hummingbird and a Pixhawk quadrocopter. We evaluate each method's accuracy by using an external tracking system and compare the methods with respect to their operating ranges and processing time. We finally compare each method's performance during autonomous takeoff, hovering and landing of a quadrocopter.