Towards Vision-Based Impedance Control for the Contact Inspection of Unknown Generically-Shaped Surfaces with a Fully-Actuated UAV

Abstract

The integration of computer vision techniques for the accomplishment of autonomous interaction tasks represents a challenging research direction in the context of aerial robotics. In this paper, we consider the problem of contactbased inspection of a textured target of unknown geometry and pose. Exploiting state of the art techniques in computer graphics, tuned and improved for the task at hand, we designed a framework for the projection of a desired trajectory for the robot end-effector on a generically-shaped surface to be inspected. Combining these results with previous work on energybased interaction control, we are laying the basis of what we call vision-based impedance control paradigm. To demonstrate the feasibility and the effectiveness of our methodology, we present the results of both realistic ROS/Gazebo simulations and preliminary experiments with a fully-actuated hexarotor interacting with heterogeneous curved surfaces whose geometric description is not available a priori, provided that enough visual features on the target are naturally or artificially available to allow the integration of localization and mapping algorithms.

Energy Aware Impedance Control of a Flying End-Effector in the Port-Hamiltonian Framework

“…The spring wrench corresponding to (45) will consequently contain extra terms compared to (19) which can be shown to be equal to [6]…”

“…W B c in (11), which is always possible within the limits of the actuators, assumed to be the nominal working condition. A thorough description of the physical parameters of the robot as well as technical details on the software architecture and the sensors used in the experiments can be found in [45]. The demonstrations took place in two indoor environments endowed with motion capture systems to provide reliable estimates of the robot configuration and twist, as the contributions of the paper are clearly focused on control rather than perception: scenarios e-I -e-III were performed in a small flight lab (4.33 × 2.81 × 2.62m), while scenarios e-IV -e-V were carried out in a larger indoor arena (7.43×5.93×5.93m).…”

Observer-based Geometric Impedance Control of a Fully-Actuated Hexarotor for Physical Sliding Interaction with Unknown Generic Surfaces

“…3) The effectiveness of the presented strategy is demonstrated on a fully-actuated hexarotor manipulator prototype [15][16][17] in several realistic numerical simulations with ROS [13]./Gazebo [9]./RotorS [3], automatically sliding on multiple curved surfaces whose geometric descriptions are not available a priori.…”

A General Control Architecture for Visual Servoing and Physical Interaction Tasks for Fully-actuated Aerial Vehicles

“…This has largely encouraged the research community to adopt fully-actuated aerial robots in heterogeneous contactbased applications [4], [10]. In order to physically interact with the environment, these robots have been equipped with perceptive sensors, like cameras and infrared sensors, and consequently, several perception-based control strategies and algorithms have been proposed [11], [12]. Among all the sensor possibilities, monocular and stereo vision cameras have become the de facto standard in the onboard sensing equipment of every aerial robot, thanks to their lightweight, affordable price, compact dimensions, and the availability of numerous open-source video-processing software packages.…”