An Integrated Delta Manipulator for Aerial Repair: A New Aerial Robotic System

Abstract

Unmanned Aerial Vehicles (UAVs) are capable of entering hazardous areas and accessing hard-to-reach locations at high altitude. However, small-scale UAVs are inherently unstable when exposed to challenging environments. Additionally, their capability to interact with infrastructure with high accuracy is limited due to the need to stabilize the vehicle precisely in flight. To address these challenges, this article introduces a new aerial robotic system with an integrated light-weight Delta manipulator and a kinematics-based approach allowing it to compensate fluctuations of the quadrotor platform due to wind or flight imprecision. Integrating onboard visual-inertial (VI) odometry-aided navigation, the system is characterised in various operation modes, including hovering in windy conditions. The end-effector accuracy of the integrated aerial robot is analysed and compared to the flight accuracy of the quadrotor platform using a 3D motion capture system for ground truthing. The results reveal that the end-effector of the aerial robot achieves a maximum decrease of the root-mean-square-error (RMSE) of 76.4%, 44.1% and 35.8% in X, Y and Z directions respectively in VI odometry-aided tests with 1 m/s wind along Y direction. In the same tests, the maximum fluctuations decrease by 52.8%, 46.9% and 33.6% in the directions of X, Y and Z. As a demonstration of the utility of this stabilised manipulator, we present the design of an on-board extrusion system that can deposit two component LD40 polyurethane foam for precise spot repairs. We selected the LD40 foam as the amorphous repair material due to its substantial expansion rates after deposition that allows for effective area coverage with little material carried on-board. We then demonstrate a complete aerial repair mission for sealing cracks and holes on a section of a standard oil pipe, by autonomously depositing the two component foam on the damaged areas. This work will enable a number of potential applications, including aerial repair at high altitude where access is difficult for ground vehicles and dangerous for human workers.

A review of collective robotic construction

“…Hardening foams (10,11,30,53) Fibers (31,35,66,75) Concrete (2,28) Material binders Active and passive interlocking features (48,64,74,76) Magnetism (13,27) Glue (15,36,57) Melted plastic filaments (77) Living plants (63) by guest on December 13, 2020…”

TiltDrone: A Fully-Actuated Tilting Quadrotor Platform

“…U NMANNED Aerial Vehicles (UAVs) with multirotor configurations have gained popularity in aerial robotics research [1], enabling a variety of applications, from close proximity infrastructure maintenance to ecological monitoring [2]- [6]. Conventionally, rotors are fixed perpendicularly to the plane of the platform with steering achieved by differential thrust.…”

Fully-Actuated Aerial Manipulator for Infrastructure Contact Inspection: Design, Modeling, Localization, and Control

“…However, in recent years, the appearance of robotic aerial manipulation has widened the application range of these UAVs. Aerial manipulators [ 3 , 4 ] are aerial robots with arms or mechanical devices which are able to physically interact with the environment, performing tasks as object manipulation [ 5 , 6 ], operating devices [ 7 , 8 ], surface repairing [ 9 ], and taking measurements with sensors in contact with surfaces [ 10 ].…”

“…On the other hand, the aerial robot in [ 25 ] and most aerial manipulators [ 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 ] use standard multirotor configurations with 4, 6, or 8 co-planar propellers. They are, therefore, under-actuated robots that need to tilt to move or apply forces in the horizontal plane.…”