Aerial Device Delivery for Power Line Inspection and Maintenance

Abstract

The inspection and maintenance of power lines with aerial robots requires to decrease as much as possible the performance time given the limited capacity of the batteries and the vast extension of this kind of infrastructure. In order to avoid the waste of time associated to the take-off and landing maneuvers, this paper proposes the use of aerial manipulation robots for fast and safe delivery in flight of devices and tools. Two use cases are considered. In the first one, a device delivery multirotor (DDM) is used as supplier for a device installation robot (DIR), consisting of a dual arm aerial manipulator in long reach configuration. The vertical separation distance between DIR and DDM associated to the long reach link contributes to reduce the risk of collision and the downwash effect over the DDM. In the second case, the DIR is used to deliver tools to human operators quickly and safely, avoiding hazardous situations during the handover thanks to the long reach configuration. The paper also analyzes the aerodynamic downwash effect of two multirotors flying vertically at distances determined by the long reach link through Computational Fluid Dynamics (CFD) simulation. Experimental results in an indoor testbed validate the proposed application.

A Review of Real-Time Implementable Cooperative Aerial Manipulation Systems

“…Outdoor path planning experiments are discussed in [37]; random tree star (RRT*) algorithms are implemented for a quadrotor with two arms path planning for long-reach manipulation in cluttered environments. Dual arm manipulators are also adopted in [38], although in a cable suspended configuration; they are suitable for aerial tool delivery to human operators performing power line inspection tasks. Increased dexterity and the need to replicate human hands has lead to prototypes as in [39], where 4-DoF anthropomorphic dual arms are integrated with a hexarotor.…”

Dual Arm Aerial Manipulation While Flying, Holding and Perching: Comparative Case Study

“…where 𝑭 𝑩 𝑬 and 𝝉 𝑩 𝑬 are forces and moments acting on the multirotor base, 𝝉 𝑠 𝑖 are 𝝉 𝑖 the servo and output link torques in the compliant joints, whereas 𝑭 𝟎 𝑩 and 𝝉 𝟎 𝑩 are the forces and torques acting on the manipulator base that tend to cause a position and orientation deviation with respect to the multirotor base. These wrenches do not apply when the arms are rigidly attached to the multirotor base, but they should be considered in the long reach [15] or cable suspended configurations [25] (see Section 3). Depending on how the manipulator is attached to the multirotor base, the time derivatives of some coordinates of ∆𝒓 𝟎 𝑩 and 𝜼 𝟎 𝑩 will be zero, so these can be removed from the dynamic model.…”

“… The configuration of the manipulator when integrated in the multirotor platform: (1) standard, in which the arms are rigidly attached at the multirotor base [14][16], (2) long reach, also known as passive pendulum [15], or (3) cable suspended [25].  The operation mode: flying [15], holding with one arm while the other conducts the operation [16], or perching/landed so there is no dynamic coupling on flight [22].…”

“…This configuration enhances safety by increasing the separation distance between the manipulator and the propellers to reduce the risk of collision during the realization of manipulation tasks like the installation of bird flight diverters on power lines [5]. The use of four cables instead of two as in [25] is motivated by the convenience to avoid the counter-rotation in pitch of the shoulder base when the arms lift a load, so the 4-CS prevents the roll-pitch rotations, resulting in a horizontal position deviation. This corresponds to the term ∆𝛆 𝟎 𝑩 in Equation ( 2), where 𝜀 𝑧 ≅ 0, and the only relative orientation angle of {𝟎} w.r.t.…”

Projection operator‐based robust adaptive control of an aerial robot with a manipulator

“…Several UAM designs have been proposed and studied in the literature, each specific to the task. For example, in Suarez et al (2022), a cable‐suspended dual‐arm aerial manipulator mounted on a multi‐rotor is considered for the fast delivery of devices (tools) to an operator performing power‐line maintenance. These cable suspensions are long‐reach links that reduce the risk of collision and down‐wash effects on the operator.…”