Aerial Grasping with a Lightweight Manipulator Based on Multi-Objective Optimization and Visual Compensation

Abstract

Autonomous grasping with an aerial manipulator in the applications of aerial transportation and manipulation is still a challenging problem because of the complex kinematics/dynamics and motion constraints of the coupled rotors-manipulator system. The paper develops a novel aerial manipulation system with a lightweight manipulator, an X8 coaxial octocopter and onboard visual tracking system. To implement autonomous grasping control, we develop a novel and efficient approach that includes trajectory planning, visual trajectory tracking and kinematic compensation. Trajectory planning for aerial grasping control is formulated as a multi-objective optimization problem, while motion constraints and collision avoidance are considered in the optimization. A genetic method is applied to obtain the optimal solution. A kinematic compensation-based visual trajectory tracking is introduced to address the coupled affection between the manipulator and octocopter, with the advantage of discarding the complex dynamic parameter calibration. Finally, several experiments are performed to verify the effectiveness of the proposed approach.

Robust Control Based on Adaptive Neural Network for the Process of Steady Formation of Continuous Contact Force in Unmanned Aerial Manipulator

“…Therefore, the force interaction can be regarded as a significant disturbance, and the research on this operation mainly focuses on the center of gravity compensation or the grasping path planning. Haoyao Chen et al formulated the trajectory planning for aerial grasping control as a multi-objective optimization problem, and introduced a vision-based trajectory compensation and tracking control method to address the external disturbance and the coupled affection between the manipulator and the octocopter [ 10 ]. Guangyu Zhang et al designed a UAM platform and proposed a controller that could compensate for the shift in the system’s center of mass, caused by the movement of the manipulator [ 11 ].…”

“…The research of UAM applications has gained some achievements in the last decade, including grabbing stationary or moving objects [ 10 , 11 ], picking up and transporting goods [ 12 , 13 , 14 ], inspecting infrastructure [ 15 , 16 ], and installing and retrieving equipment [ 17 , 18 , 19 , 20 ]. Continuous contact operations cause the UAM to lose its degree of freedom in a specific direction, so the stability control of the UAM can be more complicated.…”

Modeling and Control of Aerial Manipulation Systems: From Conventional to Continuum Manipulation

“…Owing to their extensive applications, many recent works have focused on developing effective aerial manipulation systems (AMSs) [49]. As a result, a variety of base platforms [99,50,18] and arms with different number of degrees-of-freedom [49,113] have been proposed to develop efficient and practical aerial manipulation systems. An emerging trend in aerial manipulation also includes reforming the arm types from rigid-link robots to soft [107] and continuum ones [106] to improve their operational capabilities.…”

Cartesian Aerial Manipulator with Compliant Arm

“…The development of this technology is motivated by interest in reducing the time, cost and risk for human workers associated with the realization of certain tasks in high altitude or difficult access workspaces such as power lines [1,2], chemical plants [3], oil and gas refineries [4], and other infrastructures [5,6]. Recent works in this field have demonstrated the possibility to conduct operations such as object grasping [7][8][9], valve turning [10], sensor installation and retrieval [2,11], contactbased inspection [3,12,13], insulation of cracks and leaks [14], or the realization of other tasks with grippers and other tools [15,16]. Several prototypes and morphologies of manipulators have been specifically developed for their integration in multi-rotors, including multi-joint arms [17,18], dual arm systems [7,10], linear actuators [11], delta manipulators [14], compliant joint arms [2,19,20], long reach aerial manipulators [2,21], or three-arm manipulators used for object grasping and as reconfigurable landing gear [22].…”