Core Concepts
A haptic-based bilateral teleoperation strategy is proposed to compensate for human reaction time when an aerial manipulator extracts a wedged object from a static structure, which involves an abrupt decrease in interaction force.
Abstract
The paper presents a haptic-based bilateral teleoperation strategy for an aerial manipulator to extract a wedged object from a static structure, compensating for the limitations of human reaction time.
The key highlights are:
A haptic device with a 4-degree-of-freedom robotic arm and a gripper is fabricated to emulate the movement of the aerial manipulator during the wedged object extraction task.
The teleoperation strategy is divided into two phases:
Nominal flight phase: The aerial manipulator is teleoperated by the human operator using the haptic device.
Recovery flight phase: After the object extraction is detected, the aerial manipulator and the haptic device are controlled autonomously to avoid destabilization or excessive overshoot in the aerial manipulator's position.
An algorithm is developed to detect the extraction of the wedged object by monitoring the change in the external force exerted on the aerial manipulator.
Reference trajectory generation methods are designed for the aerial manipulator and the haptic device during the recovery flight phase to ensure a smooth transition and fast recovery to the initial position.
Comparative plug-pulling experiments are conducted with a quadrotor-based aerial manipulator, validating that the proposed teleoperation strategy reduces the overshoot in the aerial manipulator's position and ensures faster recovery after the object extraction compared to the baseline method.
Stats
The total mass of the UAM is 2.50 kg.
The maximum speeds of the UAM along the x, y, and z-axes of the body frame are 0.4 m/s, 0.4 m/s, and 0.4 m/s, respectively.
The maximum absolute values of the displacement of the haptic device's tooltip along the x, y, and z-axes are 0.2 m, 0.2 m, and 0.2 m, respectively.
The time duration of the recovery flight is 5.0 s.
Quotes
"To resolve these problems, the "human-in-the-loop" control of a UAM is adopted to utilize humans' decision-making ability while conducting complex tasks."
"When those situations occur, the instantaneous fully autonomous control of the UAM and the haptic device after the abrupt force change can prevent an excessive overshoot in the UAM's position or system destabilization induced by the operator's long reaction time."