Morphological Intelligence in Dynamic Aerial Docking: A Bistable Tension-Hinge Gripper

Area of Science:

• Robotics
• Mechanical Engineering
• Aerospace Engineering

Background:

• Dynamic aerial docking is crucial for advanced unmanned aerial vehicle (UAV) applications but remains challenging.
• Conventional active grippers face limitations due to sensing delays, actuation latency, and impact vulnerability.

Purpose of the Study:

• To develop an aerial docking system that overcomes the limitations of conventional methods.
• To enable rapid, reliable, and autonomous aerial docking for UAVs through integrated mechanical design and flight control.

Main Methods:

• Introduction of the Bistable Tension-Hinge Gripper (BTHG) that uses morphological intelligence for passive locking.
• Integration of the BTHG with onboard perception and a PX4/ROS2 flight control framework for autonomous operation.
• Bench testing to evaluate locking transition time, holding force, and autonomous docking performance at various approach speeds.

Main Results:

• The BTHG achieves a rapid locking transition in 0.16 seconds using passive energy release.
• The gripper provides a maximum holding force of 54.8 N and absorbs collision shocks.
• A fully autonomous docking pipeline was demonstrated at approach speeds up to 1.4 m/s.

Conclusions:

• The BTHG system enables reliable dynamic aerial docking by shifting contact response from software to hardware design.
• This technology facilitates practical applications such as aerial logistics relay and UAV recovery.
• The passive locking mechanism enhances robustness and reduces the need for active feedback during docking.