Experimental analysis for behavior and damage of batteries caused by collisions of structure and drones in horizontal flight

Abstract

This paper aims to clarify the behavior and damage conditions of batteries when multi-rotor unmanned aerial vehicles (drones) in horizontal flight collide with a structure to obtain the engineering knowledge that serves to consider the method of the safety performance evaluation of drone batteries in the collision. Drones with maximum takeoff weight of 15.5 kg, 24.5 kg, and 50 kg for aerial photographing, agricultural chemical spraying, and material transporting were used in the experiment analysis. The drones were ejected from an ejection system and collided with a barrier. The behavior of the drones and the batteries were captured on high-speed cameras. In addition, collision loads on the barrier and accelerations of the drones and their batteries were measured. The behavior of the drones and the batteries were considered based on the analysis results of the high-speed cameras. When the drones collided with the barrier, the batteries attached to the drones with snap-fit, rubber bands, and hook-and-loop fasteners separated from the drones. The separated batteries subsequently collided with the barrier. In the collision of the batteries and the barrier, the acceleration of the battery attached to the front of the drone by snap-fit was maximum. The acceleration was approximately 2.2 times larger than the acceleration given to the battery by the impact testing machine in the JIS standard (JIS C62133-2) that defines the test method for the safe operation of lithium secondary batteries used for portable devices. The damage conditions of batteries were presented and discussed from the viewpoint of the collision safety of batteries.

Keywords

• unmanned aerial vehicle
• drone
• uav battery
• collision
• experimental analysis
• behavior
• damaged condition
• safety performance evaluation