Emergency Braking Control in 3D Overhead Cranes Using a Switching PD-Fuzzy Controller

Overhead cranes are used for lifting and transporting heavy loads in industries and construction sites. The loads are often suspended to the moving cart by cables, also referred as payload. When transporting, the suspended payload starts oscillating. The angle of oscillation is also referred as sway angle. Higher value of sway angle is dangerous from a safety point of view as well as life span of the machine parts and cables. Moreover, while moving, the payload may suddenly encounter an obstacle in its path and so emergency braking is extremely important to avoid collision. But sudden braking of the cart will increase the sway angle of the payload. Hence there is a need of an intelligent braking controller to stop the moving cart suddenly while keeping sway angles to the minimum. Considering these aspects of braking, a braking controller is designed using Fuzzy-PD controller for emergency braking in overhead cranes. Future work includes emergency braking control in drones carrying payloads, which fall in a similar class of systems as overhead cranes.