Modelling and simulation of a load handling device for little load carriers with an integrated alignment mechanism

The subject of the thesis is the study of a device that allows the automation of the stacking process of load carriers or pallet cages using a pre-existing bridge crane. The load handling device is designed to be easily assembled and disassembled on the crane hook. Usage of a pre-existing bridge crane reduces the investment costs compared to building new automated stacking systems. The main goal of the thesis is to create virtual models of the load handling device concepts and simulate their dynamic performance. A prototype was built in previous works on this theme. The prototype uses a reaction wheel oriented on the vertical axis to control the yaw movement and a mobile counterweight to balance non-uniform loads. The device uses MEMS gyroscopes and a camera as position sensors to orient and align itself to the box. Experimental tests on the prototype have been carried out for the validation of mathematical equations and the estimation of the parameters. New features have been studied to increase the stability of the device and the positioning accuracy of the payload. These features are based on the use of reaction wheels, control moment gyroscopes and movable counterweights to move and balance the payload. A simplfied workflow has been designed to carry out picking, conveying and stacking operations.