Robotics and automated manufacturing

Abstract

Operator ergonomics is a crucial factor for well-being at work. In this paper, an intelligent overhead crane (hoist system) is presented to assist operators in handling large loads. Existing overhead cranes have several downsides when it comes to operator ergonomics and productivity. During operation, the equivalent inertia of the overhead crane is heavily affecting the flexibility of an operator to move a load. This can lead to potential muscles issues and to low productivity. Throughout this work, a design upgrade of an existing overhead crane that allows to improve both the flexibility of the system and ergonomic issues of operators, is described. With human operators being central in the load’s manipulation, it is not only important to consider the ergonomics but also the usability of these machines during the design stage. This includes assessment of where controls can be positioned, which forms of control, feedback and feed-forward are provided and how all of these affect efficiency and effectiveness of the solution in the specific context. After capturing the requirements of operators in different contexts, a prototype is built which includes several upgrades compared to existing systems. First, a semi-automatic movement system (“Follow-Me”) is implemented. This system reduces operator forces and increases handling speed for movement in the X-Y plane. Secondly, the usage of wireless controls is explored as well as (color-coded) labeling and led-indicators on the crane. Finally, an intelligent gripping system for large panels is designed and constructed. This gripping system is capable of adjusting its gripping points automatically to the most suited positions.