The integration of Industry 4.0 technologies must consider the place of the operator in the production. In this paper, we adopt a human-machine cooperation perspective for modelling operator 4.0 in industrial systems. Our approach is supported by Cognitive Work Analysis (CWA) method. We used three phases of the CWA: Work Domain Analysis (WDA), Control Task Analysis (ConTA), and Social Organization and Cooperation Analysis (SOCA), to model the functional and cognitive constraints as well as the function allocation. The paper especially uses two modeling tools-Abstraction Hierarchy and Decision Ladder-that could support the positioning and the design of Technology 4.0-based assistance systems. This model is applied to the specific activity of orders picking. This activity integrates both function of planning and organization of the different production lots and these functions can be shared between order picker 4.0 and specific Industry 4.0 technologies.