Hybrid learning objects have great potential to increase the quality and attractiveness of vocational training. Due to the lack of substantiated findings on teaching and learning preferences for hybrid learning objects in vocational training, a user-centered development approach based on the principles of ISO 9241-210:2019 was pursued. ISO 9241-210:2019 defines principles of human-centered design, such as understanding and specifying the context-of-use, involving users throughout the design process, iterating solutions, and addressing the whole user experience. These principles guided the methodological approach of this study. Therefore, this approach aims to address the diversity of the target group early in the development process, systematically identify their needs and expectations, and integrate them into the design of a hybrid learning object on a technical topic. The hybrid learning object in the present context is a model of a heat pump, which is developed both as a physical training object and as a digital simulation for different vocations. This article presents the methodological approach and the results of the context-of-use analysis and requirements survey with trainers from an intercompany training provider. It also provides key insights into designing target group-specific hybrid learning opportunities. Through guided interviews and visual idea sketches, key didactic, technical, and content-related requirements were recorded from the trainers' perspective. The analysis of the interviews and visual idea sketches shows that trainers emphasized the need for intuitive interfaces and modular structures, so that individual functions of the heat pump can be explored step by step. They also requested adaptable levels of complexity to suit learners at different stages of their training, as well as technical compatibility with existing workshop and classroom infrastructures. In terms of didactics, the overarching goal is to enable error-tolerant learning. The requirements included providing realistic error scenarios, guided experimentation, and feedback mechanisms to support problem-solving skills. The resulting catalog of requirements, derived from the evaluation, forms the basis for the iterative development process of the learning object and ensures that trainer-specific requirements are considered. The results emphasize the desire for intuitive, modular, and adaptable content, as well as technical compatibility and customizable learning formats.

Keywords: Hybrid learning objects, user-centred design, vocational training, digital simulation.