Combined passenger and goods transport using autonomous delivery robots in public transit offers promising solutions to urban mobility challenges. This paper examines the design, prototyping, and evaluation of interactive use cases for such a system developed within the regioKArgoTramTrain project. A key methodological contribution is our specially developed tram compartment simulation environment, which provides a controlled yet realistic setting for evaluating public transport interactions without the complexity of field tests. Through user studies with 21 participants, we investigated critical aspects of human-robot interaction including visual feedback mechanisms, intuitive controls, and operational indicators. Results showed that hands-on experience with the prototype significantly improved users’ perception, with acceptance rates increasing from 57.2% to 76.2%. However, security concerns became more pronounced after interaction, highlighting the need for clear communication of safety measures. Our findings demonstrate the technical feasibility of the combined transport concept and suggest directions for future research, including enhancements to the simulation environment and virtual reality-based evaluation approaches before field deployment.