Adaptive system design for heterogeneous user groups in complex IT environments –
A usability assessment of TEDS, Rolls‑Royce’s Test Execution Data System
ABSTRACT
Complex systems must balance extensive functionality with intuitive and efficient user interaction. This challenge is particularly evident in systems that serve diverse user groups with varying levels of expertise, responsibilities and goals. This thesis investigates usability challenges within Rolls-Royce's Test Execution Data System (TEDS), a complex enterprise application that supports multiple user groups across different stages of the data lifecycle. Due to its flexible and process-agnostic design, TEDS enables diverse workflows but also creates significant usability challenges, especially for users with limited system knowledge.
Using a user-centred design approach, this study examines how users with different levels of expertise navigate the system, discover relevant functionality and develop mental models of interaction. Empirical findings reveal recurring usability issues, including information overload, limited discoverability and high cognitive load. The results highlight a fundamental tension between system flexibility and user guidance, demonstrating that many users struggle to retain knowledge of complex workflows and interaction structures over time.
Based on these findings, the thesis develops and evaluates a set of design concepts aimed at reducing perceived complexity and improving alignment between system structures and user tasks. The proposed concepts explore varying degrees of adaptivity, including manual customisation, role-based personalisation, context-sensitive assistance and AI-supported guidance mechanisms. The findings suggest that moderate forms of guidance and task-oriented interface design can improve usability without fundamentally compromising system flexibility.
The thesis contributes a structured analysis of usability challenges in complex enterprise systems and proposes a shift from a predominantly system-centric interface towards a more role- and task-oriented design perspective. The resulting concepts provide a foundation for future user-centred development of TEDS.