The process of designing and verifying the usability of a product needs well-planned and organised actions. Human-centred design and usability engineering are thus severe action points also for the management of the product development team. To deal with complex communication environments, technologies and terminals there should be methods to cover full end-to-end interaction scenarios. This sometimes requires close co-operation of different parties (product design team, network operator and service provider).
The presented methods for usability planning and usability risk management provide a systematic way to analyse the project needs and to plan usability engineering activities through the project lifecycle. The methods are built by:
a) differentiating coordination and performance tasks
b) differentiating coordination tasks into project coordination and coordination of usability engineering.
c) differentiating coordination further into planning and follow-up tasks d) maintaining usability risk management data.
Usability Plan provides a method for synchronising usability engineering with other CE activities and coordination tasks. In general, a Usability Plan supports the project work effectively.
This study confirms the observation of Premkumar and King (1994) that a longer planning horizon enables better planning and performance. In this case the longer planning horizon is the product development lifecycle instead of a shorter timescale, such as a single usability test. The need for the top management's continued commitment during implementation of the plan is important, and according to my practical experiences in the case project, a fundamental necessity. It improves the Usability Plan for usability engineering Lifecycle (Mayhew 1999, Daly-Jones et al. 1999) by describing the planning tools in the framework of a CE project. The shortcoming of earlier descriptions is from the CE point of view, that they do not explicitly describe how the product design plans and states can be utilised for planning the usability efforts and how the project management can utilise information obtained from usability engineering for planning other project activities.
The finding of Blackburn et al. (1996) was that the concurrency is less prevalent between than inside design stages. We have shown (for example Table 7.2) that the usability engineering and the human-centred design activities can help in overcoming this discontinuation, especially in the turning point from the early design to the late design. Thus, concurrency of usability engineering is very much prevalent between stages and, unlike in software engineering, the concurrency of usability engineering increases while moving across software-hardware interface or across the stages.
The limitation of this approach is, that it requires early and continuous presence in the project to be efficient and effective, i.e. it encourages the project usability engineering instead of consulting-based or subcontracted usability engineering. There are two main lessons we have learned during this study:
- a project should have a Usability Plan as part of the project documentation in order to enable efficient and effective usability engineering.
- during the project usability engineering it is important to collect measurable data about performed actions, design improvements etc. in order to justify and better plan forthcoming usability engineering projects.
Is it possible to develop a method for planning usability work with CE? We have now shown that this is possible by adopting methods and practices used in other engineering areas and planning the actions according to CE process phases. However, the main consequence of concurrency for planning the usability work is related to organising the tasks. In a CE project the Usability Plan verifies that the project has capability to respond to the usability engineering needs of concurrent design activities.
The practitioners should strive for organising (coordinate and perform) usability engineering in the scope of the product development project instead of working in fire-fighting mode, using the same coordination tools as are used in other areas of the project coordination.
The goal of usability engineering is to ensure the quality of a system in terms of usability. The Usability Plan is a tool for enabling this. Further research is needed to define perceptual metrics for evaluating feasibility, accuracy and flexibility of a Usability Plan and usability risk management.
8 Managing Usability Engineering in Complex Concurrent Product Development
How can usability engineering be managed in highly complex innovative product development?
When usability engineering is performed in CE product development, there are stages where usability engineering needs to be refocused in order to perform successfully in the changing project environment. The focusing points follow the product development milestones but are not identical with those. From usability engineering perspective those points are critical for achieving effectiveness and efficiency in the product development.
The objective of this chapter is to find out what kinds of usability improvements are possible in different smart phone development phases and how product development stages actuate usability engineering. This research problem has been addressed in Keinonen et al. (1996). Our approach to usability engineering is holistic, i.e. it views the product usability as an entity that is built from the user interface, the external interface and the service interface (see Section 5.2.1).
Research reports describe the practical usability engineering problems in product development and solutions for those problems. The two basic problems are:
• usability engineering is done too late and
• lack of management support for usability engineering.
If the development organisation is not well adapted to human-centred design these problems are likely to appear. In addition to these problems, in fast paced CE it is simply difficult to usability engineer all needed parallel design and engineering areas. Concurrent product development is a complex engineering environment.
Current understanding and description of sequential product development phases does not give much support for serious usability engineering in a CE project. CE does not match with human- centred design. Hakiel (1997b) emphasises the need for product engineering across disciplines rather than software engineering. This raises a practical problem in concurrent product development: If the product is complex and resources limited, what usability activities should be performed and when?
Though the usability engineering lifecycle (Nielsen 1993, Mayhew 1999, ISO 13407) is well defined and known, it is often difficult to apply human-centred design in concurrent product development lifecycle due to the fast development pace, complexities and because the product development is not fundamentally based on human-centred approach. However, the more complex the product is technically or conceptually, the more important it is to involve elements from human-centred design (Keinonen et al. 1996).