Human factors and usability
We inform ideas and their implementation through a deep understanding of the relationship between people, products, and their environment.
We integrate human factors and usability throughout the design process across each of DCA's sectors, adopting domain-specific regulations and guidance. Emphasis is placed on moving beyond compliance to leverage the commercial benefits of more inclusive products and services that optimise system performance.
It's all about the context. The environment with in which products are used can have a marked impact on usage.
For example, the pressures of time and safety critical environments influence how tasks are completed. Wherever possible, we spend time exploring how intended users interact with products and services to ensure that they are fit for purpose and are helping to optimise system performance.
Measurement of system performance
Products and services rarely work in isolation. It is imperative they not only integrate effectively but they also contribute to the wider system performance.
Each system has its own measures of performance that typically include aspects such as, efficacy, efficiency, safety, resilience and usability. These values need to consider all stakeholders not just the end user (e.g. customers, supervisors, system owners, and maintenance staff). A numerical, evidence-based approach forms the basis of our approach to design. By providing quantifiable metrics from a comprehensive suite of tools and techniques, we are able to directly compare different concepts to legacy and competitor products.
The efficiency of a product or service can be examined by considering a detailed breakdown of the key tasks and operations.
A task model is created by describing the activity in detail. The overall task is divided in to sub tasks, which, in turn, are divided in to increasing levels of detail. By examining these models, it is possible to highlight which stages can be omitted or simplified. Time data can also be applied to each task step. Additional tools, such as critical path analysis, can be used to focus resources on the greatest efficiency savings.
A systematic approach to predicting where errors and mistakes can be made in current and future systems is imperative if low-frequency errors are to be identified.
A typical approach starts with a detailed task analysis model. We take each of the base level tasks and apply a set of standard keywords to each. The structured approach means that low frequency errors that are unlikely to be observed are identified. These threats can be summarised based on resulting hazardous situations (sometimes referred to as Top Events). Wherever possible, threats or errors will be designed out to prevent them happening. If this is not possible, clear feedback will be provided to communicate unsafe states to the user and allow them the opportunity to recover.
Postural and manual handling risk
The detailed design of a product can have a marked impact on the risk that it poses to its users in terms of manual handling and posture.
Careful control of a number of factors, such as the overall weight of the product, its distribution, frequency of operation, postures required to interact with the product and the type of grip, can dramatically reduce this risk. We use a number of validated tools to identify, prioritise and mitigate the operations that pose the greatest risk.
Anthropometric assessments and inclusive design
Inclusive design is good design as it considers all of its end users.
We use a number of anthropometric data sets that describe the size, weight and strength of different populations. Accordingly, we can estimate the number of potential users that will be accommodated for a given reach distance or actuation force. In many cases we validate these assumptions by recruiting participants to meet the target audience description (e.g. wheelchair users, visually-impaired users). We also use empathic modelling tools to investigate how different concepts can better support specific user needs.
Integrated iterative process
We integrate human factors in to each stage of the design process. Alongside input into the specification and evaluation, we evaluate design concepts at all levels of maturity.
CAD models and scale mannequins often form a foundation for the design. We like to create physical mock-ups of the products and services we are creating at the earliest opportunity. Early identification is critical in ensuring that insights can be integrated into the final design.
Wherever possible we spend time exploring how end users interact with products and services.
Particular attention is paid to departures from the instruction manual and the coping mechanisms that users adopt.
Desk-based analytical tools such as task analysis, error modelling, anthropometric and postural assessments form the foundation of many projects.
These are often supported by co-creation workshops to ensure stakeholder engagement. Stakeholders are given the opportunity to participate in the design process making physical adjustments to mock-up and prototypes to communicate preferred directions. A considered balance is taken between user-led and user-informed design throughout the design process.
We use a variety of prototyping techniques to capture insights throughout the design process. Rapid iteration plays a key role in arriving at the optimal design.
Appropriate use of technology
Where appropriate, we use the latest tools to explore user behaviour.
Tools such as eye tracking can reveal insights of which users are unaware or fail to verbalise.
Usability testing evaluates how safely, effectively and efficiently a product or system can be used by the target population.
Techniques can highlight key safety risks with products, as well as frustrations and negative experiences that can adversely affect user perceptions of a product or brand. Usability testing is typically conducted throughout the design process (formative testing) as well as at the end of the process (summative testing).
Instructions for use design
While an emphasis is always placed on developing intuitive products, invariably, some products will require structured documents with structured instructions for use.
There are a number of advantages to developing these instructions. By explicitly considering how the instructions will be written, the device can be modified to eliminate task steps and simplify task instructions. For example, the form of the product can be designed to allow it to be easier to describe and instruct. Likewise, the device can be developed to ensure that there is clear feedback for each step of the instruction.