Voice user interface design



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What is Voice Interface Design?

Voice User Interface (VUI) means talking to your device (smartphone, smart speaker etc.) and instructing it to perform certain tasks – from switching on the lights to ordering plane tickets or sending money or getting detailed information. Our cross-functional team of professionals is ready to team up with your business to build a truly innovative voice-controlled product. Our specialized VUI team include usability experts, software engineers, AI experts, linguists, creatives, and copywriters. We use the most widely accepted voice assistants to create voice-controlled products like Siri (Apple), Cortana (Microsoft), Google Home (Google), and Alexa but we are able to enhance any digital product with custom built voice interfaces as well (e.g. based on Nuance technology).


What happens in a Voice Interface Design project?

When designing a voice-based user interface, we map the needs and habits of users. We explore what their intentions are in a given communication situation. Thus, when managing calendar entries, their intention might be time entry, time modification, and so on. In addition to gathering intentions, we observe when two users have a dialogue with each other (e.g., a director asks his assistant to schedule an appointment), how they talk, what words, phrases they use, what they often misunderstand, etc.

After preparing for the task, we compile a final list of intentions and build conversation patterns along each intent. We also use storyboards, text scenarios, and process maps to create schemas. This is very similar to creating chatbots, only in our case the communication takes place in verbal form and follows its peculiarities. Verbal communication is sometimes easier to support visually when users need to absorb complex information. In creating schemas, we use tools designed to design special voice-based interfaces, such as invocable.com, sayspring.com, dialogflow.com, etc.

Communication schemas can mostly be developed along simple decision trees, but in the case of more complex topics, their development takes place within the theoretical framework of constructive – analogical grammar with the involvement of artificial intelligence. We test the results of our work similarly to visual interfaces, but since the think aloud protocol cannot be used here, the testing of voice-based interfaces is performed by our specialized colleagues using the Wizard of Oz testing methodology.


Key Tools

  • Stakeholder Interviews. Meeting with your staff helps us define the business goals and use cases of your voice-controlled product.
  • Customer Interviews. When speaking with your customers, we pay special attention to their word choice and grammar as crucial input of the dialogue scripting.
  • Customer Personas. We hold workshops with your staff to define key customer types who will possibly interact with your voice-controlled product.
  • Brand Persona. Closely co-operating with key stakeholders of your business, we define the personality, the tone of voice, and the vocabulary of your product. You don’t want a sassy bank assistant, do you?
  • Functionality. We define what functions the customers will be able to use with the voice interface.
  • Dialogue Tree. With our dedicated software tools for voice design, we map every possible scenario of the human-computer interaction in the form of a complex tree model.
  • Detailed Wording. Our copywriters polish every detail of the scripted conversations.
  • Testing. Throughout the development process, the scripts can be validated regularly with the “Wizard of Oz” experiment.


Key Benefits

  • Accessible. VUI products can be operated by people with special needs, by children, by visually impaired or by the elderly.
  • Simple. Speech is the basic form of human communication. Operating a VUI product is almost instinctive.
  • Quick. Input via VUI is as quick as human speech.
  • Peripheral. Does not require eye contact or persistent focus.
  • Shared. Several users can access a VUI product at the same time.
  • Fun. This new way of interaction significantly enriches the experience of the users.


Your Involvement as a Client

Designing VUI products is an exciting and innovative field that requires special attention from your side as a client. Your involvement typically include:

  • Attending workshops
  • Contributing at all steps
  • Providing testers
  • Testing and validating results
  • Giving access to recorded conversations with users (e.g. call centre conversations)


Key Deliverables of a VUI Project

Deliverables in a VUI design project are typically not screens but a complex logic (processes , dialogues). Typical deliverables include:

  • Customer Personas
  • Brand Persona
  • Tone of Voice
  • Flow Charts
  • Dialogue Tree
  • Storyboards
  • Tex scenario
  • Phrase map
  • Information from client:Utilisation requirements of VUI, list of functions
  • Client cooperation:Attending workshops, Contributing at all steps, Providing testers, Testing and validating results, Giving access to recorded conversations with users (e.g. call centre conversations)
  • Deliverables:Customer Personas, Brand Persona, Tone of Voice, Flow charts, Dialogue tree, Storyboards, Text scenario, Phrase map