Key User Interface Design Principles
1. Clear Transaction Steps
The interface should present the parking payment process in a logical sequence.
A typical workflow includes parking identification, fee display, payment selection, transaction confirmation and receipt options.
2. Readable Touchscreen Content
Text size, contrast, button spacing and screen layout affect usability.
The interface should remain understandable under the expected lighting conditions.
3. Suitable Touch Target Size
Buttons should be large enough for reliable interaction, particularly in public self-service environments.
4. Multilingual Operation
The application can be designed to support multiple languages according to the destination market.
5. Clear Error Messages
Users should receive understandable instructions when a ticket cannot be read, payment fails or a printer is unavailable.
6. Consistent Navigation
Back, cancel and confirmation controls should remain predictable throughout the workflow.
Physical Accessibility Considerations
Operating Height
The touchscreen, card reader, scanner and ticket outlet should be positioned according to the intended users and applicable accessibility requirements.
Reach Distance
Users should be able to access required controls without excessive reaching.
Screen Viewing Angle
Display positioning should consider standing users, seated users and the installation environment.
Physical Access Space
Floor-standing kiosks require suitable surrounding space for approach and operation.
Alternative Interaction Methods
Depending on the project, accessibility options may include audio guidance, physical controls or other supported assistive features.
The required functions must be specified and validated against the applicable standards.
